ASDM Book 3 ASA 5515X 71 Vpn Config

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Cisco ASA Series VPN ASDM
Configuration Guide
Software Version 7.1
For the ASA 5505, ASA 5510, ASA 5520, ASA 5540, ASA 5550, ASA 5512-X,
ASA 5515-X, ASA 5525-X, ASA 5545-X, ASA 5555-X, ASA 5580, ASA 5585-X,
and the ASA Services Module
Released: December 3, 2012
Updated: March 31, 2014

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www.cisco.com
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Addresses, phone numbers, and fax numbers
are listed on the Cisco website at
www.cisco.com/go/offices.

Text Part Number: N/A, Online only

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Cisco ASA Series VPN ASDM Configuration Guide
Copyright © 2012-2014 Cisco Systems, Inc. All rights reserved.

CONTENTS
About This Guide

i

Document Objectives

i

Related Documentation
Conventions

i

ii

Obtaining Documentation and Submitting a Service Request

PART

Configuring Site-to-Site and Client VPN

1

CHAPTER

ii

2

VPN Wizards 2-1
VPN Overview

2-1

IPsec IKEv1 Remote Access Wizard 2-2
Remote Access Client 2-2
VPN Client Authentication Method and Tunnel Group Name
Client Authentication 2-3
User Accounts 2-4
Address Pool 2-4
Attributes Pushed to Client (Optional) 2-4
IKE Policy 2-5
IPsec Settings (Optional) 2-6
Summary 2-6
IPsec Site-to-Site VPN Wizard
Peer Device Identification
Traffic to Protects 2-7
Security 2-7
NAT Excempt 2-8
Summary 2-8

2-3

2-7
2-7

AnyConnect VPN Wizard 2-9
Connection Profile Identification 2-9
VPN Protocols 2-9
Client Images 2-10
Authentication Methods 2-10
Client Address Assignment 2-10
Network Name Resolution Servers 2-11
NAT Exempt 2-11

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AnyConnect Client Deployment
Summary 2-11

2-11

Clientless SSL VPN Wizard 2-11
SSL VPN Interface 2-12
User Authentication 2-12
Group Policy 2-12
Bookmark List 2-13
Summary 2-13

CHAPTER

3

Configuring IKE, Load Balancing, and NAC
Enabling IKE on an Interface

3-1

3-1

Setting IKE Parameters for Site-to-Site VPN
IKE Parmeters 3-2
NAT Transparency 3-2
Identity Sent to Peer 3-3
Session Control 3-3
IKE v2 Specific Settings 3-4

3-2

Creating IKE Policies 3-5
About IKE 3-5
Configuring IKE Policies 3-5
Adding an IKEv1 Policy 3-6
Adding an IKEv2 Policy 3-7
Assignment Policy 3-9
Configuring IPsec 3-9
Adding Crypto Maps 3-10
Creating an IPsec Rule/Tunnel Policy (Crypto Map) - Basic Tab 3-12
Creating IPsec Rule/Tunnel Policy (Crypto Map) - Advanced Tab 3-13
Creating IPsec Rule/Traffic Selection Tab 3-15
Pre-Fragmentation 3-17
Edit IPsec Pre-Fragmentation Policy 3-18
IPsec Transform Sets 3-18
Add/Edit IPsec Proposal (Transform Set) 3-19
Add/Edit IPsec Proposal 3-19
Configuring Load Balancing 3-20
Creating Virtual Clusters 3-20
Geographical Load Balancing 3-21
Comparing Load Balancing to Failover 3-22
Load Balancing Licensing Requirements 3-22
Eligible Clients 3-22
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Load Balancing Prerequisites 3-23
Certificate Verification 3-23
Configuring VPN Cluster Load Balancing with the High Availability and Scalability Wizard
Configuring Load Balancing (Without the Wizard) 3-25
Enable Clientless SSL VPN Load Balancing Using FQDNs 3-27
Setting Global NAC Parameters

3-23

3-27

Configuring Network Admission Control Policies 3-28
Add/Edit Posture Validation Exception 3-30

CHAPTER

4

General VPN Setup

4-1

AnyConnect Customization/Localization 4-1
AnyConnect Customization/Localization > Resources 4-2
AnyConnect Customization/Localization > Binary and Script 4-2
AnyConnect Customization/Localization > GUI Text and Messages 4-3
AnyConnect Customization/Localization > Customized Installer Transforms 4-4
AnyConnect Customization/Localization > Localized Installer Transforms 4-4
Client Software
4-4
Edit Client Update Entry
Default Tunnel Gateway

4-6

4-6

Group Policies 4-7
Configuring External Group Policies 4-8
Adding an LDAP or RADIUS Server to a Network (Client) Access External Group Policy 4-9
Configuring Network (Client) Access Internal Group Policies 4-9
Configuring General Attributes for an Internal Group Policy 4-9
Configuring Server Attributes for an Internal Group Policy 4-12
Configuring Split Tunneling for AnyConnect Traffic 4-13
Configuring VPN Policy Attributes for a Local User 4-16
Configuring a Browser Proxy for an Internal Group Policy 4-18
Configuring General AnyConnect Client Attributes for an Internal Group Policy 4-19
IPsec (IKEv1) Client 4-23
Configuring IPsec (IKEv1) Client Client Firewall Attributes for an Internal Group Policy 4-25
Configuring IPsec (IKEv1) Client Hardware Client Attributes for an Internal Group Policy 4-26
Configuring Clientless SSL VPN Internal Group Policies 4-29
Configuring Clientless SSL VPN General Attributes for an Internal Group Policy 4-29
Configuring the Clientless SSL VPN Access Portal for an Internal Group Policy 4-31
Configuring Portal Customization for a Clientless SSL VPN Internal Group Policy 4-33
Configuring Login Settings for a Clientless SSL VPN Internal Group Policy 4-33
Configuring Single Signon and Auto Signon Servers for a Clientless SSL VPN Access Internal
Group Policy 4-33
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Configuring Session Settings for Clientless SSL VPN Access
Configuring Site-to-Site Internal Group Policies 4-33
Defining Time Ranges 4-35
Add/Edit Time Range 4-35
Add/Edit Recurring Time Range 4-36
Access Control List Manager 4-36
Standard Access Control List 4-37
Extended Access Control List 4-37
Add/Edit/Paste ACE 4-38
Browse Source/Destination Address 4-40
Browse Source/Destination Port 4-40
Add TCP Service Group 4-40
Browse ICMP 4-41
Add ICMP Group 4-41
Browse Other 4-42
Add Protocol Group 4-42
Client Firewall with Local Printer and Tethered Device Support
Add/Edit Standard Access List Rule 4-47
Add/Edit Server and URL List 4-47
Add/Edit Server or URL 4-48
Configuring AnyConnect VPN Client Connections 4-48
Using AnyConnect Client Profiles 4-51
Importing an AnyConnect Client Profile 4-52
Exporting an AnyConnect Client Profile 4-52
Exempting AnyConnect Traffic from Network Address Translation

4-33

4-43

4-52

Configuring AnyConnect VPN Connections 4-57
Specifying a Device Certificate 4-58
Configuring Port Settings 4-59
Setting the Basic Attributes for an AnyConnect VPN Connection 4-59
Setting Advanced Attributes for a Connection Profile 4-61
Setting General Attributes for an AnyConnect SSL VPN Connection 4-61
Setting Client Addressing Attributes for an AnyConnect SSL VPN Connection 4-63
Configuring Authentication Attributes for a Connection Profile 4-63
Configuring Secondary Authentication Attributes for an SSL VPN Connection Profile
Configuring Authorization Attributes for an SSL VPN Connection Profile 4-66
Adding or Editing Content to a Script for Certificate Pre-Fill-Username 4-67
Configuring AnyConnect Secure Mobility 4-69
Add or Edit MUS Access Control 4-71
Configuring Clientless SSL VPN Connections
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4-71

4-64

Contents

Add or Edit Clientless SSL VPN Connections 4-72
Add or Edit Clientless SSL VPN Connections > Basic 4-72
Add or Edit Clientless SSL VPN Connections > Advanced 4-73
Add or Edit Clientless SSL VPN Connections > Advanced > General 4-73
Add or Edit Clientless or SSL VPN Client Connection Profile or IPsec Connection Profiles> Advanced
> Authentication 4-74
Assign Authentication Server Group to Interface 4-74
Add or Edit SSL VPN Connections > Advanced > Authorization
4-74
Assign Authorization Server Group to Interface 4-75
Add or Edit SSL VPN Connections > Advanced > SSL VPN 4-75
Add or Edit Clientless SSL VPN Connections > Advanced > Clientless SSL VPN 4-76
Add or Edit Clientless SSL VPN Connections > Advanced > NetBIOS Servers 4-77
Configure DNS Server Groups 4-78
Add or Edit Clientless SSL VPN Connections > Advanced > Clientless SSL VPN 4-78
IPsec Remote Access Connection Profiles

4-78

Add or Edit an IPsec Remote Access Connection Profile 4-79
Add or Edit IPsec Remote Access Connection Profile Basic

4-79

Mapping Certificates to IPsec or SSL VPN Connection Profiles 4-80
Site-to-Site Connection Profiles 4-84
Add/Edit Site-to-Site Connection
4-85
Adding or Editing a Site-to-Site Tunnel Group 4-86
Crypto Map Entry 4-88
Crypto Map Entry for Static Peer Address 4-89
Managing CA Certificates 4-90
Install Certificate 4-90
Configure Options for CA Certificate 4-90
Revocation Check Dialog Box 4-90
Add/Edit Remote Access Connections > Advanced > General 4-91
Configuring Client Addressing 4-92
Add/Edit Connection Profile > General > Authentication 4-95
Add/Edit SSL VPN Connection > General > Authorization 4-95
Add/Edit SSL VPN Connections > Advanced > Accounting 4-96
Add/Edit Tunnel Group > General > Client Address Assignment 4-97
Add/Edit Tunnel Group > General > Advanced 4-97
Add/Edit Tunnel Group > IPsec for Remote Access > IPsec 4-98
Add/Edit Tunnel Group for Site-to-Site VPN 4-99
Add/Edit Tunnel Group > PPP 4-100
Add/Edit Tunnel Group > IPsec for LAN to LAN Access > General > Basic
Add/Edit Tunnel Group > IPsec for LAN to LAN Access > IPsec 4-102

4-100

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Clientless SSL VPN Access > Connection Profiles > Add/Edit > General > Basic
Configuring Internal Group Policy IPsec Client Attributes 4-104
Configuring Client Addressing for SSL VPN Connections 4-106
Assign Address Pools to Interface 4-106
Select Address Pools 4-106
Add or Edit an IP Address Pool 4-107
Authenticating SSL VPN Connections 4-107
System Options

4-107

Zone Labs Integrity Server
Easy VPN Remote

4-108

4-109

Advanced Easy VPN Properties
AnyConnect Essentials
DTLS Settings

4-111

4-113

4-113

AnyConnect VPN Client Images 4-114
Add/Replace AnyConnect VPN Client Image
Upload Image 4-115
Bypass Interface ACL

4-114

4-115

Configuring AnyConnect Host Scan 4-115
Host Scan Dependencies and System Requirements 4-116
Dependencies 4-116
System Requirements 4-116
Licensing 4-116
Entering an Activation Key to Support Advanced Endpoint Assessment
Host Scan Packaging 4-117
Installing and Enabling Host Scan on the ASA 4-117
Installing or Upgrading Host Scan 4-118
Enabling or Disabling Host Scan 4-119
Enabling or Disabling CSD on the ASA 4-119
Viewing the Host Scan Version Enabled on the ASA 4-120
Uninstalling Host Scan 4-120
Uninstalling CSD from the ASA 4-120
Assigning AnyConnect Posture Module to a Group Policy 4-121
Other Important Documentation Addressing Host Scan 4-121
Configuring Maximum VPN Sessions

4-122

Configuring the Pool of Cryptographic Cores

CHAPTER

5

Configuring IP Addresses for VPNs

5-1

Configuring an IP Address Assignment Policy
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4-122

5-1

4-117

4-103

Contents

Configuring IP Address Assignment Options using ASDM 5-2
Viewing Address Assignment Methods 5-3
Viewing IPv4 and IPv6 Address Assignments using ASDM 5-3
Configuring Local IP Address Pools 5-3
Configuring Local IPv4 Address Pools Using ASDM
Configuring Local IPv6 Address Pools Using ASDM

5-3
5-4

Configuring DHCP Addressing 5-5
Assigning IP addresses using DHCP 5-5
Configure Your DHCP Servers 5-5
Assign the DHCP IP Addressing to a Group Policy

CHAPTER

6

Assigning IP Addresses to Local Users

5-6

Configuring Dynamic Access Policies

6-1

5-5

Information About Dynamic Access Policies 6-1
DAP and Endpoint Security 6-2
DAP Support for Remote Access Connection Types 6-2
Remote Access Connection Sequence with DAPs 6-2
Licensing Requirements for Dynamic Access Policies
Advanced Endpoint Assessment license 6-3
SSL VPN license (client) 6-3
AnyConnect Mobile License 6-3
Dynamic Access Policies Interface

6-4

Configuring Dynamic Access Policies
Testing Dynamic Access Policies

6-3

6-6

6-8

DAP and Authentication, Authorization, and Accounting Services
Configuring AAA Attributes in a DAP 6-9
Retrieving Active Directory Groups 6-11

6-9

Configuring Endpoint Attributes Used in DAPs 6-13
Adding an Anti-Spyware or Anti-Virus Endpoint Attribute to a DAP
Adding an Application Attribute to a DAP 6-15
Adding Mobile Posture Attributes to a DAP 6-16
Adding a File Endpoint Attribute to a DAP 6-17
Adding a Device Endpoint Attribute to a DAP 6-18
Adding a NAC Endpoint Attribute to a DAP 6-19
Adding an Operating System Endpoint Attribute to a DAP 6-20
Adding a Personal Firewall Endpoint Attribute to a DAP 6-20
Adding a Policy Endpoint Attribute to a DAP 6-21
Adding a Process Endpoint Attribute to a DAP 6-22

6-14

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Contents

Adding a Registry Endpoint Attribute to a DAP 6-23
DAP and AntiVirus, AntiSpyware, and Personal Firewall Programs
Endpoint Attribute Definitions 6-24
Configuring DAP Access and Authorization Policy Attributes
Performing a DAP Trace

6-31

Guide to Creating DAP Logical Expressions using LUA 6-31
Syntax for Creating Lua EVAL Expressions 6-32
The DAP CheckAndMsg Function 6-33
Additional Lua Functions 6-35
CheckAndMsg with Custom Function Example 6-38
Further Information on Lua 6-38
Operator for Endpoint Category 6-38
DAP Examples 6-38

CHAPTER

7

E-Mail Proxy

7-1

Configuring E-Mail Proxy

7-1

AAA 7-2
POP3S Tab 7-2
IMAP4S Tab 7-4
SMTPS Tab 7-5
Access 7-7
Edit E-Mail Proxy Access
Authentication

7-8

Default Servers
Delimiters

CHAPTER

8

7-8

7-10

7-11

Monitoring VPN

8-1

VPN Connection Graphs
IPsec Tunnels 8-1
Sessions 8-2

8-1

VPN Statistics 8-2
Sessions Window 8-2
Viewing Active AnyConnect Sessions
Viewing VPN Sessions Details 8-6
Cluster Loads 8-8
Crypto Statistics 8-9
Compression Statistics 8-9
Encryption Statistics 8-9

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8-5

6-27

6-24

Contents

Global IKE/IPsec Statistics 8-10
NAC Session Summary 8-10
Protocol Statistics 8-11
VLAN Mapping Sessions 8-11
SSO Statistics for Clientless SSL VPN Session 8-11
VPN Connection Status for the Easy VPN Client 8-13

CHAPTER

9

Configuring SSL Settings

9-1

SSL Settings 9-1
SSL 9-2

CHAPTER

10

Configuring an External Server for Authorization and Authentication

10-1

Understanding Policy Enforcement of Authorization Attributes 10-1
Defining the ASA LDAP Configuration 10-2
Guidelines 10-2
Active Directory/LDAP VPN Remote Access Authorization Examples 10-2
User-Based Attributes Policy Enforcement 10-3
Placing LDAP Users in a Specific Group Policy 10-5
Enforcing Static IP Address Assignment for AnyConnect Tunnels 10-7
Enforcing Dial-in Allow or Deny Access 10-9
Enforcing Logon Hours and Time-of-Day Rules 10-12
Example of Creating a Group Policy for a Local User 10-13

PART

Configuring a Clientless SSL VPN

2

CHAPTER

11

Introduction to Clientless SSL VPN

11-1

Introduction to Clientless SSL VPN 11-1
Prerequisites 11-2
Guidelines and Limitations 11-2

CHAPTER

12

Basic Clientless SSL VPN Configuration
Clientless SSL VPN Security Precautions
Configuring Clientless SSL VPN Access

12-1
12-1
12-2

Verifying Clientless SSL VPN Server Certificates
Java Code Signer

12-3

12-6

Configuring Browser Access to Plug-ins 12-7
Preparing the Security Appliance for a Plug-in 12-8
Installing Plug-ins Redistributed by Cisco 12-8

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Providing Access to a Citrix XenApp Server 12-10
Preparing the Citrix XenApp Server for Clientless SSL VPN Access
Creating and Installing the Citrix Plug-in 12-11
Configuring Port Forwarding 12-11
Information About Port Forwarding 12-12
Configuring DNS for Port Forwarding 12-13
Making Applications Eligible for Port Forwarding 12-16
Adding/Editing a Port Forwarding Entry 12-16
Assigning a Port Forwarding List 12-16
Enabling and Switching off Port Forwarding 12-17
Configuring File Access 12-17
CIFS File Access Requirement and Limitation
Adding Support for File Access 12-18
Ensuring Clock Accuracy for SharePoint Access

12-18

12-18

Virtual Desktop Infrastructure (VDI) 12-19
Citrix Mobile Support 12-19
Supported Mobile Devices 12-19
Limitations 12-19
About Citrix Mobile Receiver User Logon 12-20
Configuring the ASA to Proxy a Citrix Server 12-20
Configuring a VDI Server 12-20
Configuring a VDI Proxy Server 12-21
Assigning a VDI Server to a Group Policy 12-21
Configuring ACLs 12-22
Adding or Editing ACEs 12-23
Configuration Examples for ACLs for Clientless SSL VPN

12-24

Configuring Browser Access to Client-Server Plug-ins 12-24
About Installing Browser Plug-ins 12-24
RDP Plug-in ActiveX Debug Quick Reference 12-26
Preparing the Security Appliance for a Plug-in 12-26

CHAPTER

13

Advanced Clientless SSL VPN Configuration

13-1

Microsoft Kerberos Constrained Delegation Solution
Requirements 13-1

13-1

Understanding How KCD Works 13-2
Authentication Flow with KCD 13-2
Adding a Windows Service Account in Active Directory 13-4
Configuring DNS for KCD 13-4
Configuring the ASA to Join the Active Directory Domain 13-5
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12-10

Contents

Configuring the Use of External Proxy Servers

13-7

SSO Servers 13-8
Configuring SiteMinder and SAML Browser Post Profile 13-8
Adding the Cisco Authentication Scheme to SiteMinder 13-10
Adding or Editing SSO Servers 13-10
Configuring Kerberos Server Groups 13-11
Configuring Bookmarks to Access the Kerberos Authenticated Services
Configuring Application Profile Customization Framework
Restrictions 13-13
Managing APCF Profiles 13-13
Uploading APCF Packages 13-14
Managing APCF Packets 13-14
APCF Syntax 13-15
Configuring Session Settings
Encoding

13-13

13-18

13-19

Content Cache

13-20

Content Rewrite 13-21
Configuration Example for Content Rewrite Rules
Using Email over Clientless SSL VPN 13-23
Configuring Email Proxies 13-23
Configuring Web email: MS Outlook Web App

13-22

13-23

Configuring Bookmarks 13-23
Adding a Bookmark for a URL with a GET or Post Method 13-24
Adding a URL for a Predefined Application Template 13-26
Adding a Bookmark for an Auto Sign-On Application 13-27
Importing and Exporting a Bookmark List 13-28
Importing and Exporting GUI Customization Objects (Web Contents) 13-29
Adding and Editing Post Parameters 13-29
Configuration Example for Setting a Bookmark or URL Entry 13-31
Configuration Example for Configuring File Share (CIFS) URL Substitutions
Customizing External Ports 13-32

CHAPTER

14

13-13

Configuring Policy Groups

13-31

14-1

Configuring Smart Tunnel Access 14-1
Configuring Smart Tunnel Access 14-1
About Smart Tunnels 14-1
Why Smart Tunnels? 14-2
Configuring a Smart Tunnel (Lotus Example) 14-3
Simplifying Configuration of Which Applications to Tunnel

14-4

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Adding Applications to Be Eligible for Smart Tunnel Access
About Smart Tunnel Lists 14-7
Creating a Smart Tunnel Auto Sign-On Server List 14-8
Adding Servers to a Smart Tunnel Auto Sign-On Server List
Enabling and Switching Off Smart Tunnel Access 14-9
Configuring Smart Tunnel Log Off 14-10
When Its Parent Process Terminates 14-10
With a Notification Icon 14-10
Using Proxy Bypass 14-11
Configuring Portal Access Rules

CHAPTER

15

15-1

Requiring Usernames and Passwords

15-1

15-2

Configuring Remote Systems to Use Clientless SSL VPN Features
Capturing Clientless SSL VPN Data 15-7
Creating a Capture File 15-8
Using a Browser to Display Capture Data

CHAPTER

16

Managing Passwords 16-4
Adding the Cisco Authentication Scheme to SiteMinder
Configuring the SAML POST SSO Server 16-5
Configuring SSO with the HTTP Form Protocol 16-6
Gathering HTTP Form Data 16-7
Using Auto Sign-On 16-10
Requiring Usernames and Passwords

Cisco ASA Series VPN ASDM Configuration Guide

16-2

16-5

16-12

16-12

Configuring Remote Systems to Use Clientless SSL VPN Features
Starting Clientless SSL VPN 16-13
Using the Clientless SSL VPN Floating Toolbar 16-13
Browsing the Web 16-14
Browsing the Network (File Management) 16-14

xiv

15-2

15-8

Configuring Clientless SSL VPN Users 16-1
Overview 16-1
Defining the End User Interface 16-1
Viewing the Clientless SSL VPN Home Page 16-2
Viewing the Clientless SSL VPN Application Access Panel
Viewing the Floating Toolbar 16-3

Communicating Security Tips

14-8

14-11

Clientless SSL VPN Remote Users
Communicating Security Tips

14-5

16-12

Contents

Using the Remote File Explorer 16-15
Using Port Forwarding 16-16
Using email Via Port Forwarding 16-18
Using email Via Web Access 16-18
Using email Via email Proxy 16-18
Using Smart Tunnel 16-19

CHAPTER

17

Using Clientless SSL VPN with Mobile Devices
Using Clientless SSL VPN with Mobile Devices
Restrictions 17-1

CHAPTER

18

Customizing Clientless SSL VPN

17-1
17-1

18-1

Customizing the Clientless SSL VPN User Experience 18-1
Customizing the Logon Page with the Customization Editor 18-1
Replacing the Logon Page with your own Fully Customized Page 18-3
Creating the Custom Login Screen File 18-4
Importing the File and Images 18-5
Configuring the Security Appliance to use the Custom Login Screen
Clientless SSL VPN End User Setup 18-6
Defining the End User Interface 18-6
Viewing the Clientless SSL VPN Home Page 18-7
Viewing the Clientless SSL VPN Application Access Panel 18-7
Viewing the Floating Toolbar 18-7
Customizing Clientless SSL VPN Pages 18-8
Information About Customization 18-9
Exporting a Customization Template 18-9
Editing the Customization Template 18-9
Login Screen Advanced Customization 18-15
Modifying Your HTML File 18-17
Customizing the Portal Page 18-18
Configuring Custom Portal Timeout Alerts 18-19
Specifying a Custom Timeout Alert in a Customization Object File
Customizing the Logout Page 18-20
Customizing the External Portal Page 18-21
Adding Customization Object 18-21
Importing/Exporting Customization Object 18-22

18-5

18-19

Creating XML-Based Portal Customization Objects and URL Lists 18-22
Understanding the XML Customization File Structure 18-23
Configuration Example for Customization 18-26
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Using the Customization Template 18-29
The Customization Template 18-29
Help Customization 18-41
Customizing a Help File Provided by Cisco 18-42
Creating Help Files for Languages Not Provided by Cisco
Import/Export Application Help Content 18-44
Customizing a Help File Provided by Cisco 18-45
Creating Help Files for Languages Not Provided by Cisco
Customizing Bookmark Help 18-46
Customizing a Help File Provided By Cisco 18-47
Creating Help Files for Languages Not Provided by Cisco

18-43

18-46

18-48

Translating the Language of User Messages 18-48
Understanding Language Translation 18-48
Editing a Translation Table 18-49
Adding a Translation Table 18-50
Importing/Exporting Language Localization 18-50

CHAPTER

19

Clientless SSL VPN Troubleshooting

19-1

Closing Application Access to Prevent hosts File Errors

19-1

Recovering from Hosts File Errors When Using Application Access 19-1
Understanding the hosts File 19-2
Stopping Application Access Improperly 19-2
Reconfiguring a Host’s File Automatically Using Clientless SSL VPN
Reconfiguring hosts File Manually 19-3
Sending an Administrator’s Alert to Clientless SSL VPN Users

CHAPTER

20

Clientless SSL VPN Licensing
Licensing

20-1

INDEX

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20-1

19-4

19-2

About This Guide
This preface introduces Cisco ASA Series VPN ASDM Configuration Guide and includes the following
sections:
•

Document Objectives, page 1

•

Related Documentation, page 1

•

Conventions, page 2

•

Obtaining Documentation and Submitting a Service Request, page 2

Document Objectives
The purpose of this guide is to help you configure VPN on the ASA using ASDM. This guide does not
cover every feature, but describes only the most common configuration scenarios.
This guide applies to the Cisco ASA series. Throughout this guide, the term “ASA” applies generically
to supported models, unless specified otherwise.

Note

ASDM supports many ASA versions. The ASDM documentation and online help includes all of the
latest features supported by the ASA. If you are running an older version of ASA software, the
documentation might include features that are not supported in your version. Similarly, if a feature was
added into a maintenance release for an older major or minor version, then the ASDM documentation
includes the new feature even though that feature might not be available in all later ASA releases. Please
refer to the feature history table for each chapter to determine when features were added. For the
minimum supported version of ASDM for each ASA version, see Cisco ASA Series Compatibility.

Related Documentation
For more information, see Navigating the Cisco ASA Series Documentation at
http://www.cisco.com/go/asadocs.

Cisco ASA Series VPN ASDM Configuration Guide

1

Conventions
This document uses the following conventions:
Convention

Indication

bold font

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values are in italic font.

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vertical bars.

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vertical bars.

string

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the string will include the quotation marks.

courier

font

courier bold

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font

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font Arguments for which you supply values are in courier italic font.

< >

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indicates a comment line.

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Obtaining Documentation and Submitting a Service Request
For information on obtaining documentation, using the Cisco Bug Search Tool (BST), submitting a
service request, and gathering additional information, see What’s New in Cisco Product Documentation
at: http://www.cisco.com/c/en/us/td/docs/general/whatsnew/whatsnew.html.
Subscribe to What’s New in Cisco Product Documentation, which lists all new and revised
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Cisco ASA Series VPN ASDM Configuration Guide

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1

Configuring Site-to-Site and Client VPN

CH AP TE R

2

VPN Wizards
The ASA provides Secure Socket Layer (SSL) remote access connectivity from almost any
Internet-enabled location using only a Web browser and its native SSL encryption. Clientless,
browser-based VPN lets users establish a secure, remote-access VPN tunnel to the adaptive security
appliance using a web browser. After authentication, users access a portal page and can access specific,
supported internal resources. The network administrator provides access to resources by users on a group
basis. Users have no direct access to resources on the internal network.
The Cisco AnyConnect VPN client provides secure SSL connections to the ASA for remote users with
full VPN tunneling to corporate resources. Without a previously-installed client, remote users enter the
IP address in their browser of an interface configured to accept clientless VPN connections. The ASA
downloads the client that matches the operating system of the remote computer. After downloading, the
client installs and configures itself, establishes a secure connection and either remains or uninstalls itself
(depending on the ASA configuration) when the connection terminates. In the case of a previously
installed client, when the user authenticates, the ASA examines the revision of the client and upgrades
the client as necessary.
With the addition of IKEv2 support in release 8.4, the end user can have the same experience
independent of the tunneling protocol used by the AnyConnect client session. This addition allows other
vendors’ VPN clients to connect to the ASAs. This support enhances security and complies with the
IPsec remote access requirements defined in federal and public sector mandates.
The VPN wizard lets you configure basic LAN-to-LAN and remote access VPN connections and assign
either preshared keys or digital certificates for authentication. Use ASDM to edit and configure advanced
features.

VPN Overview
The ASA creates a Virtual Private Network by creating a secure connection across a TCP/IP network
(such as the Internet) that users see as a private connection. It can create single-user-to-LAN connections
and LAN-to-LAN connections.
For LAN-to-LAN connections using both IPv4 and IPv6 addressing, the security appliance supports
VPN tunnels if both peers are Cisco ASA 5500 series security appliances, and if both inside networks
have matching addressing schemes (both IPv4 or both IPv6). This is also true if both peer inside
networks are IPv6 and the outside network is IPv6.
The secure connection is called a tunnel, and the ASA uses tunneling protocols to negotiate security
parameters, create and manage tunnels, encapsulate packets, transmit or receive them through the tunnel,
and unencapsulate them. The ASA functions as a bidirectional tunnel endpoint: it can receive plain

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IPsec IKEv1 Remote Access Wizard

packets, encapsulate them, and send them to the other end of the tunnel where they are unencapsulated
and sent to their final destination. It can also receive encapsulated packets, unencapsulate them, and send
them to their final destination.
The four VPN wizards described in this section are as follows:
•

IPsec IKEv1 Remote Access Wizard

•

IPsec Site-to-Site VPN Wizard

•

AnyConnect VPN Wizard

•

Clientless SSL VPN Wizard

IPsec IKEv1 Remote Access Wizard
Use the IKEv1 Remote Access Wizard to configuresecure remote access for VPN clients, such as mobile
users, and to identify the interface that connects to the remote IPsec peer.
Fields
•

VPN Tunnel Interface—Choose the interface that establishes a secure tunnel with the remote IPsec
peer. If the ASA has multiple interfaces, you need to plan the VPN configuration before running this
wizard, identifying the interface to use for each remote IPsec peer with which you plan to establish
a secure connection.

•

Enable inbound IPsec sessions to bypass interface access lists—Enable IPsec authenticated inbound
sessions to always be permitted through the security appliance (that is, without a check of the
interface access-list statements). Be aware that the inbound sessions bypass only the interface ACLs.
Configured group-policy, user, and downloaded ACLs still apply.

Remote Access Client
Remote access users of various types can open VPN tunnels to this ASA. Choose the type of VPN client
for this tunnel.
Fields
•

VPN Client Type
– Cisco VPN Client, Release 3.x or higher, or an Easy VPN Remote product.
– Microsoft Windows client using L2TP over IPsec—Specify the PPP authentication protocol.

The choices are PAP, CHAP, MS-CHAP-V1, MS-CHAP-V2, and EAP-PROXY:
PAP—Passes cleartext username and password during authentication and is not secure.
CHAP—In response to the server challenge, the client returns the encrypted [challenge plus
password] with a cleartext username. This protocol is more secure than the PAP, but it does not
encrypt data.
MS-CHAP, Version 1—Similar to CHAP but more secure in that the server stores and compares
only encrypted passwords rather than cleartext passwords as in CHAP.
MS-CHAP, Version 2—Contains security enhancements over MS-CHAP, Version 1.
EAP-Proxy—Enables EAP which permits the ASA to proxy the PPP authentication process to
an external RADIUS authentication server.
If a protocol is not specified on the remote client, do no specify it.

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IPsec IKEv1 Remote Access Wizard

– Specify if the client will send tunnel group name as username@tunnelgroup.

VPN Client Authentication Method and Tunnel Group Name
Use the VPN Client Authentication Method and Name pane to configure an authentication method and
create a connection policy (tunnel group).
Fields
•

Authentication Method—The remote site peer authenticates either with a preshared key or a
certificate.
– Pre-shared Key—Click to use a preshared key for authentication between the local ASA and the

remote IPsec peer.
Using a preshared key is a quick and easy way to set up communication with a limited number
of remote peers and a stable network. It may cause scalability problems in a large network
because each IPsec peer requires configuration information for each peer with which it
establishes secure connections.
Each pair of IPsec peers must exchange preshared keys to establish secure tunnels. Use a secure
method to exchange the preshared key with the administrator of the remote site.
– Pre-shared Key—Type an alphanumeric string between 1 and 128 characters.
– Certificate—Click to use certificates for authentication between the local ASA and the remote

IPsec peer. To complete this section, you must have previously enrolled with a CA and
downloaded one or more certificates to the ASA.
You can efficiently manage the security keys used to establish an IPsec tunnel with digital
certificates. A digital certificate contains information that identifies a user or device, such as a
name, serial number, company, department or IP address. A digital certificate also contains a
copy of the public key.
To use digital certificates, each peer enrolls with a certification authority (CA), which is
responsible for issuing digital certificates. A CA can be a trusted vendor or a private CA that
you establish within an organization.
When two peers want to communicate, they exchange certificates and digitally sign data to
authenticate each other. When you add a new peer to the network, it enrolls with a CA, and none
of the other peers require additional configuration.
Certificate Signing Algorithm—Displays the algorithm for signing digital certificates, rsa-sig
for RSA.
– Challenge/response authentication (CRACK)—Provides strong mutual authentication when the

client authenticates using a popular method such as RADIUS and the server uses public key
authentication. The security appliance supports CRACK as an IKE option in order to
authenticate the Nokia VPN Client on Nokia 92xx Communicator Series devices.
•

Tunnel Group Name—Type a name to create the record that contains tunnel connection policies for
this IPsec connection. A connection policy can specify authentication, authorization, and accounting
servers, a default group policy, and IKE attributes. A connection policy that you configure with this
VPN wizard specifies an authentication method and uses the ASA Default Group Policy.

Client Authentication
Use the Client Authentication pane to select the method by which the ASA authenticates remote users.

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IPsec IKEv1 Remote Access Wizard

Fields

Select one of the following options:
•

Authenticate using the local user database—Click to use authentication internal to the ASA. Use this
method for environments with a small, stable number of users. The next pane lets you create
accounts on the ASA for individual users.

•

Authenticate using an AAA server group—Click to use an external server group for remote user
authentication.
– AAA Server Group Name—Choose a AAA server group configured previously.
– New...—Click to configure a new AAA server group.

User Accounts
Use the User Accounts pane to add new users to the ASA internal user database for authentication
purposes.
Fields
•

Use the fields in this section to add a user.
– Username—Enter the username.
– Password—(Optional) Enter a password.
– Confirm Password—(Optional) Reenter the password.

•

Add—Click to add a user to the database after you have entered the username and optional
password.

•

Delete—To remove a user from the database, highlight the appropriate username and click Delete.

Address Pool
Use the Address Pool pane to configure a pool of local IP addresses that the ASA assigns to remote VPN
clients.
Fields
•

Tunnel Group Name—Displays the name of the connection profile (tunnel group) to which this
address pool applies. You set this name in the VPN Client and Authentication Method pane (step 3).

•

Pool Name—Select a descriptive identifier for the address pool.

•

New...—Click to configure a new address pool.

•

Range Start Address—Type the starting IP address in the address pool.

•

Range End Address—Type the ending IP address in the address pool.

•

Subnet Mask—(Optional) Choose the subnet mask for these IP addresses.

Attributes Pushed to Client (Optional)
Use the Attributes Pushed to Client (Optional) pane to have the ASA pass information about DNS and
WINS servers and the default domain name to remote access clients.

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IPsec IKEv1 Remote Access Wizard

Fields
•

Tunnel Group—Displays the name of the connection policy to which the address pool applies. You
set this name in the VPN Client Name and Authentication Method pane.

•

Primary DNS Server—Type the IP address of the primary DNS server.

•

Secondary DNS Server—Type the IP address of the secondary DNS server.

•

Primary WINS Server—Type the IP address of the primary WINS server.

•

Secondary WINS Server— Type the IP address of the secondary WINS server.

•

Default Domain Name—Type the default domain name.

IKE Policy
IKE, also called Internet Security Association and Key Management Protocol (ISAKMP), is the
negotiation protocol that lets two hosts agree on how to build an IPsec Security Association. Each IKE
negotiation is divided into two sections called Phase1 and Phase 2.
•

Phase 1 creates the first tunnel, which protects later IKE negotiation messages.

•

Phase 2 creates the tunnel that protects data.

Use the IKE Policy pane to set the terms of the Phase 1 IKE negotiations, which include the following:
•

An encryption method to protect the data and ensure privacy.

•

An authentication method to ensure the identity of the peers.

•

A Diffie-Hellman group to establish the strength of the of the encryption-key-determination
algorithm. The ASA uses this algorithm to derive the encryption and hash keys.

Fields
•

Encryption—Select the symmetric encryption algorithm the ASA uses to establish the Phase 1 SA
that protects Phase 2 negotiations. The ASA supports the following encryption algorithms:

Algorithm

Explanation

DES

Data Encryption Standard. Uses a 56-bit key.

3DES

Triple DES. Performs encryption three times using a 56-bit key.

AES-128

Advanced Encryption Standard. Uses a 128-bit key.

AES-192

AES using a 192-bit key.

AES-256

AES using a 256-bit key.

The default, 3DES, is more secure than DES but requires more processing for encryption and
decryption. Similarly, the AES options provide increased security but also require increased
processing.
•

Authentication—Choose the hash algorithm used for authentication and ensuring data integrity. The
default is SHA. MD5 has a smaller digest and is considered to be slightly faster than SHA. There
has been a demonstrated successful (but extremely difficult) attack against MD5. However, the
Keyed-Hash Message Authentication Code (HMAC) version used by the ASA prevents this attack.

•

Diffie-Hellman Group—Choose the Diffie-Hellman group identifier, which the two IPsec peers use
to derive a shared secret without transmitting it to each other. The default, Group 2 (1024-bit
Diffie-Hellman), requires less CPU time to execute but is less secure than Group 5 (1536-bit).

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IPsec IKEv1 Remote Access Wizard

Note

The default value for the VPN 3000 Series Concentrator is MD5. A connection between the ASA and
the VPN Concentrator requires that the authentication method for Phase I and II IKE negotiations be the
same on both sides of the connection.

IPsec Settings (Optional)
Use the IPsec Settings (Optional) pane to identify local hosts/networks which do not require address
translation. By default, the ASA hides the real IP addresses of internal hosts and networks from outside
hosts by using dynamic or static Network Address Translation (NAT). NAT minimizes risks of attack by
untrusted outside hosts but may be improper for those who have been authenticated and protected by
VPN.
For example, an inside host using dynamic NAT has its IP address translated by matching it to a
randomly selected address from a pool. Only the translated address is visible to the outside. Remote VPN
clients that attempt to reach these hosts by sending data to their real IP addresses cannot connect to these
hosts, unless you configure a NAT exemption rule.

Note

If you want all hosts and networks to be exempt from NAT, configure nothing on this pane. If you have
even one entry, all other hosts and networks are subject to NAT.
Fields
•

Interface—Choose the name of the interface that connects to the hosts or networks you have
selected.

•

Exempt Networks—Select the IP address of the host or network that you want to exempt from the
chosen interface network.

•

Enable split tunneling—Select to have traffic from remote access clients destined for the public
Internet sent unencrypted. Split tunneling causes traffic for protected networks to be encrypted,
while traffic to unprotected networks is unencrypted. When you enable split tunneling, the ASA
pushes a list of IP addresses to the remote VPN client after authentication. The remote VPN client
encrypts traffic to the IP addresses that are behind the ASA. All other traffic travels unencrypted
directly to the Internet without involving the ASA.

•

Enable Perfect Forwarding Secrecy (PFS)—Specify whether to use Perfect Forward Secrecy, and the
size of the numbers to use, in generating Phase 2 IPsec keys. PFS is a cryptographic concept where each
new key is unrelated to any previous key. In IPsec negotiations, Phase 2 keys are based on Phase 1 keys
unless PFS is enabled. PFS uses Diffie-Hellman techniques to generate the keys.
PFS ensures that a session key derived from a set of long-term public and private keys is not
compromised if one of the private keys is compromised in the future.
PFS must be enabled on both sides of the connection.
– Diffie-Hellman Group—Select the Diffie-Hellman group identifier, which the two IPsec peers

use to derive a shared secret without transmitting it to each other. The default, Group 2 (1024-bit
Diffie-Hellman), requires less CPU time to execute but is less secure than Group 5 (1536-bit).

Summary
The Summary pane displays all of the attributes of this VPN LAN-to-LAN connection as configured.

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IPsec Site-to-Site VPN Wizard

Fields

Back—To make changes, click Back until you reach the appropriate pane.
Finish—When you are satisfied with the configuration, click Finish. ASDM saves the LAN-to-LAN
configuration. After you click Finish, you can no longer use the VPN wizard to make changes to this
configuration. Use ASDM to edit and configure advanced features.
Cancel—To remove the configuration, click Cancel.

IPsec Site-to-Site VPN Wizard
Use this wizard to set up new site-to-site VPN tunnels. A tunnel between two devices is called a
site-to-site tunnel and is bidirectional. A site-to-site VPN tunnel protects the data using the IPsec
protocol.

Peer Device Identification
Identify the peer VPN device by its IP address and the interface used to access the peer.
Fields
•

Peer IP Address—Configure the IP address of the other site (peer device).

•

VPN Access Interface—Select the interface to use for the site-to-site tunnel.

•

IKEv2

Traffic to Protects
This step lets you identify the local network and remote network These networks protect the traffic using
IPsec encryption.
Fields
•

Local Networks—Identify the host used in the IPsec tunnel.

•

Remote Networks—Identify the networks used in the IPsec tunnel.

Security
This step lets you configure the methods to authenticate with the peer device. You can either choose the
simple configuration, and supply a pre-shared key. Or you can select Customized Configuration for more
advanced options, which are described below.
Authentication Tab

IKE version 1
•

Pre-shared Key—Using a preshared key is a quick and easy way to set up communication with a
limited number of remote peers and a stable network. It may cause scalability problems in a large
network because each IPsec peer requires configuration information for each peer with which it
establishes secure connections.

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IPsec Site-to-Site VPN Wizard

Each pair of IPsec peers must exchange preshared keys to establish secure tunnels. Use a secure
method to exchange the preshared key with the administrator of the remote site.
•

Device Certificate—Click to use certificates for authentication between the local ASA and the
remote IPsec peer.
You can efficiently manage the security keys used to establish an IPsec tunnel with digital
certificates. A digital certificate contains information that identifies a user or device, such as a name,
serial number, company, department or IP address. A digital certificate also contains a copy of the
public key.
When two peers want to communicate, they exchange certificates and digitally sign data to
authenticate each other. When you add a new peer to the network, it enrolls with a CA, and none of
the other peers require additional configuration.

IKE version 2
•

Local Pre-shared Key—Specify IPsec IKEv2 authentication methods and encryption algorithms.

•

Local Device Certificate—Authenticates VPN access through the security appliance.

•

Remote Peer Pre-shared Key—Click to use a preshared key for authentication between the local
ASA and the remote IPsec peer.

•

Remote Peer Certificate Authentication—When checked, the peer device is allowed to use the
certificate to authenticate itself to this device.

Encryption Algorithm

This tab lets you select the types of encryption algorithms used to protect the data.
IKE version 1
•

IKE Policy—Specify IKEv1 authentication methods.

•

IPsec Proposal—Specify IPsec encryption algorithms.

IKE version 2
•

IKE Policy—Specify IKEv2 authentication methods.

•

IPsec Proposal—Specify IPsec encryption algorithms.

NAT Excempt
Fields
•

Exempt ASA side host/network from address translation—Use the drop-down to choose a host or
network to be excluded from address translation.

Summary
Provides a summary of your selections from the previous wizard windows. The supported VPN protocols
are included in the summary as well as the IKE version chosen on the VPN Connection Type window.

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VPN Wizards
AnyConnect VPN Wizard

AnyConnect VPN Wizard
Use this wizard to configure ASA to accept VPN connections from the AnyConnect VPN client. This
wizard configures either IPsec (IKEv2) or SSL VPN protocols for full network access. The ASA
automatically uploads the AnyConnect VPN client to the end user’s device when a VPN connection is
established.
Warn the user that running the wizard does not mean the IKEv2 profile automatically applies in
predeployment scenarios. Either provide a pointer or the steps necessary to successfully predeploy
IKEv2.

Connection Profile Identification
The connection profile identification is used to identify the ASA to the remote acess users.
Fields
•

Connection Profile Name—Provide a name that the remote access users will access for VPN
connections.

•

VPN Access Interface—Choose an interface that the remote access users will access for VPN
connections.

VPN Protocols
Specify the VPN protocol allowed for this connection profile.
The AnyConnect client defaults to SSL. If you enable IPsec as a VPN tunnel protocol for the connection
profile, you must also create and deploy a client profile with IPsec enabled using the profile editor from
ASDM, and deploy the profile.
If you predeploy instead of weblaunch the AnyConnect client, the first client connection uses SSL, and
receives the client profile from the ASA during the session. For subsequent connections, the client uses
the protocol specified in the profile, either SSL or IPsec. If you predeploy the profile with IPsec specified
with the client, the first client connection uses IPsec. For more information about predeploying a client
profile with IPsec enabled, see the AnyConnect Secure Mobility Client Administrator Guide.
Fields
•

SSL

•

IPsec (IKE v2)

•

Device Certificate—Identifies the ASA to the remote access clients.

Note

•

Some AnyConnect features (such as always on, IPsec/IKEv2) require a valid device
certificate on the ASA.

Manage—Choosing Manage opens the Manage Identity Certificates window.
– Add—Choose Add to add an identity certificate and its details.
– Show Details—If you choose a particular certificate and click Show Details, the Certificate

Details window appears and provides who the certificate was issued to and issued by, as well as
specifics about its serial number, usage, associated trustpoints, valid timeframe, and so on.

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AnyConnect VPN Wizard

– Delete—Highlight the certificate you want to remove and click Delete.
– Export—Highlight the certificate and click Export to export the certificate to a file with or

without an encryption passphrase.
– Enroll ASA SSL VPN with Entrust—Gets your Cisco ASA SSL VPN appliance up and running

quickly with an SSL Advantage digitial certificate from Entrust.

Client Images
ASA can automatically upload the latest AnyConnect package to the client device when it accesses the
enterprise network. You can use a regular expression to match the user agent of a browser to an image.
You can also minimize connection setup time by moving the most commonly encountered operation
system to the top of the list.
Fields
•

Add

•

Replace

•

Delete

Authentication Methods
Specify authentication information on this screen.
Fields
•

AAA server group—Enable to let the ASA contact a remote AAA server group to authenticate the
user. Select a AAA server group from the list of pre-configured groups or click New to create a new
group.

•

Local User Database Details—Add new users to the local database stored on the ASA.
– Username—Create a username for the user.
– Password—Create a password for the user.
– Confirm Password—Re-type the same password to confirm.
– Add/Delete—Add or delete the user from the local database.

Client Address Assignment
Provide a range of IP addresses to remote SSL VPN users.
Fields
•

IPv4 Address Pools—SSL VPN clients receive new IP addresses when they connect to the ASA.
Clientless connections do not require new IP addresses. Address Pools define a range of addresses
that remote clients can receive. Select an existing IP Address Pool or click New to create a new pool.
If you select New, you will have to provide a starting and ending IP address and subnet mask.

•

IPv6 Address Pool—Select an existing IP Address Pool or click New to create a new pool.

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Clientless SSL VPN Wizard

Note

IPv6 address pools can not be created for IKEv2 connection profiles.

Network Name Resolution Servers
This step lets you specify which domain names are resolved for the remote user when accessing the
internal network.
Fields
•

DNS Servers—Enter the IP address of the DNS server.

•

WINS Servers—Enter the IP address of the WINS server.

•

Domain Name—Type the default domain name.

NAT Exempt
If network translation is enabled on the ASA, the VPN traffic must be exempt from this translation.
Fields
•

Exempt VPN traffic from network address translation

AnyConnect Client Deployment
You can install the AnyConnect client program to a client device with one of the following two methods:
•

Web launch—Installs automatically when accessing the ASA using a web browser.

•

Pre-deployment—Manually installs the AnyConnect client package.

Fields
•

Allow Web Launch—A global setting that affects all connections. If it is unchecked (disallowed),
AnyConnect SSL connections and clientless SSL connections do not work.

For pre-deployment, the disk0:/test2_client_profile.xml profile bundle contains an .msi file, and you
must include this client profile from the ASA in your AnyConnect package to ensure IPsec connection
functions as expected.

Summary
Provides a summary of your selections from the previous wizard windows. The supported VPN protocols
are part of the summary as well as the IKE version chosen.

Clientless SSL VPN Wizard
This wizard enables clientless, browser-based connections for specific, supported internal resources
through a portal page.

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Clientless SSL VPN Wizard

SSL VPN Interface
Provide a connection profile and the interface that SSL VPN users connect to.
Fields
•

Connection Profile Name

•

SSL VPN Interface—The interface users access for SSL VPN connections.

•

Digital Certificate—Specifies what the security appliance sends to the remote web browser to
authenticate the ASA.
– Certificate—Choose from the drop-down menu.

•

Accessing the Connection Profile
– Connection Group Alias/URL—The group alias is chosen during login from the Group

drop-down list. This URL is entered into the web browser.
– Display Group Alias list at the login page

User Authentication
Specify authentication information on this screen.
Fields
•

Authenticate using a AAA server group—Enable to let the ASA contact a remote AAA server group
to authenticate the user.
– AAA Server Group Name—Select a AAA server group from the list of pre-configured groups

or click New to create a new group.
•

Authenticate using the local user database—Add new users to the local database stored on the ASA.
– Username—Create a username for the user.
– Password—Create a password for the user.
– Confirm Password—Re-type the same password to confirm.
– Add/Delete—Add or delete the user from the local database.

Group Policy
Group policies configure common attributes for groups of users. Create a new group policy or select an
existing one to modify.
Fields
•

Create new group policy—Enables you to create a new group policy. Provide a name for the new
policy.

•

Modify existing group policy—Select an existing group policy to modify.

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Clientless SSL VPN Wizard

Bookmark List
Configure a list of group intranet websites that appear in the portal page as links. Some examples include
https://intranet.acme.com, rdp://10.120.1.2, vnc://100.1.1.1 and so on.
Fields
•

Bookmark List

•

Manage

Summary
Provides a summary of your selections from the previous wizard windows.

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Clientless SSL VPN Wizard

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3

Configuring IKE, Load Balancing, and NAC
IKE, also called ISAKMP, is the negotiation protocol that lets two hosts agree on how to build an IPsec
security association. To configure the ASA for virtual private networks, you set global IKE parameters
that apply system wide, and you also create IKE policies that the peers negotiate to establish a VPN
connection.
Load balancing distributes VPN traffic among two or more ASAs in a VPN cluster.
Network Access Control (NAC) protects the enterprise network from intrusion and infection from
worms, viruses, and rogue applications by performing endpoint compliance and vulnerability checks as
a condition for production access to the network. We refer to these checks as posture validation.
This chapter describes how to configure IKE, load balancing, and NAC. It includes the following
sections:
•

Enabling IKE on an Interface, page 3-1

•

Setting IKE Parameters for Site-to-Site VPN, page 3-2

•

Creating IKE Policies, page 3-5

•

Configuring IPsec, page 3-9

•

Configuring Load Balancing, page 3-20

•

Setting Global NAC Parameters, page 3-27

•

Configuring Network Admission Control Policies, page 3-28

Enabling IKE on an Interface
To use IKE, you must enable it on each interface you plan to use it on.
For VPN connections
Step 1

In ASDM, navigate to Configuration > Remote Access VPN > Network (Client) Access > AnyConnect
Connection Profiles

Step 2

In the Access Interfaces section, check Allow Access under IPsec (IKEv2) Access for the interfaces you
will use IKE on.

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For Site-to-Site VPN
Step 1

In ASDM, navigate to Configuration > Site-to-Site VPN > Connection Profiles

Step 2

Select the interfaces you want to use IKEv1 and IKEv2 on.

Setting IKE Parameters for Site-to-Site VPN
IKE Parmeters
In ASDM, navigate to Configuration > Site-to-Site VPN > Advanced > IKE Parameters

NAT Transparency
Enable IPsec over NAT-T

IPsec over NAT-T lets IPsec peers establish both remote access and LAN-to-LAN connections through
a NAT device. It does this by encapsulating IPsec traffic in UDP datagrams, using port 4500, thereby
providing NAT devices with port information. NAT-T auto-detects any NAT devices, and only
encapsulates IPsec traffic when necessary. This feature is enabled by default.
•

The ASA can simultaneously support standard IPsec, IPsec over TCP, NAT-T, and IPsec over UDP,
depending on the client with which it is exchanging data.

•

When both NAT-T and IPsec over UDP are enabled, NAT-T takes precedence.

•

When enabled, IPsec over TCP takes precedence over all other connection methods.

The ASA implementation of NAT-T supports IPsec peers behind a single NAT/PAT device as follows:
•

One LAN-to-LAN connection.

•

Either a LAN-to-LAN connection or multiple remote access clients, but not a mixture of both.

To use NAT-T you must:
•

Create an ACL for the interface you will be using to open port 4500 (Configuration > Firewall >
Access Rules).

•

Enable IPsec over NAT-T in this pane.

•

On the Fragmentation Policy parameter in the Configuration > Site-to-Site VPN > Advanced > IPsec
Prefragmentation Policies pane, edit the interface you will be using to Enable IPsec
pre-fragmentation. When this is configured, it is still alright to let traffic travel across NAT devices
that do not support IP fragmentation; they do not impede the operation of NAT devices that do.

Enable IPsec over TCP

IPsec over TCP enables a VPN client to operate in an environment in which standard ESP or IKE cannot
function, or can function only with modification to existing firewall rules. IPsec over TCP encapsulates
both the IKE and IPsec protocols within a TCP packet, and enables secure tunneling through both NAT
and PAT devices and firewalls. This feature is disabled by default.

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Note

This feature does not work with proxy-based firewalls.
IPsec over TCP works with remote access clients. It works on all physical and VLAN interfaces. It is a
client to ASA feature only. It does not work for LAN-to-LAN connections.
•

The ASA can simultaneously support standard IPsec, IPsec over TCP, NAT-Traversal, and IPsec
over UDP, depending on the client with which it is exchanging data.

•

The VPN 3002 hardware client, which supports one tunnel at a time, can connect using standard
IPsec, IPsec over TCP, NAT-Traversal, or IPsec over UDP.

•

When enabled, IPsec over TCP takes precedence over all other connection methods.

You enable IPsec over TCP on both the ASA and the client to which it connects.
You can enable IPsec over TCP for up to 10 ports that you specify. If you enter a well-known port, for
example port 80 (HTTP) or port 443 (HTTPS), the system displays a warning that the protocol associated
with that port will no longer work. The consequence is that you can no longer use a browser to manage
the ASA through the IKE-enabled interface. To solve this problem, reconfigure the HTTP/HTTPS
management to different ports.
You must configure TCP port(s) on the client as well as on the ASA. The client configuration must
include at least one of the ports you set for the ASA.

Identity Sent to Peer
Choose the Identity that the peers will use to identify themselves during IKE negotiations:
Address

Uses the IP addresses of the hosts exchanging ISAKMP identity information.

Hostname

Uses the fully-qualified domain name of the hosts exchanging ISAKMP identity
information (default). This name comprises the hostname and the domain name.

Key ID

Uses the remote peer uses the Key Id String that you specify to look up the preshared
key.

Automatic

Determines IKE negotiation by connection type:
•

IP address for preshared key

•

Cert DN for certificate authentication.

Session Control
Disable Inbound Aggressive Mode Connections

Phase 1 IKE negotiations can use either Main mode or Aggressive mode. Both provide the same services,
but Aggressive mode requires only two exchanges between the peers, rather than three. Aggressive mode
is faster, but does not provide identity protection for the communicating parties. It is therefore necessary
that they exchange identification information prior to establishing a secure SA in which to encrypt in
formation. This feature is disabled by default.
Alert Peers Before Disconnecting

Client or LAN-to-LAN sessions may be dropped for several reasons, such as: a ASA shutdown or reboot,
session idle timeout, maximum connection time exceeded, or administrator cut-off.

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Setting IKE Parameters for Site-to-Site VPN

The ASA can notify qualified peers (in LAN-to-LAN configurations), VPN Clients and VPN 3002
hardware clients of sessions that are about to be disconnected, and it conveys to them the reason. The
peer or client receiving the alert decodes the reason and displays it in the event log or in a pop-up pane.
This feature is disabled by default.
This pane lets you enable the feature so that the ASA sends these alerts, and conveys the reason for the
disconnect.
Qualified clients and peers include the following:
•

Security appliances with Alerts enabled.

•

VPN clients running 4.0 or later software (no configuration required).

•

VPN 3002 hardware clients running 4.0 or later software, and with Alerts enabled.

•

VPN 3000 concentrators running 4.0 or later software, with Alerts enabled.

Wait for All Active Sessions to Voluntarily Terminate Before Rebooting

You can schedule a ASA reboot to occur only when all active sessions have terminated voluntarily. This
feature is disabled by default.
Number of SAs Allowed in Negotiation for IKEv1

Limits the maximum number of SAs that can be in negotiation at any time.

IKE v2 Specific Settings
Additional session controls are available for IKE v2, that limit the number of open SAs. By default, the
ASA does not limit the number of open SAs:
•

Cookie Challenge—Enables the ASA to send cookie challenges to peer devices in response to SA
initiate packets.
– % threshold before incoming SAs are cookie challenged—The percentage of the total allowed

SAs for the ASA that are in-negotiation, which triggers cookie challenges for any future SA
negotiations. The range is zero to 100%. The default is 50%.
•

Number of Allowed SAs in Negotiation—Limits the maximum number of SAs that can be in
negotiation at any time. If used in conjunction with Cookie Challenge, configure the cookie
challenge threshold lower than this limit for an effective cross-check.

•

Maximum Number of SAs Allowed—Limits the number of allowed IKEv2 connections on the ASA.
By default, the limit is the maximum number of connections specified by the license.

Preventing DoS Attacks with IKE v2 Specific Settings
You can prevent denial-of-service (DoS) attacks for IPsec IKEv2 connections by configuring Cookie
Challenge, which challenges the identify of incoming Security Associations (SAs), or by limiting the
number of open SAs. By default, the ASA does not limit the number of open SAs, and never cookie
challenges SAs. You can also limit the number of SAs allowed, which stops further connections from
negotiating to protect against memory and/or CPU attacks that the cookie-challenge feature may be
unable to thwart and protects the current connections.
With a DoS attack, an attacker initiates the attack when the peer device sends an SA initiate packet and
the ASA sends its response, but the peer device does not respond further. If the peer device does this
continually, all the allowed SA requests on the ASA can be used up until it stops responding.

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Creating IKE Policies

Enabling a threshold percentage for cookie challenging limits the number of open SA negotiations. For
example, with the default setting of 50%, when 50% of the allowed SAs are in-negotiation (open), the
ASA cookie challenges any additional SA initiate packets that arrive. For the Cisco ASA 5580 with
10000 allowed IKEv2 SAs, after 5000 SAs become open, any more incoming SAs are
cookie-challenged.
If used in conjunction with the Number of SAs Allowed in Negotiation, or the Maximum Number of
SAs Allowed, configure the cookie-challenge threshold lower than these settings for an effective
cross-check.
You can also limit the life on all SAs at the IPsec level by choosing Configuration > Site-to-Site VPN >
Advanced > System Options.

Creating IKE Policies
About IKE
Each IKE negotiation is divided into two sections called Phase1 and Phase 2.
Phase 1 creates the first tunnel, which protects later IKE negotiation messages. Phase 2 creates the tunnel
that protects data.
To set the terms of the IKE negotiations, you create one or more IKE policies, which include the
following:
•

A unique priority (1 through 65,543, with 1 the highest priority).

•

An authentication method, to ensure the identity of the peers.

•

An encryption method, to protect the data and ensure privacy.

•

An HMAC method to ensure the identity of the sender, and to ensure that the message has not been
modified in transit.

•

A Diffie-Hellman group to establish the strength of the of the encryption-key-determination
algorithm. The ASA uses this algorithm to derive the encryption and hash keys.

•

A limit for how long the ASA uses an encryption key before replacing it.

For IKEv1, you can only enable one setting for each parameter. For IKEv2, each proposal can have
multiples settings for Encryption, D-H Group, Integrity Hash, and PRF Hash.
If you do not configure any IKE policies, the ASA uses the default policy, which is always set to the
lowest priority, and which contains the default value for each parameter. If you do not specify a value
for a specific parameter, the default value takes effect.
When IKE negotiation begins, the peer that initiates the negotiation sends all of its policies to the remote
peer, and the remote peer searches for a match with its own policies, in priority order.
A match between IKE policies exists if they have the same encryption, hash, authentication, and
Diffie-Hellman values, and an SA lifetime less than or equal to the lifetime in the policy sent. If the
lifetimes are not identical, the shorter lifetime—from the remote peer policy—applies. If no match
exists, IKE refuses negotiation and the IKE SA is not established.

Configuring IKE Policies
Configuration > Remote Access VPN > Network (Client) Access > Advanced > IPsec > IKE Policies

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Configuration > Site-to-Site VPN > Advanced > IKE Policies
Fields
•

IKEv1 Policies—Displays parameter settings for each configured IKE policy.
– Priority #—Shows the priority of the policy.
– Encryption—Shows the encryption method.
– Hash—Shows the hash algorithm.
– D-H Group—Shows the Diffie-Hellman group.
– Authentication—Shows the authentication method.
– Lifetime (secs)—Shows the SA lifetime in seconds.

•

Add/Edit/Delete—Click to add, edit, or delete an IKEv1 policy.

•

IKEv2 Policies—Displays parameter settings for each configured IKEv2 policy.
– Priority #—Shows the priority of the policy.
– Encryption—Shows the encryption method.
– Integrity Hash—Shows the hash algorithm.
– PRF Hash—Shows the pseudo random function (PRF) hash algorithm.
– D-H Group—Shows the Diffie-Hellman group.
– Lifetime (secs)—Shows the SA lifetime in seconds.

•

Add/Edit/Delete—Click to add, edit, or delete an IKEv2 policy.

Adding an IKEv1 Policy
Configuration > VPN > IKE > Policies > Add/Edit IKEv1 Policy
Fields

Priority #—Type a number to set a priority for the IKE policy. The range is 1 to 65535, with 1 the highest
priority.
Encryption—Choose an encryption method. This is a symmetric encryption method that protects data
transmitted between two IPsec peers.The choices follow:
des

56-bit DES-CBC. Less secure but faster than the alternatives. The default.

3des

168-bit Triple DES.

aes

128-bit AES.

aes-192

192-bit AES.

aes-256

256-bit AES.

Hash—Choose the hash algorithm that ensures data integrity. It ensures that a packet comes from whom
you think it comes from, and that it has not been modified in transit.
sha

SHA-1

md5

MD5

The default is SHA-1. MD5 has a smaller digest and is considered to
be slightly faster than SHA-1. A successful (but extremely difficult)
attack against MD5 has occurred; however, the HMAC variant IKE
uses prevents this attack.

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Authentication—Choose the authentication method the ASA uses to establish the identity of each IPsec
peer. Preshared keys do not scale well with a growing network but are easier to set up in a small network.
The choices follow:
pre-share

Preshared keys.

rsa-sig

A digital certificate with keys generated by the RSA signatures algorithm.

crack

IKE Challenge/Response for Authenticated Cryptographic Keys protocol for mobile
IPsec-enabled clients which use authentication techniques other than certificates.

D-H Group—Choose the Diffie-Hellman group identifier, which the two IPsec peers use to derive a
shared secret without transmitting it to each other.
1

Group 1 (768-bit)

2

Group 2 (1024-bit)

5

Group 5 (1536-bit)

The default, Group 2 (1024-bit Diffie-Hellman) requires less
CPU time to execute but is less secure than Group 1or 5.

Lifetime (secs)—Either check Unlimited or enter an integer for the SA lifetime. The default is 86,400
seconds or 24 hours. With longer lifetimes, the ASA sets up future IPsec security associations less
quickly. Encryption strength is great enough to ensure security without using very fast rekey times, on
the order of every few minutes. We recommend that you accept the default.
Time Measure—Choose a time measure. The ASA accepts the following values:.
120 - 86,400 seconds
2 - 1440 minutes
1 - 24 hours
1 day

Adding an IKEv2 Policy
Configuration > VPN > IKE > Policies > Add/Edit IKEv2 Policy
Fields

Priority #—Type a number to set a priority for the IKEv2 policy. The range is 1 to 65535, with 1 the
highest priority.
Encryption—Choose an encryption method. This is a symmetric encryption method that protects data
transmitted between two IPsec peers.The choices follow:
des

Specifies 56-bit DES-CBC encryption for ESP.

3des

(Default) Specifies the triple DES encryption algorithm for ESP.

aes

Specifies AES with a 128-bit key encryption for ESP.

aes-192

Specifies AES with a 192-bit key encryption for ESP.

aes-256

Specifies AES with a 256-bit key encryption for ESP.

aes-gcm

Specifies AES-GCM/GMAC 128-bit support for symmetric encryption and
integrity.

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aes-gcm-192

Specifies AES-GCM/GMAC 192-bit support for symmetric encryption and
integrity.

aes-gcm-256

Specifies AES-GCM/GMAC 256-bit support for symmetric encryption and
integrity.

NULL

Indicates no encryption.

D-H Group—Choose the Diffie-Hellman group identifier, which the two IPsec peers use to derive a
shared secret without transmitting it to each other.
1

Group 1 (768-bit)

2

Group 2 (1024-bit)

5

Group 5 (1536-bit)

14

Group 14

19

Group 19

20

Group 20

21

Group 21

24

Group 24

The default, Group 2 (1024-bit Diffie-Hellman) requires less
CPU time to execute but is less secure than Group 2 or 5.

Integrity Hash—Choose the hash algorithm that ensures data integrity for the ESP protocol. It ensures
that a packet comes from whom you think it comes from, and that it has not been modified in transit.
sha

SHA 1

md5

MD5

sha256

SHA 2, 256-bit
digest

Specifies the Secure Hash Algorithm SHA 2 with the 256-bit digest.

sha384

SHA 2, 384-bit
digest

Specifies the Secure Hash Algorithm SHA 2 with the 384-bit digest.

sha512

SHA 2, 512-bit
digest

Specifies the Secure Hash Algorithm SHA 2 with the 512-bit digest.

null

The default is SHA 1. MD5 has a smaller digest and is considered to
be slightly faster than SHA 1. A successful (but extremely difficult)
attack against MD5 has occurred; however, the HMAC variant IKE
uses prevents this attack.

Indicates that AES-GCM or AES-GMAC is configured as the
encryption algorithm. You must choose the null integrity algorithm if
AES-GCM has been configured as the encryption algorithm.

Pseudo-Random Function (PRF)—Specify the PRF used for the construction of keying material for all
of the cryptographic algorithms used in the SA..
sha

SHA-1

md5

MD5

sha256

SHA 2, 256-bit
digest

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The default is SHA-1. MD5 has a smaller digest and is considered to
be slightly faster than SHA-1. A successful (but extremely difficult)
attack against MD5 has occurred; however, the HMAC variant IKE
uses prevents this attack.
Specifies the Secure Hash Algorithm SHA 2 with the 256-bit digest.

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Configuring IPsec

sha384

SHA 2, 384-bit
digest

Specifies the Secure Hash Algorithm SHA 2 with the 384-bit digest.

sha512

SHA 2, 512-bit
digest

Specifies the Secure Hash Algorithm SHA 2 with the 512-bit digest.

Lifetime (secs)—Either check Unlimited or enter an integer for the SA lifetime. The default is 86,400
seconds or 24 hours. With longer lifetimes, the ASA sets up future IPsec security associations more
quickly. Encryption strength is great enough to ensure security without using very fast rekey times, on
the order of every few minutes. We recommend that you accept the default.
The ASA accepts the following values:.
120 - 86,400 seconds
2 - 1440 minutes
1 - 24 hours
1 day

Assignment Policy
Configuration > Remote Access VPN > Network (Client) Access > Address Assignment > Assignment
Policy
The Assignment Policy configures how IP addresses are assigned to remote access clients.
Fields
•

Use authentication server—Choose to assign IP addresses retrieved from an authentication server
on a per-user basis. If you are using an authentication server (external or internal) that has IP
addresses configured, we recommend using this method. Authorization servers are configured in the
Configuration > Remote Access VPN > AAA/Local Users > AAA Server Groups pane.

•

Use DHCP— Choose to obtain IP addresses from a DHCP server. If you use DHCP, configure the
server in the Configuration > Remote Access VPN > DHCP Server pane.

•

Use internal address pools—Choose to have the ASA assign IP addresses from an internally
configured pool. Internally configured address pools are the easiest method of address pool
assignment to configure. If you use this method, configure the IP address pools in Configuration >
Remote Access VPN > Network (Client) Access > Address Assignment > Address Pools pane.
– Allow the reuse of an IP address __ minutes after it is released—Delays the reuse of an IP

address after its return to the address pool. Adding a delay helps to prevent problems firewalls
can experience when an IP address is reassigned quickly. By default, this is unchecked, meaning
the ASA does not impose a delay. To add a delay, check the box and enter the number of minutes
in the range 1 - 480 to delay IP address reassignment.

Configuring IPsec
The ASA uses IPsec for LAN-to-LAN VPN connections, and provides the option of using IPsec for
client-to-LAN VPN connections. In IPsec terminology, a “peer” is a remote-access client or another
secure gateway.

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Configuring IPsec

Note

The ASA supports LAN-to-LAN IPsec connections with Cisco peers (IPv4 or IPv6), and with third-party
peers that comply with all relevant standards.
During tunnel establishment, the two peers negotiate security associations that govern authentication,
encryption, encapsulation, and key management. These negotiations involve two phases: first, to
establish the tunnel (the IKE SA); and second, to govern traffic within the tunnel (the IPsec SA).
A LAN-to-LAN VPN connects networks in different geographic locations. In IPsec LAN-to-LAN
connections, the ASA can function as initiator or responder. In IPsec client-to-LAN connections, the
ASA functions only as responder. Initiators propose SAs; responders accept, reject, or make
counter-proposals—all in accordance with configured SA parameters. To establish a connection, both
entities must agree on the SAs.
The ASA supports these IPsec attributes:
•

Main mode for negotiating phase one ISAKMP security associations when using digital certificates
for authentication

•

Aggressive mode for negotiating phase one ISAKMP Security Associations (SAs) when using
preshared keys for authentication

•

Authentication Algorithms:
– ESP-MD5-HMAC-128
– ESP-SHA1-HMAC-160

•

Authentication Modes:
– Preshared Keys
– X.509 Digital Certificates

•

Diffie-Hellman Groups 1, 2, and 5.

•

Encryption Algorithms:
– AES-128, -192, and -256
– 3DES-168
– DES-56
– ESP-NULL

•

Extended Authentication (XAuth)

•

Mode Configuration (also known as ISAKMP Configuration Method)

•

Tunnel Encapsulation Mode

•

IP compression (IPCOMP) using LZS

Adding Crypto Maps
Configuration > Remote Access VPN > Network (Client) Access > Advanced > IPsec > Crypto
Maps
This pane shows the currently configured crypto maps, which are defined in IPsec rules. Here you can
add, edit, delete and move up, move down, cut, copy, and paste an IPsec rule.

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Fields

Note

You cannot edit, delete, or copy an implicit rule. The ASA implicitly accepts the traffic selection
proposal from remote clients when configured with a dynamic tunnel policy. You can override it by
giving a specific traffic selection.
•

Add—Click to launch the Create IPsec Rule dialog box, where you can configure basic, advanced,
and traffic selection parameters for a rule.

•

Edit—Click to edit an existing rule.

•

Delete—Click to delete a rule highlighted in the table.

•

Cut—Deletes a highlighted rule in the table and keeps it in the clipboard for copying.

•

Copy—Copies a highlighted rule in the table.

•

Find—Click to enable the Find toolbar where you can specify the parameters of existing rules that
you want to find:
– Filter—Filter the find results by selecting Interface, Source, Destination, Destination Service,

or Rule Query, selecting is or contains, and entering the filter parameter. Click ... to launch a
browse dialog box that displays all existing entries that you can choose.
•

Diagram—Displays a diagram that illustrates the highlighted IPsec rule.

•

Type: Priority—Displays the type of rule (static or dynamic) and its priority.

•

Traffic Selection
– #—Indicates the rule number.
– Source—Indicates the IP addresses that are subject to this rule when traffic is sent to the IP

addresses listed in the Remote Side Host/Network column. In detail mode (see the Show Detail
button), an address column might contain an interface name with the word any, such as
inside:any. any means that any host on the inside interface is affected by the rule.
– Destination—Lists the IP addresses that are subject to this rule when traffic is sent from the IP

addresses listed in the Security Appliance Side Host/Network column. In detail mode (see the
Show Detail button), an address column might contain an interface name with the word any,
such as outside:any. any means that any host on the outside interface is affected by the rule. Also
in detail mode, an address column might contain IP addresses in square brackets, for example,
[209.165.201.1-209.165.201.30]. These addresses are translated addresses. When an inside host
makes a connection to an outside host, the ASA maps the inside host's address to an address
from the pool. After a host creates an outbound connection, the ASA maintains this address
mapping. This address mapping structure is called an xlate, and remains in memory for a period
of time.
– Service—Specifies the service and protocol specified by the rule (TCP, UDP, ICMP, or IP).
– Action—Specifies the type of IPsec rule (protect or do not protect).
•

Transform Set—Displays the transform set for the rule.

•

Peer—Identifies the IPsec peer.

•

PFS—Displays perfect forward secrecy settings for the rule.

•

NAT-T Enabled—Indicates whether NAT Traversal is enabled for the policy.

•

Reverse Route Enabled—Indicates whether Reverse Route Injection is enabled for the policy.

•

Connection Type—(Meaningful only for static tunnel policies.) Identifies the connection type for
this policy as bidirectional, originate-only, or answer-only).

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•

SA Lifetime—Displays the SA lifetime for the rule.

•

CA Certificate—Displays the CA certificate for the policy. This applies to static connections only.

•

IKE Negotiation Mode—Displays whether IKE negotiations use main or aggressive mode.

•

Description—(Optional) Specifies a brief description for this rule. For an existing rule, this is the
description you typed when you added the rule. An implicit rule includes the following description:
“Implicit rule.” To edit the description of any but an implicit rule, right-click this column, and
choose Edit Description or double-click the column.

•

Enable Anti-replay window size—Sets the anti-replay window size, between 64 and 1028 in
multiples of 64. One side-effect of priority queueing in a hierarchical QoS policy with traffic
shaping (see the “Rule Actions > QoS Tab”) is packet re-ordering. For IPsec packets, out-of-order
packets that are not within the anti-replay window generate warning syslog messages. These
warnings becomes false alarms in the case of priority queueing. Configuring the anti-replay pane
size helps you avoid possible false alarms.

Creating an IPsec Rule/Tunnel Policy (Crypto Map) - Basic Tab
Configuration > Remote Access VPN > Network (Client) Access > Advanced > IPsec > Crypto
Maps - Edit IPsec Rule - Basic Tab
Use this pane to define a new Tunnel Policy for an IPsec rule. The values you define here appear in the
IPsec Rules table after you click OK. All rules are enabled by default as soon as they appear in the IPsec
Rules table.
The Tunnel Policy pane lets you define a tunnel policy that is used to negotiate an IPsec (Phase 2)
security association (SA). ASDM captures your configuration edits, but does not save them to the
running configuration until you click Apply.
Every tunnel policy must specify a transform set and identify the security appliance interface to which
it applies. The transform set identifies the encryption and hash algorithms that perform IPsec encryption
and decryption operations. Because not every IPsec peer supports the same algorithms, you might want
to specify a number of policies and assign a priority to each. The security appliance then negotiates with
the remote IPsec peer to agree on a transform set that both peers support.
Tunnel policies can be static or dynamic. A static tunnel policy identifies one or more remote IPsec peers
or subnetworks to which your security appliance permits IPsec connections. A static policy can be used
whether your security appliance initiates the connection or receives a connection request from a remote
host. A static policy requires you to enter the information necessary to identify permitted hosts or
networks.
A dynamic tunnel policy is used when you cannot or do not want to provide information about remote
hosts that are permitted to initiate a connection with the security appliance. If you are only using your
security appliance as a VPN client in relation to a remote VPN central-site device, you do not need to
configure any dynamic tunnel policies. Dynamic tunnel policies are most useful for allowing remote
access clients to initiate a connection to your network through a security appliance acting as the VPN
central-site device. A dynamic tunnel policy is useful when the remote access clients have dynamically
assigned IP addresses or when you do not want to configure separate policies for a large number of
remote access clients.
Fields
•

Interface—Choose the interface name to which this policy applies.

•

Policy Type—Choose the type, static or dynamic, of this tunnel policy.

•

Priority—Enter the priority of the policy.

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Configuring IPsec

•

IKE Proposals (Transform Sets)--Specifies IKEv1 and IKEv2 IPsec proposals:
– IKEv1 IPsec Proposal—Choose the proposal (transform set) for the policy and click Add to

move it to the list of active transform sets. Click Move Up or Move Down to rearrange the order
of the proposals in the list box. You can add a maximum of 11 proposals to a crypto map entry
or a dynamic crypto map entry.
– IKEv2 IPsec Proposal—Choose the proposal (transform set) for the policy and click Add to

move it to the list of active transform sets. Click Move Up or Move Down to rearrange the order
of the proposals in the list box. You can add a maximum of 11 proposals to a crypto map entry
or a dynamic crypto map entry.
•

Peer Settings - Optional for Dynamic Crypto Map Entries—Configure the peer settings for the
policy.
– Connection Type—(Meaningful only for static tunnel policies.) Choose bidirectional,

originate-only, or answer-only to specify the connection type of this policy. For LAN-to-LAN
connections, choose bidirectional or answer-only (not originate-only). Choose answer-only for
LAN-to-LAN redundancy. If you choose Originate Only, you can specify up to 10 redundant
peers. For uni-directional, you can specify originate only or answer only, and neither are
enabled by default.
– IP Address of Peer to Be Added—Enter the IP address of the IPsec peer you are adding.
•

Enable Perfect Forwarding Secrecy—Check to enable perfect forward secrecy for the policy. PFS is
a cryptographic concept where each new key is unrelated to any previous key. In IPsec negotiations,
Phase 2 keys are based on Phase 1 keys unless you specify Perfect Forward Secrecy.

•

Diffie-Hellman Group—When you enable PFS you must also choose a Diffie-Hellman group which
the ASA uses to generate session keys. The choices are as follows:
– Group 1 (768-bits) = Use perfect forward secrecy, and use Diffie-Hellman Group 1 to generate

IPsec session keys, where the prime and generator numbers are 768 bits. This option is more
secure but requires more processing overhead.
– Group 2 (1024-bits) = Use perfect forward secrecy, and use Diffie-Hellman Group 2 to generate

IPsec session keys, where the prime and generator numbers are 1024 bits. This option is more
secure than Group 1 but requires more processing overhead.
– Group 5 (1536-bits) = Use perfect forward secrecy, and use Diffie-Hellman Group 5 to generate

IPsec session keys, where the prime and generator numbers are 1536 bits. This option is more
secure than Group 2 but requires more processing overhead.
– Group 14= Use perfect forward secrecy and use Diffie-Hellman Group 14 for IKEv2.
– Group 19= Use perfect forward secrecy and use Diffie-Hellman Group 19 for IKEv2 to support

ECDH.
– Group 20= Use perfect forward secrecy and use Diffie-Hellman Group 20 for IKEv2 to support

ECDH.
– Group 21= Use perfect forward secrecy and use Diffie-Hellman Group 21 for IKEv2 to support

ECDH.
– Group 24= Use perfect forward secrecy and use Diffie-Hellman Group 24 for IKEv2.

Creating IPsec Rule/Tunnel Policy (Crypto Map) - Advanced Tab
Configuration > Remote Access VPN > Network (Client) Access > Advanced > IPsec > Crypto
Maps - Edit IPsec Rule - Advanced Tab

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Fields
•

Enable NAT-T— Enables NAT Traversal (NAT-T) for this policy.

•

Enable Reverse Route Injection—Enables Reverse Route Injection for this policy.
Reverse Route Injection (RRI) is used to populate the routing table of an internal router that runs
dynamic routing protocols such as Open Shortest Path First (OSPF), or Enhanced Interior Gateway
Routing Protocol (EIGRP), if you run ASA, or Routing Information Protocol (RIP) for remote VPN
Clients or LAN to LAN sessions.

•

Security Association Lifetime Settings—Configures the duration of a Security Association (SA).
This parameter specifies how to measure the lifetime of the IPsec SA keys, which is how long the
IPsec SA lasts until it expires and must be renegotiated with new keys.
– Time—Specifies the SA lifetime in terms of hours (hh), minutes (mm) and seconds (ss).
– Traffic Volume—Defines the SA lifetime in terms of kilobytes of traffic. Enter the number of

kilobytes of payload data after which the IPsec SA expires. Minimum is 100 KB, default is
10000 KB, maximum is 2147483647 KB.
•

Static Type Only Settings—Specifies parameters for static tunnel policies.
– Device Certificate—Choose the certificate to use. If you choose something other than

None (Use Preshared Keys), which is the default. The Send CA certificate chain check box
becomes active when you select something other than None.
– Send CA certificate chain—Enables transmission of the entire trust point chain.
– IKE Negotiation Mode—Chooses the IKE negotiation mode, Main or Aggressive. This

parameter sets the mode for exchanging key information and setting up the SAs. It sets the mode
that the initiator of the negotiation uses; the responder auto-negotiates. Aggressive Mode is
faster, using fewer packets and fewer exchanges, but it does not protect the identity of the
communicating parties. Main Mode is slower, using more packets and more exchanges, but it
protects the identities of the communicating parties. This mode is more secure and it is the
default selection. If you choose Aggressive, the Diffie-Hellman Group list becomes active.
– Diffie-Hellman Group—Choose the Diffie-Hellman group to apply. The choices are as follows:

Group 1 (768-bits), Group 2 (1024-bits), or Group 5 (1536-bits).
•

ESP v3—Specify whether incoming ICMP error messages are validated for cryptography and
dynamic cryptography maps, set the per-security association policy, or enable traffic flow packets:
– Validate incoming ICMP error messages—Choose whether to validate those ICMP error

messages received through an IPsec tunnel and destined for an interior host on the private
network.
– Enable Do Not Fragment (DF) policy—Define how the IPsec subsystem handles large packets

that have the do-not-fragment (DF) bit set in the IP header. Choose one of the following:
Clear DF bit—Ignores the DF bit.
Copy DF bit—Maintains the DF bit.
Set DF bit—Sets and uses the DF bit.
– Enable Traffic Flow Confidentiality (TFC) packets—Enable dummy TFC packets that mask the

traffic profile which traverses the tunnel.

Note

You must have an IKE v2 IPsec proposal set on the Tunnel Policy (Crypto Map) Basic
tab before enabling TFC.

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Configuring IPsec

Use the Burst, Payload Size, and Timeout parameters to generate random length packets at
random intervals across the specified SA.

Creating IPsec Rule/Traffic Selection Tab
Configuration > VPN > IPSec > IPSec Rules > Add/Edit Rule > Tunnel Policy (Crypto Map) Traffic Selection Tab
This pane lets you define what traffic to protect (permit) or not protect (deny).
Fields
•

Action—Specify the action for this rule to take. The selections are protect and do not protect.

•

Source—Specify the IP address, network object group or interface IP address for the source host or
network. A rule cannot use the same address as both the source and destination. Click ... to launch
the Browse Source dialog box that contains the following fields:
– Add/Edit—Choose IP Address or Network Object Group to add more source addresses or

groups.
– Delete—Click to delete an entry.
– Filter—Enter an IP Address to filter the results displayed.
– Name—Indicates that the parameters that follow specify the name of the source host or network.
– IP Address—Indicates that the parameters that follow specify the interface, IP address, and

subnet mask of the source host or network.
– Netmask—Chooses a standard subnet mask to apply to the IP address. This parameter appears

when you choose the IP Address option button.
– Description—Enter a description.
– Selected Source—Click Source to include the selected entry as a source.
•

Destination—Specify the IP address, network object group or interface IP address for the
destination host or network. A rule cannot use the same address as both the source and destination.
Click ... to launch the Browse Destination dialog box that contains the following fields:
– Add/Edit—Choose IP Address or Network Object Group to add more destination addresses or

groups.
– Delete—Click to delete an entry.
– Filter—Enter an IP Address to filter the results displayed.
– Name—Indicates that the parameters that follow specify the name of the destination host or

network.
– IP Address—Indicates that the parameters that follow specify the interface, IP address, and

subnet mask of the destination host or network.
– Netmask—Chooses a standard subnet mask to apply to the IP address. This parameter appears

when you choose the IP Address option button.
– Description—Enter a description.
– Selected Destination—Click Destination to include the selected entry as a destination.
•

Service—Enter a service or click ... to launch the browse service dialog box where you can choose
from a list of services.

•

Description—Enter a description for the Traffic Selection entry.

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Configuring IPsec

•

More Options
– Enable Rule—Click to enable this rule.
– Source Service—Enter a service or click ... to launch the browse service dialog box where you

can choose from a list of services.
– Time Range—Define a time range for which this rule applies.
– Group—Indicates that the parameters that follow specify the interface and group name of the

source host or network.
– Interface—Choose the interface name for the IP address. This parameter appears when you

choose the IP Address option button.
– IP address—Specifies the IP address of the interface to which this policy applies. This

parameter appears when you choose the IP Address option button.
– Destination—Specify the IP address, network object group or interface IP address for the source

or destination host or network. A rule cannot use the same address as both the source and
destination. Click ... for either of these fields to launch the Browse dialog box that contain the
following fields:
– Name—Choose the interface name to use as the source or destination host or network. This

parameter appears when you choose the Name option button. This is the only parameter
associated with this option.
– Interface—Choose the interface name for the IP address. This parameter appears when you

choose the Group option button.
– Group—Choose the name of the group on the specified interface for the source or destination

host or network. If the list contains no entries, you can enter the name of an existing group. This
parameter appears when you choose the Group option button.
•

Note

Protocol and Service—Specifies protocol and service parameters relevant to this rule.

“Any - any” IPsec rules are not allowed. This type of rule would prevent the device and its peer
from supporting multiple LAN -to-LAN tunnels.
– TCP—Specifies that this rule applies to TCP connections. This selection also displays the

Source Port and Destination Port group boxes.
– UDP—Specifies that this rule applies to UDP connections. This selection also displays the

Source Port and Destination Port group boxes.
– ICMP—Specifies that this rule applies to ICMP connections. This selection also displays the

ICMP Type group box.
– IP—Specifies that this rule applies to IP connections. This selection also displays the IP

Protocol group box.
– Manage Service Groups—Displays the Manage Service Groups pane, on which you can add,

edit, or delete a group of TCP/UDP services/ports.
– Source Port and Destination Port —Contains TCP or UDP port parameters, depending on

which option button you chose in the Protocol and Service group box.
– Service—Indicates that you are specifying parameters for an individual service. Specifies the

name of the service and a boolean operator to use when applying the filter.
– Boolean operator (unlabeled)—Lists the boolean conditions (equal, not equal, greater than,

less than, or range) to use in matching the service specified in the service box.

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Configuring IPsec

– Service (unlabeled)—Identifies the service (such as https, kerberos, or any) to be matched. If

you specified the range service operator this parameter becomes two boxes, into which you
enter the start and the end of the range.
– ... —Displays a list of services from which you can choose the service to display in the Service

box.
– Service Group—Indicates that you are specifying the name of a service group for the source

port.
– Service (unlabeled)—Choose the service group to use.
– ICMP Type—Specifies the ICMP type to use. The default is any. Click the ... button to display

a list of available types.
•

Options
– Time Range—Specify the name of an existing time range or create a new range.
– ... —Displays the Add Time Range pane, on which you can define a new time range.
– Please enter the description below (optional)—Provides space for you to enter a brief

description of the rule.

Pre-Fragmentation
Configuration > VPN > IPSec > Pre-Fragmentation
Use this pane to set the IPsec pre-fragmentation policy and do-not-fragment (DF) bit policy for any
interface.
The IPsec pre-fragmentation policy specifies how to treat packets that exceed the maximum transmission
unit (MTU) setting when tunneling traffic through the public interface. This feature provides a way to
handle cases where a router or NAT device between the ASA and the client rejects or drops IP fragments.
For example, suppose a client wants to FTP get from an FTP server behind a ASA. The FTP server
transmits packets that when encapsulated would exceed the ASA’s MTU size on the public interface.
The selected options determine how the ASA processes these packets. The pre-fragmentation policy
applies to all traffic travelling out the ASA public interface.
The ASA encapsulates all tunneled packets. After encapsulation, the ASA fragments packets that exceed
the MTU setting before transmitting them through the public interface. This is the default policy. This
option works for situations where fragmented packets are allowed through the tunnel without hindrance.
For the FTP example, large packets are encapsulated and then fragmented at the IP layer. Intermediate
devices may drop fragments or just out-of-order fragments. Load-balancing devices can introduce
out-of-order fragments.
When you enable pre-fragmentation, the ASA fragments tunneled packets that exceed the MTU setting
before encapsulating them. If the DF bit on these packets is set, the ASA clears the DF bit, fragments
the packets, and then encapsulates them. This action creates two independent non-fragmented IP packets
leaving the public interface and successfully transmits these packets to the peer site by turning the
fragments into complete packets to be reassembled at the peer site. In our example, the ASA overrides
the MTU and allows fragmentation by clearing the DF bit.

Note

Changing the MTU or the pre-fragmentation option on any interface tears down all existing connections.
For example, if 100 active tunnels terminate on the public interface, and you change the MTU or the
pre-fragmentation option on the external interface, all of the active tunnels on the public interface are
dropped.

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Fields
•

Pre-Fragmentation—Shows the current pre-fragmentation configuration for every configured
interface.
– Interface—Shows the name of each configured interface.
– Pre-Fragmentation Enabled—Shows, for each interface, whether pre-fragmentation is

enabled.
– DF Bit Policy—Shows the DF Bit Policy for each interface.
•

Edit—Displays the Edit IPsec Pre-Fragmentation Policy dialog box.

Edit IPsec Pre-Fragmentation Policy
Configuration > VPN > IPSec > Pre-Fragmentation > Edit IPSec Pre-Fragmentation Policy
Use this pane to modify an existing IPsec pre-fragmentation policy and do-not-fragment (DF) bit policy
for an interface selected on the parent pane, Configuration > VPN > IPsec > Pre-Fragmentation
Fields
•

Interface—Identifies the chosen interface. You cannot change this parameter using this dialog box.

•

Enable IPsec pre-fragmentation—Enables or disables IPsec pre-fragmentation. The ASA
fragments tunneled packets that exceed the MTU setting before encapsulating them. If the DF bit on
these packets is set, the ASA clears the DF bit, fragments the packets, and then encapsulates them.
This action creates two independent, non-fragmented IP packets leaving the public interface and
successfully transmits these packets to the peer site by turning the fragments into complete packets
to be reassembled at the peer site.

•

DF Bit Setting Policy—Choose the do-not-fragment bit policy: Copy, Clear, or Set.

IPsec Transform Sets
Configuration > VPN > IPSec > Transform Sets
Use this pane to view and add or edit transform sets. A transform is a set of operations done on a data
flow to provide data authentication, data confidentiality, and data compression. For example, one
transform is the ESP protocol with 3DES encryption and the HMAC-MD5 authentication algorithm
(ESP-3DES-MD5).
Fields
•

IKEv1 IPsec Proposals (Transform Sets)—Shows the configured transform sets.
– Name—Shows the name of the transform sets.
– Mode—Shows the mode, Tunnel, of the transform set. This parameter specifies the mode for

applying ESP encryption and authentication; in other words, what part of the original IP packet
has ESP applied. Tunnel mode applies ESP encryption and authentication to the entire original
IP packet (IP header and data), thus hiding the ultimate source and destination addresses.
– ESP Encryption—Shows the Encapsulating Security Protocol (ESP) encryption algorithms for

the transform sets. ESP provides data privacy services, optional data authentication, and
anti-replay services. ESP encapsulates the data being protected.
– ESP Authentication—Shows the ESP authentication algorithms for the transform sets.
•

Add—Opens the Add Transform Set dialog box, in which you can add a new transform set.

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•

Edit—Opens the Edit Transform Set dialog box, in which you can modify an existing transform set.

•

Delete—Removes the selected transform set. There is no confirmation or undo.

•

IKEv2 IPsec Proposals—Shows the configured transform sets.
– Name—Shows the name of the IKEv2 IPsec Proposal.
– Encryption—Shows the Encapsulating Security Protocol (ESP) encryption algorithms for the

IKEv2 IPsec Proposal. ESP provides data privacy services, optional data authentication, and
anti-replay services. ESP encapsulates the data being protected.
– Integrity Hash—Shows the hash algorithm that ensures data integrity for the ESP protocol. It

ensures that a packet comes from whom you would expect and that no modifications were made
in transit. It ensures that a packet comes from who you would expect and that no modifications
were made in transit. You must choose the null integrity algorithm if AES-GCM/GMAC has
been configured as the encryption algorithm.
•

Add—Opens the Add IPsec Proposal dialog box, in which you can add a new proposal.

•

Edit—Opens the Edit IPsec Proposal dialog box, in which you can modify an existing proposal.

•

Delete—Removes the selected proposal. There is no confirmation or undo.

Add/Edit IPsec Proposal (Transform Set)
(Configuration > VPN > IPSec > Transform Sets > Add/Edit IPsec_Proposal_(Transform Set)
Use this pane to add or modify an IPsec IKEv1 transform set. A transform is a set of operations done on
a data flow to provide data authentication, data confidentiality, and data compression. For example, one
transform is the ESP protocol with 3DES encryption and the HMAC-MD5 authentication algorithm
(ESP-3DES-MD5).
Fields
•

Set Name—Specifies a name for this transform set.

•

Properties—Configures properties for this transform set. These properties appear in the Transform
Sets table.
– Mode—Shows the mode, Tunnel, of the transform set. This field shows the mode for applying

ESP encryption and authentication; in other words, what part of the original IP packet has ESP
applied. Tunnel mode applies ESP encryption and authentication to the entire original IP packet
(IP header and data), thus hiding the ultimate source and destination addresses.
– ESP Encryption—Choose the Encapsulating Security Protocol (ESP) encryption algorithms

for the transform sets. ESP provides data privacy services, optional data authentication, and
anti-replay services. ESP encapsulates the data being protected.
– ESP Authentication—Choose the ESP authentication algorithms for the transform sets.

Note

The IPsec ESP (Encapsulating Security Payload) protocol provides both encryption and
authentication. Packet authentication proves that data comes from whom you think it comes
from; it is often referred to as “data integrity.”

Add/Edit IPsec Proposal
Configuration > VPN > IPSec > Transform Sets > Add/Edit IPsec_Proposal

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Use this pane to add or modify an IPsec IKEv2 proposal. A proposal is a set of operations done on a data
flow to provide data authentication, data confidentiality, and data compression. For example, one
proposal is the ESP protocol with 3DES encryption and the HMAC-MD5 authentication algorithm
(ESP-3DES-MD5).
Fields
•

Name—Specifies a name for this proposal.

•

Encryption—Choose the Encapsulating Security Protocol (ESP) encryption algorithms for the
proposal. ESP provides data privacy services, optional data authentication, and anti-replay services.
ESP encapsulates the data being protected.

•

Integrity Hash—Choose the ESP authentication algorithms for the proposal. The hash algorithm
ensures data integrity for the ESP protocol. It ensures that a packet comes from whom you think it
comes from, and that it has not been modified in transit.

Note

The IPsec ESP (Encapsulating Security Payload) protocol provides both encryption and
authentication. Packet authentication proves that data comes from whom you think it comes
from; it is often referred to as “data integrity.”

Configuring Load Balancing
If you have a remote-client configuration in which you are using two or more ASAs connected to the
same network to handle remote sessions, you can configure these devices to share their session load. This
feature is called load balancing. Load balancing directs session traffic to the least loaded device, thus
distributing the load among all devices. It makes efficient use of system resources and provides increased
performance anodize availability.
The following sections explain load balancing:
•

Creating Virtual Clusters

•

Geographical Load Balancing

•

Comparing Load Balancing to Failover

•

Load Balancing Licensing Requirements

•

Load Balancing Prerequisites

•

Eligible Clients

•

Configuring VPN Cluster Load Balancing with the High Availability and Scalability Wizard

•

Configuring Load Balancing (Without the Wizard)

Creating Virtual Clusters
To implement load balancing, you group together logically two or more devices on the same private
LAN-to-LAN network into a virtual cluster.

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All devices in the virtual cluster carry session loads. One device in the virtual cluster, the virtual cluster
master, directs incoming connection requests to the other devices, called backup devices. The virtual
cluster master monitors all devices in the cluster, keeps track of how busy each is, and distributes the
session load accordingly. The role of virtual cluster master is not tied to a physical device; it can shift
among devices. For example, if the current virtual cluster master fails, one of the backup devices in the
cluster takes over that role and immediately becomes the new virtual cluster master.
The virtual cluster appears to outside clients as a single virtual cluster IP address. This IP address is not
tied to a specific physical device. It belongs to the current virtual cluster master; hence, it is virtual. A
VPN client attempting to establish a connection connects first to this virtual cluster IP address. The
virtual cluster master then sends back to the client the public IP address of the least-loaded available host
in the cluster. In a second transaction (transparent to the user) the client connects directly to that host.
In this way, the virtual cluster master directs traffic evenly and efficiently across resources.
If a machine in the cluster fails, the terminated sessions can immediately reconnect to the virtual cluster
IP address. The virtual cluster master then directs these connections to another active device in the
cluster. Should the virtual cluster master itself fail, a backup device in the cluster immediately and
automatically takes over as the new virtual session master. Even if several devices in the cluster fail,
users can continue to connect to the cluster as long as any one device in the cluster is up and available.
A load-balancing cluster can consist of ASAs of the same release or of mixed releases subject to the
following restrictions:
•

Load-balancing clusters that consist of both same release ASAs can run load balancing for a mixture
of IPsec, AnyConnect, and clientless SSL VPN client and clientless sessions.

•

Load-balancing clusters that include mixed release ASAs or same release ASAs can support only
IPsec sessions. In such a configuration, however, the ASAs might not reach their full IPsec capacity.
“Comparing Load Balancing to Failover” on page 22, illustrates this situation.

Since Release 7.1(1), IPsec and SSL VPN sessions count or weigh equally in determining the load that
each device in the cluster carries. This represents a departure from the load balancing calculation for the
ASA Release 7.0(x) software and the VPN 3000 concentrator, in that these platforms both use a
weighting algorithm that, on some hardware platforms, calculates SSL VPN session load differently
from IPsec session load.
The virtual master of the cluster assigns session requests to the members of the cluster. The ASA regards
all sessions, SSL VPN or IPsec, as equal and assigns them accordingly. You can configure the number
of IPsec and SSL VPN sessions to allow, up to the maximum allowed by your configuration and license.
We have tested up to ten nodes in a load-balancing cluster. Larger clusters might work, but we do not
officially support such topologies.

Geographical Load Balancing
In a load balancing environment where the DNS resolutions are being changed at regular intervals, you
must carefully consider how to set the time to live (TTL) value. For the DNS load balance configuration
to work successfully with AnyConnect, the ASA name to address mapping must remain the same from
the time the ASA is selected until the tunnel is fully established. If too much time passes before the
credentials are entered, the lookup restarts and a different IP address may become the resolved address.
If the DNS mapping changes to a different ASA before the credentials are entered, the VPN tunnel fails.
Geographical load balancing for VPN often uses a Cisco Global Site Selector (GSS). The GSS uses DNS
for the load balancing, and the time to live (TTL) value for DNS resolution is defaulted to 20 seconds.
You can significantly decrease the likelihood of connection failures if you increase the TTL value on the
GSS. Increasing to a much higher value allows ample time for the authentication phase when the user is
entering credentials and establishing the tunnel.

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To increase the time for entering credentials, you may also consider disabling Connect on Start Up.

Comparing Load Balancing to Failover
Both load balancing and failover are high-availability features, but they function differently and have
different requirements. In some circumstances you can use both load balancing and failover. The
following sections describe the differences between these features.
Load balancing is a mechanism for equitably distributing remote-access VPN traffic among the devices
in a virtual cluster. It is based on simple distribution of traffic without taking into account throughput or
other factors. A load-balancing cluster consists of two or more devices, one of which is the virtual
master, and the others backup. These devices do not need to be of the exact same type, or have identical
software versions or configurations. All active devices in a virtual cluster carry session loads. Load
balancing directs traffic to the least loaded device in the cluster, distributing the load among all devices.
It makes efficient use of system resources and provides increased performance and high availability.
A failover configuration requires two identical ASAs connected to each other through a dedicated
failover link and, optionally, a stateful failover link. The health of the active interfaces and units is
monitored to determine when specific failover conditions are met. If those conditions occur, failover
occurs. Failover supports both VPN and firewall configurations.
The ASA supports two failover configurations, Active/Active failover and Active/Standby failover. VPN
connections run only in Active/Standby, single routed mode. Active/Active failover requires
multi-context mode, so does not support VPN connections.
With Active/Active failover, both units can pass network traffic. This is not true with load balancing,
although it might appear to have the same effect. When failover occurs, the remaining active unit takes
over passing the combined traffic, based on the configured parameters. Therefore, when configuring
Active/Active failover, you must make sure that the combined traffic for both units is within the capacity
of each unit.
With Active/Standby failover, only one unit passes traffic, while the other unit waits in a standby state
and does not pass traffic. Active/Standby failover lets you use a second ASA to take over the functions
of a failed unit. When the active unit fails, it changes to the standby state, while the standby unit changes
to the active state. The unit that becomes active assumes the IP addresses (or, for transparent firewall,
the management IP address) and MAC addresses of the failed unit and begins passing traffic. The unit
that is now in standby state takes over the standby IP addresses of the active unit. If an active unit fails,
the standby takes over without any interruption to the client VPN tunnel.

Load Balancing Licensing Requirements
To use VPN load balancing, you must have an ASA Model 5510 with a Plus license or an ASA Model
5520 or higher. VPN load balancing also requires an active 3DES/AES license. The security appliance
checks for the existence of this crypto license before enabling load balancing. If it does not detect an
active 3DES or AES license, the security appliance prevents the enabling of load balancing and also
prevents internal configuration of 3DES by the load balancing system unless the license permits this
usage.

Eligible Clients
Load balancing is effective only on remote sessions initiated with the following clients:
•

Cisco AnyConnect Secure Mobility Client (Release 3.0 and later)

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•

Cisco ASA 5505 Security Appliance (when acting as an Easy VPN client)

•

IOS EZVPN Client devices supporting IKE-redirect (IOS 831/871)

•

Clientless SSL VPN (not a client)

Load balancing works with IPsec clients and SSL VPN client and clientless sessions. All other VPN
connection types (L2TP, PPTP, L2TP/IPsec), including LAN-to-LAN, can connect to an ASA on which
load balancing is enabled, but they cannot participate in load balancing.

Load Balancing Prerequisites
•

You must have first configured the ASA’s public and private interfaces before configuring load
balancing. To do so select Configuration > Device Setup > Interfaces. See Chapter 11, “Starting
Interface Configuration (ASA 5510 and Higher)” or Chapter 12, “Starting Interface Configuration
(ASA 5505)” in the general operations configuration guide for more information.

•

You must have previously configured the interface to which the virtual cluster IP address refers.

•

All devices that participate in a cluster must share the same cluster-specific values: IP address,
encryption settings, encryption key, and port. All of the outside and inside network interfaces on the
load-balancing devices in a cluster must be on the same IP network.

Certificate Verification
When performing certificate verification for load balancing with AnyConnect, and the connection is
redirected by an IP address, the client does all of its name checking through this IP address. Make sure
the redirection IP address is listed in the certificates common name or the subject alt name. If the IP
address is not present in these fields, then the certificate will be deemed untrusted.
Following the guidelines defined in RFC 2818, if a subject alt name is included in the certificate, we
only use the subject alt name for name checks, and we ignore the common name. Make sure that the IP
address of the server presenting the certificate is defined in the subject alt name of the certificate.
For a standalone ASA, the IP address is the IP of that ASA. In a clustering situation, it depends on the
certificate configuration. If the cluster uses one certificate, then it would be the IP of the cluster, and the
certificate would contain Subject Alternative Name extensions that have each ASA's IP and FQDN. If
the cluster uses multiple certificates, then it should once again be the IP address of the ASA.

Configuring VPN Cluster Load Balancing with the High Availability and
Scalability Wizard
If you have a remote-client configuration in which you are using two or more ASAs connected to the
same network to handle remote sessions, you can configure these devices to share their session load. This
feature is called load balancing, which directs session traffic to the least loaded device, thereby
distributing the load among all devices. Load balancing makes efficient use of system resources and
provides increased performance and system availability.
Use the VPN Cluster Load Balancing Configuration screen to set required parameters for a device to
participate in a load balancing cluster.
Enabling load balancing involves the following:

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Configuring Load Balancing

•

Configuring the load-balancing cluster by establishing a common virtual cluster IP address, UDP
port (if necessary), and IPsec shared secret for the cluster. These values are identical for each device
in the cluster.

•

Configuring the participating device by enabling load balancing on the device and defining
device-specific properties. These values vary from device to device.

Prerequisites

If you are using encryption, you must configure the load balancing inside interface. If that interface is
not enabled on the load balancing inside interface, an error message appears when you try to configure
cluster encryption.
Detailed Steps

To implement load balancing, you logically group together two or more devices on the same private
LAN-to-LAN network into a virtual cluster by performing the following steps:
Step 1

Choose Wizards > High Availability and Scalability.

Step 2

In the Configuration Type screen, click Configure VPN Cluster Load Balancing, and click Next.

Step 3

Choose the single IP address that represents the entire virtual cluster. Specify an IP address that is within
the public subnet address range shared by all the ASAs in the virtual cluster.

Step 4

Specify the UDP port for the virtual cluster in which this device is participating. The default value is
9023. If another application is using this port, enter the UDP destination port number that you want to
use for load balancing.

Step 5

To enable IPsec encryption and ensure that all load-balancing information communicated between the
devices is encrypted, check the Enable IPsec Encryption check box. You must also specify and verify
a shared secret. The ASAs in the virtual cluster communicate via LAN-to-LAN tunnels using IPsec. To
disable IPsec encryption, uncheck the Enable IPsec Encryption check box.

Step 6

Specify the shared secret to between IPsec peers when you enable IPsec encryption. The value that you
enter appears as consecutive asterisk characters.

Step 7

Specify the priority assigned to this device within the cluster. The range is from 1 to 10. The priority
indicates the likelihood of this device becoming the virtual cluster master, either at startup or when an
existing master fails. The higher the priority set (for example, 10), the more likely that this device will
become the virtual cluster master.

Note

If the devices in the virtual cluster are powered up at different times, the first device to be
powered up assumes the role of virtual cluster master. Because every virtual cluster requires a
master, each device in the virtual cluster checks when it is powered up to ensure that the cluster
has a virtual master. If none exists, that device assumes the role. Devices powered up and added
to the cluster later become secondary devices. If all the devices in the virtual cluster are powered
up simultaneously, the device with the highest priority setting becomes the virtual cluster master.
If two or more devices in the virtual cluster are powered up simultaneously, and both have the
highest priority setting, the one with the lowest IP address becomes the virtual cluster master.

Step 8

Specify the name or IP address of the public interface for this device.

Step 9

Specify the name or IP address of the private interface for this device.

Step 10

Check the Send FQDN to client instead of an IP address when redirecting check box to have the VPN
cluster master send a fully qualified domain name using the host and domain name of the cluster device
instead of the outside IP address when redirecting VPN client connections to that cluster device.

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Configuring Load Balancing

Step 11

Click Next. Review your configuration in the Summary screen.

Step 12

Click Finish.
The VPN cluster load balancing configuration is sent to the ASA.

Configuring Load Balancing (Without the Wizard)
The Load Balancing pane (Configuration > Remote Access VPN > Load Balancing) lets you enable load
balancing on the ASA. Enabling load balancing involves:
•

Configuring the load-balancing cluster by establishing a common virtual cluster IP address, UDP
port (if necessary), and IPsec shared secret for the cluster. These values are identical for every device
in the cluster.

•

Configuring the participating device by enabling load balancing on the device and defining
device-specific properties. These values vary from device to device.

Prerequisite
•

For clients with IPv6 addresses to successfully connect to the ASA’s public-facing IPv4 address, a
device that can perform network address translation from IPv6 to IPv4 needs to be in the network.

•

If you are using encryption, you must configure the load balancing inside interface. If that interface
is not enabled on the load balancing inside interface, an error message appears when you try to
configure cluster encryption.

Step 1

Select Configuration > Remote Access VPN > Load Balancing.

Step 2

Check Participate in Load Balancing to indicate that this ASA is a participant in the load-balancing
cluster
You must enable load balancing in this way on every ASA participating in load balancing.

Step 3

Configure the following fields in the VPN Cluster Configuration area. These values must be the same
for the entire virtual cluster. All servers in the cluster must have an identical cluster configuration.
•

Cluster IPv4 Address—Specifies the single IPv4 address that represents the entire IPv4 virtual
cluster. Choose an IP address that is within the public subnet address range shared by all the ASAs
in the virtual cluster.
– UDP Port—Specifies the UDP port for the virtual cluster in which this device is participating.

The default value is 9023. If another application is using this port, enter the UDP destination
port number you want to use for load balancing.
•

Cluster IPv6 Address—Specifies the single IPv6 address that represents the entire IPv6 virtual
cluster. Choose an IP address that is within the public subnet address range shared by all the ASAs
in the virtual cluster. Clients with IPv6 addresses can make AnyConnect connections through the
ASA cluster’s public-facing IPv6 address or through a GSS server. Likewise, clients with IPv6
addresses can make AnyConnect VPN connections through the ASA cluster’s public-facing IPv4
address or through a GSS server. Either type of connection can be load-balanced within the ASA
cluster.

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Configuring Load Balancing

Step 4

Note

In the Cluster IPv4 Address and Cluster IPv6 Address fields, you can also specify the fully
qualified domain name of the virtual cluster, provided that you have a DNS server group
configured with at least one DNS server, and DNS lookup is enabled on one of the ASA’s
interfaces.

•

Enable IPsec Encryption—Enables or disables IPsec encryption. If you check this box, you must
also specify and verify a shared secret. The ASAs in the virtual cluster communicate via
LAN-to-LAN tunnels using IPsec. To ensure that all load-balancing information communicated
between the devices is encrypted, check this box.

•

IPsec Shared Secret—Specifies the shared secret between IPsec peers when you have enabled
IPsec encryption. The value you enter in the box appears as consecutive asterisk characters.

•

Verify Secret—Re-enter the shared secret. Confirms the shared secret value entered in the IPsec
Shared Secret box.

Configure the fields in the VPN Server Configuration area for a specific ASA:
•

Public Interface—Specifies the name or IP address of the public interface for this device.

•

Private Interface—Specifies the name or IP address of the private interface for this device.

•

Priority—Specifies the priority assigned to this device within the cluster. The range is from 1 to 10.
The priority indicates the likelihood of this device becoming the virtual cluster master, either at
start-up or when an existing master fails. The higher you set the priority (for example, 10), the more
likely this device becomes the virtual cluster master.

Note

If the devices in the virtual cluster are powered up at different times, the first device to be
powered up assumes the role of virtual cluster master. Because every virtual cluster requires a
master, each device in the virtual cluster checks when it is powered-up to ensure that the cluster
has a virtual master. If none exists, that device takes on the role. Devices powered up and added
to the cluster later become backup devices. If all the devices in the virtual cluster are powered
up simultaneously, the device with the highest priority setting becomes the virtual cluster master.
If two or more devices in the virtual cluster are powered up simultaneously, and both have the
highest priority setting, the one with the lowest IP address becomes the virtual cluster master.

•

NAT Assigned IPv4 Address—Specifies the IP address that this device’s IP address is translated to
by NAT. If NAT is not being used (or if the device is not behind a firewall using NAT), leave the field
blank.

•

NAT Assigned IPv6 Address—Specifies the IP address that this device’s IP address is translated to
by NAT. If NAT is not being used (or if the device is not behind a firewall using NAT), leave the field
blank.

•

Send FQDN to client—Check this check box to cause the VPN cluster master to send a fully
qualified domain name using the host and domain name of the cluster device instead of the outside
IP address when redirecting VPN client connections to that cluster device.
By default, the ASA sends only IP addresses in load-balancing redirection to a client. If certificates
are in use that are based on DNS names, the certificates will be invalid when redirected to a backup
device.
As a VPN cluster master, this ASA can send a fully qualified domain name (FQDN), using reverse
DNS lookup, of a cluster device (another ASA in the cluster), instead of its outside IP address, when
redirecting VPN client connections to that cluster device.

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Setting Global NAC Parameters

All of the outside and inside network interfaces on the load-balancing devices in a cluster must be
on the same IP network.

Note

When using IPv6 and sending FQDNS down to client, those names must be resolvable by
the ASA via DNS.

Enable Clientless SSL VPN Load Balancing Using FQDNs
Step 1

Enable the use of FQDNs for Load Balancing by checking the Send FQDN to client instead of an IP
address when redirecting checkbox.

Step 2

Add an entry for each of your ASA outside interfaces into your DNS server, if such entries are not
already present. Each ASA outside IP address should have a DNS entry associated with it for lookups.
These DNS entries must also be enabled for Reverse Lookup.

Step 3

Enable DNS lookups on your ASA on the dialog box Configuration > Device Management > DNS >
DNS Client for whichever interface has a route to your DNS server.

Step 4

Define your DNS server IP address on the ASA. To do this, click Add on this dialog box. This opens the
Add DNS Server Group dialog box. Enter the IPv4 or IPv6 address of the DNS server you want to add;
for example, 192.168.1.1 or 2001:DB8:2000::1.

Step 5

Click OK and Apply.

Setting Global NAC Parameters
The ASA uses Extensible Authentication Protocol (EAP) over UDP (EAPoUDP) messaging to validate
the posture of remote hosts. Posture validation involves checking a remote host for compliancy with
safety requirements before the assignment of a network access policy. An Access Control Server must
be configured for Network Admission Control before you configure NAC on the ASA.
Fields

The NAC pane lets you set attributes that apply to all NAC communications. The following global
attributes at the top of the pane apply to EAPoUDP messaging between the ASA and remote hosts:
•

Port—Port number for EAP over UDP communication with the Cisco Trust Agent (CTA) on the
host. This number must match the port number configured on the CTA. Enter a value in the range
1024 to 65535. The default setting is 21862.

•

Retry if no response—Number of times the ASA resends an EAP over UDP message. This attribute
limits the number of consecutive retries sent in response to Rechallenge Interval expirations. The
setting is in seconds. Enter a value in the range 1 to 3. The default setting is 3.

•

Rechallenge Interval—The ASA starts this timer when it sends an EAPoUDP message to the host.
A response from the host clears the timer. If the timer expires before the ASA receives a response,
it resends the message. The setting is in seconds. Enter a value in the range 1 to 60. The default
setting is 3.

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Configuring Network Admission Control Policies

•

Wait before new PV Session—The ASA starts this timer when it places the NAC session for a remote
host into a hold state. It places a session in a hold state if it does not receive a response after sending
EAPoUDP messages equal to the value of the “Retry if no response” setting. The ASA also starts
this timer after it receives an Access Reject message from the ACS server. When the timer expires,
the ASA tries to initiate a new EAP over UDP association with the remote host. The setting is in
seconds. Enter a value in the range 60 to 86400. The default setting is 180.

The Clientless Authentication area of the NAC pane lets you configure settings for hosts that are not
responsive to the EAPoUDP requests. Hosts for which there is no CTA running do not respond to these
requests.
•

Enable clientless authentication—Click to enable clientless authentication. The ASA sends the
configured clientless username and password to the Access Control Server in the form of a user
authentication request. The ACS in turn requests the access policy for clientless hosts. If you leave
this attribute blank, the ASA applies the default ACL for clientless hosts.

•

Clientless Username—Username configured for clientless hosts on the ACS. The default setting is
clientless. Enter 1 to 64 ASCII characters, excluding leading and trailing spaces, pound signs (#),
question marks (?), single and double quotation marks (“ ” and "), asterisks (*), and angle brackets
(< and >).

•

Password—Password configured for clientless hosts on the ACS. The default setting is clientless.
Enter 4 – 32 ASCII characters.

•

Confirm Password—Password configured for clientless hosts on the ACS repeated for validation.

•

Enable Audit—Click to pass the IP address of the client to an optional audit server if the client does
not respond to a posture validation request. The audit server, such as a Trend server, uses the host
IP address to challenge the host directly to assess its health. For example, it may challenge the host
to determine whether its virus checking software is active and up-to-date. After the audit server
completes its interaction with the remote host, it passes a token to the posture validation server,
indicating the health of the remote host.

•

None—Click to disable clientless authentication and audit services.

Configuring Network Admission Control Policies
The NAC Policies table displays the Network Admission Control (NAC) policies configured on the ASA.
To add, change, or remove a NAC policy, do one of the following:
•

To add a NAC policy, choose Add. The Add NAC Framework Policy dialog box opens.

•

To change a NAC policy, double-click it, or select it and click Edit. The Edit NAC Framework Policy
dialog box opens.

•

To remove a NAC policy, select it and click Delete.

The following sections describe NAC, its requirements, and how to assign values to the policy attributes:
•

About NAC

•

Uses, Requirements, and Limitations

•

Fields

•

What to Do Next

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Configuring Network Admission Control Policies

About NAC
NAC protects the enterprise network from intrusion and infection from worms, viruses, and rogue
applications by performing endpoint compliance and vulnerability checks as a condition for production
access to the network. We refer to these checks as posture validation. You can configure posture
validation to ensure that the anti-virus files, personal firewall rules, or intrusion protection software on
a host with an AnyConnect or Clientless SSL VPN session are up-to-date before providing access to
vulnerable hosts on the intranet. Posture validation can include the verification that the applications
running on the remote hosts are updated with the latest patches. NAC occurs only after user
authentication and the setup of the tunnel. NAC is especially useful for protecting the enterprise network
from hosts that are not subject to automatic network policy enforcement, such as home PCs.
The establishment of a tunnel between the endpoint and the ASA triggers posture validation.
You can configure the ASA to pass the IP address of the client to an optional audit server if the client
does not respond to a posture validation request. The audit server, such as a Trend server, uses the host
IP address to challenge the host directly to assess its health. For example, it may challenge the host to
determine whether its virus checking software is active and up-to-date. After the audit server completes
its interaction with the remote host, it passes a token to the posture validation server, indicating the
health of the remote host.
Following successful posture validation or the reception of a token indicating the remote host is healthy,
the posture validation server sends a network access policy to the ASA for application to the traffic on
the tunnel.
In a NAC Framework configuration involving the ASA, only a Cisco Trust Agent running on the client
can fulfill the role of posture agent, and only a Cisco Access Control Server (ACS) can fulfill the role of
posture validation server. The ACS uses dynamic ACLs to determine the access policy for each client.
As a RADIUS server, the ACS can authenticate the login credentials required to establish a tunnel, in
addition to fulfilling its role as posture validation server.

Note

Only a NAC Framework policy configured on the ASA supports the use of an audit server.
In its role as posture validation server, the ACS uses access control lists. If posture validation succeeds
and the ACS specifies a redirect URL as part of the access policy it sends to the ASA, the ASA redirects
all HTTP and HTTPS requests from the remote host to the redirect URL. Once the posture validation
server uploads an access policy to the ASA, all of the associated traffic must pass both the Security
Appliance and the ACS (or vice versa) to reach its destination.
The establishment of a tunnel between a remote host and the ASA triggers posture validation if a NAC
Framework policy is assigned to the group policy. The NAC Framework policy can, however, identify
operating systems that are exempt from posture validation and specify an optional ACL to filter such
traffic.

Uses, Requirements, and Limitations
When configured to support NAC, the ASA functions as a client of a Cisco Secure Access Control
Server, requiring that you install a minimum of one Access Control Server on the network to provide
NAC authentication services.
Following the configuration of one or more Access Control Servers on the network, you must register
the Access Control Server group, using the Configuration > Remote Access VPN > Clientless SSL
VPN Access > Group Policies > Add or Edit External menu option. Then add the NAC policy.
ASA support for NAC Framework is limited to remote access IPsec and Clientless SSL VPN sessions.
The NAC Framework configuration supports only single mode.

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Configuring Network Admission Control Policies

NAC on the ASA does not support Layer 3 (non-VPN) and IPv6 traffic.
Fields
•

Policy Name—Enter a string of up to 64 characters to name the new NAC policy.
Following the configuration of the NAC policy, the policy name appears next to the NAC Policy
attribute in the Network (Client) Access group policies. Assign a name that will help you to
distinguish its attributes or purpose from others that you may configure.

•

Status Query Period—The ASA starts this timer after each successful posture validation and status
query response. The expiration of this timer triggers a query for changes in the host posture, referred
to as a status query. Enter the number of seconds in the range 30 to 1800. The default setting is 300.

•

Revalidation Period—The ASA starts this timer after each successful posture validation. The
expiration of this timer triggers the next unconditional posture validation. The ASA maintains
posture validation during revalidation. The default group policy becomes effective if the Access
Control Server is unavailable during posture validation or revalidation. Enter the interval in seconds
between each successful posture validation. The range is 300 to 86400. The default setting is 36000.

•

Default ACL— (Optional) The ASA applies the security policy associated with the selected ACL if
posture validation fails. Select None or select an extended ACL in the list. The default setting is
None. If the setting is None and posture validation fails, the ASA applies the default group policy.
Use the Manage button to populate the drop-down list and view the configuration of the ACLs in the
list.

•

Manage— Opens the ACL Manager dialog box. Click to view, enable, disable, and delete standard
ACLs and the ACEs in each ACL. The list next to the Default ACL attribute displays the ACLs.

•

Authentication Server Group—Specifies the authentication server group to use for posture
validation. The drop-down list next to this attribute displays the names of all server groups of type
RADIUS configured on this ASA that are available for remote access tunnels. Select an ACS group
consisting of at least one server configured to support NAC.

•

Posture Validation Exception List—Displays one or more attributes that exempt remote computers
from posture validation. At minimum, each entry lists the operating system and an Enabled setting
of Yes or No. An optional filter identifies an ACL used to match additional attributes of the remote
computer. An entry that consists of an operating system and a filter requires the remote computer to
match both to be exempt from posture validation. The ASA ignores the entry if the Enabled setting
is set to No.

•

Add—Adds an entry to the Posture Validation Exception list.

•

Edit—Modifies an entry in the Posture Validation Exception list.

•

Delete—Removes an entry from the Posture Validation Exception list.

What to Do Next
Following the configuration of the NAC policy, you must assign it to a group policy for it to become
active. To do so, choose Configuration > Remote Access VPN> Network (Client) Access > Group
Policies > Add or Edit > General > More Options and the NAC policy name from the drop-down list
next to the NAC Policy attribute.

Add/Edit Posture Validation Exception
The Add/Edit Posture Validation Exception dialog pane lets you exempt remote computers from posture
validation, based on their operating system and other optional attributes that match a filter.

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Configuring Network Admission Control Policies

•

Operating System—Choose the operating system of the remote computer. If the computer is running
this operating system, it is exempt from posture validation. The default setting is blank.

•

Enable—The ASA checks the remote computer for the attribute settings displayed in this pane only
if you check Enabled. Otherwise, it ignores the attribute settings. The default setting is unchecked.

•

Filter— (Optional) Use to apply an ACL to filter the traffic if the operating system of the computer
matches the value of the Operating System attribute.

•

Manage— Opens the ACL Manager dialog box. Click to view, enable, disable, and delete standard
ACLs and the ACEs in each ACL. The list next to the Default ACL attribute displays the ACLs. Use
this button to populate the list next to the Filter attribute.

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CH AP TE R

4

General VPN Setup
A virtual private network is a network of virtual circuits that carry private traffic over a public network
such as the Internet. VPNs can connect two or more LANS, or remote users to a LAN. VPNs provide
privacy and security by requiring all users to authenticate and by encrypting all data traffic.
•

AnyConnect Customization/Localization, page 4-1

•

Default Tunnel Gateway, page 4-6

•

Group Policies, page 4-7

•

Access Control List Manager, page 4-36

•

Configuring AnyConnect VPN Client Connections, page 4-48

•

Configuring AnyConnect VPN Connections, page 4-57

•

Configuring AnyConnect Secure Mobility, page 4-69

•

IPsec Remote Access Connection Profiles, page 4-78

•

Add or Edit an IPsec Remote Access Connection Profile, page 4-79

•

Mapping Certificates to IPsec or SSL VPN Connection Profiles, page 4-80

•

System Options, page 4-107

•

Zone Labs Integrity Server, page 4-108

•

Easy VPN Remote, page 4-109

•

Advanced Easy VPN Properties, page 4-111

•

AnyConnect Essentials, page 4-113

•

Configuring AnyConnect Host Scan, page 4-115

•

Configuring Maximum VPN Sessions, page 4-122

•

Configuring the Pool of Cryptographic Cores, page 4-122

AnyConnect Customization/Localization
You can customize the AnyConnect VPN client to display your own corporate image to remote users,
including clients running on Windows, Linux, and Mac OS X computers. The following ASDM screens
under AnyConnect Customization/Localization allow you to import the following types of customized
files:
•

Resources—Modified GUI icons for the AnyConnect client.

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AnyConnect Customization/Localization

•

Binary—Executable files to replace the AnyConnect installer. This includes GUI files, plus the
VPN client profile, scripts and other client files.

•

Script—Scripts that will run before or after AnyConnect makes a VPN connection.

•

GUI Text and Messages—Titles and messages used by the AnyConnect client.

•

Customized Installer—Transforms that modify the client installation.

•

Localized Installer—Transforms Transforms that change the language used by the client.

Each dialog provides the following actions:
•

Import launches the Import AnyConnect Customization Objects dialog, where you can specify a
file to import as an object.

•

Export launches the Export AnyConnect Customization Objects dialog, where you can specify a file
to export as an object.

•

Delete removes the selected object.

Restrictions
•

Customization is not supported for the AnyConnect client running on a Windows Mobile device.

AnyConnect Customization/Localization > Resources
The filenames of the custom components that you import must match the filenames used by the
AnyConnect GUI, which are different for each operating system and are case sensitive for Mac and
Linux. For example, if you want to replace the corporate logo for Windows clients, you must import your
corporate logo as company_logo.png. If you import it as a different filename, the AnyConnect installer
does not change the component. However, if you deploy your own executable to customize the GUI, the
executable can call resource files using any filename.
If you import an image as a resource file (such as company_logo.bmp), the image you import customizes
AnyConnect until you reimport another image using the same filename. For example, if you replace
company_logo.bmp with a custom image, and then delete the image, the client continues to display your
image until you import a new image (or the original Cisco logo image) using the same filename.

AnyConnect Customization/Localization > Binary and Script
The same link is used in ASDM for both Binary and Script, so share this link for now, and submit a defect
against ASDM to have them add another link.
AnyConnect Customization/Localization > Binary

For Windows, Linux, or Mac (PowerPC or Intel-based) computers, you can deploy your own client that
uses the AnyConnect client API. You replace the AnyConnect GUI and the AnyConnect CLI by
replacing the client binary files.
Fields for the Import dialog:
•

Name Enter the name of the AnyConnect file that you are replacing.

•

Platform Select the OS platform that your file runs on.

•

Select a file The filename name does not need to be the same as the name of the imported file.

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AnyConnect Customization/Localization

AnyConnect Customization/Localization > Script

For complete information about deploying scripts, and their limitations and restrictions, see the
AnyConnect VPN Client Administrators Guide.
Fields for the Import dialog:
•

Name—Enter a name for the script. Be sure to specify the correct extension with the name. For
example, myscript.bat.

•

Script Type—Choose when to run the script.
AnyConnect adds the prefix scripts_ and the prefix OnConnect or OnDisconnect to your filename
to identify the file as a script on the ASA. When the client connects, the ASA downloads the script
to the proper target directory on the remote computer, removing the scripts_ prefix and leaving the
remaining OnConnect or OnDisconnect prefix. For example, if you import the script myscript.bat,
the script appears on the ASA as scripts_OnConnect_myscript.bat. On the remote computer, the
script appears as OnConnect_myscript.bat.
To ensure the scripts run reliably, configure all ASAs to deploy the same scripts. If you want to
modify or replace a script, use the same name as the previous version and assign the replacement
script to all of the ASAs that the users might connect to. When the user connects, the new script
overwrites the one with the same name.

•

Platform—Select the OS platform that your file runs on.

•

Select a file—The filename name does not need to be the same as the name you provided for the
script.
ASDM imports the file from any source file, creating the new name you specify for Name in Step 3.

AnyConnect Customization/Localization > GUI Text and Messages
You can edit the default translation table, or create new ones, to change the text and messages displayed
on the AnyConnect client GUI . This pane also shares functionality with the Language Localization
pane. For more extensive language translation, go to Configuration > Remote Access VPN > Language
Localization.
In addition to the usual buttons on the top toolbar, this pane also has an Add button, and a Template area
with extra buttons.
Add—The Add button opens a copy of the default translation table, which you can edit directly, or save.
You can select the language of the saved file, and edit the language of the text inside the file later.
When you customize messages in the translation table, do not change msgid, change the text in
msgstr.
Specify a language for the template. The template becomes a translation table in cache memory with
the name you specify. Use an abbreviation that is compatible with the language options for your
browser. For example, if you are creating a table for the Chinese language, and you are using IE, use
the abbreviation zh, that is recognized by IE.
Template Section
•

Click Template to expand the template area, which provides access to the default English translation
table.

•

Click View to view, and optionally save, the default English translation table

•

Click Export to save a copy of the default English translation table without looking at it.

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Client Software

AnyConnect Customization/Localization > Customized Installer Transforms
You can perform more extensive customizing of the AnyConnect client GUI (Windows only) by creating
your own transform that deploys with the client installer program. You import the transform to the ASA,
which deploys it with the installer program.
Windows is the only valid choice for applying a transform. For more information about transforms, see
the AnyConnect Administration Guide.

AnyConnect Customization/Localization > Localized Installer Transforms
You can translate messages displayed by the client installer program with a transform. The transform
alters the installation, but leaves the original security-signed MSI intact. These transforms only translate
the installer screens and do not translate the client GUI screens.

Client Software
Configuration > VPN > General > Client Update
The Client Software pane lets administrators at a central location do the following actions:

Note

•

Enable client update; specify the types and revision numbers of clients to which the update applies.

•

Provide a URL or IP address from which to get the update.

•

In the case of Windows clients, optionally notify users that they should update their VPN client
version.

The Client Update function in Configuration > Remote Access VPN > Network (Client) Access >
Advanced > IPsec > Upload Software > Client Software applies only to the IPsec VPN client, (For
Windows, MAC OS X, and Linux), and the VPN 3002 hardware client. It does not apply to the Cisco
AnyConnect VPN clients, which is updated by the ASA automatically when it connects.
For the IPsec VPN client, you can provide a mechanism for users to accomplish that update. For VPN
3002 hardware client users, the update occurs automatically, with no notification. You can apply client
updates only to the IPsec remote-access tunnel-group type.

Note

If you try to do a client update to an IPsec Site-to-Site IPsec connection or a Clientless VPN IPsec
connection, you do not receive an error message, but no update notification or client update goes to those
types of IPsec connections.
To enable client update globally for all clients of a particular client type, use this dialog box. You can
also notify all Windows, MAC OS X, and Linux clients that an upgrade is needed and initiate an upgrade
on all VPN 3002 hardware clients from this dialog box. To configure the client revisions to which the
update applies and the URL or IP address from which to download the update, click Edit.
To configure client update revisions and software update sources for a specific tunnel group, choose
Configuration > Remote Access VPN > Network (Client) Access > IPsec > Add/Edit > Advanced >
IPsec > Client Software Update.

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Client Software

Fields
•

Enable Client Update—Enables or disables client update, both globally and for specific tunnel
groups. You must enable client update before you can send a client update notification to Windows,
MAC OS X, and Linux VPN clients, or initiate an automatic update to hardware clients.

•

Client Type—Lists the clients to upgrade: software or hardware, and for Windows software clients,
all Windows or a subset. If you click All Windows Based, do not specify Windows 95, 98 or ME and
Windows NT, 2000 or XP individually. The hardware client gets updated with a release of the ASA
5505 software or of the VPN 3002 hardware client.

•

VPN Client Revisions—Contains a comma-separated list of software image revisions appropriate
for this client. If the user client revision number matches one of the specified revision numbers, there
is no need to update the client, and, for Windows-based clients, the user does not receive an update
notification. The following caveats apply:
– The revision list must include the software version for this update.
– Your entries must match exactly those on the URL for the VPN client, or the TFTP server for

the hardware client.
– The TFTP server for distributing the hardware client image must be a robust TFTP server.
– A VPN client user must download an appropriate software version from the listed URL.
– The VPN 3002 hardware client software is automatically updated via TFTP, with no notification

to the user.
•

Image URL—Contains the URL or IP address from which to download the software image. This
URL must point to a file appropriate for this client. For Windows, MAC OS X, and Linux-based
clients, the URL must be in the form: http:// or https://. For hardware clients, the URL must be in
the form tftp://.
– For Windows, MAC OS X, and Linux-based VPN clients: To activate the Launch button on the

VPN Client Notification, the URL must include the protocol HTTP or HTTPS and the server
address of the site that contains the update. The format of the URL is:
http(s)://server_address:port/directory/filename. The server address can be either an IP address
or a hostname if you have configured a DNS server. For example:
http://10.10.99.70/vpnclient-win-4.6.Rel-k9.exe
The directory is optional. You need the port number only if you use ports other than 80 for HTTP
or 443 for HTTPS.
– For the hardware client: The format of the URL is tftp://server_address/directory/filename. The

server address can be either an IP address or a hostname if you have configured a DNS server.
For example:
tftp://10.1.1.1/vpn3002-4.1.Rel-k9.bin
•

Edit—Opens the Edit Client Update Entry dialog box, which lets you configure or change client
update parameters. See Edit Client Update Entry.

•

Live Client Update—Sends an upgrade notification message to all currently connected VPN clients
or selected tunnel group(s).
– Tunnel Group—Selects all or specific tunnel group(s) for updating.
– Update Now—Immediately sends an upgrade notification containing a URL specifying where

to retrieve the updated software to the currently connected VPN clients in the selected tunnel
group or all connected tunnel groups. The message includes the location from which to
download the new version of software. The administrator for that VPN client can then retrieve
the new software version and update the VPN client software.

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Default Tunnel Gateway

For VPN 3002 hardware clients, the upgrade proceeds automatically, with no notification.
You must check Enable Client Update for the upgrade to work. Clients that are not connected
receive the upgrade notification or automatically upgrade the next time they log on.

Edit Client Update Entry
Configuration > VPN > General > Client Update > Edit Client Update Entry
The Edit Client Update dialog box lets you change information about VPN client revisions and URLs
for the indicated client types. The clients must be running one of the revisions specified for the indicated
client type. If not, the clients are notified that an upgrade is required.
Fields
•

Client Type—(Display-only) Displays the client type selected for editing.

•

VPN Client Revisions—Lets you type a comma-separated list of software or firmware images
appropriate for this client. If the user client revision number matches one of the specified revision
numbers, there is no need to update the client. If the client is not running a software version on the
list, an update is in order. The user of a Windows, MAC OS X, or Linux-based VPN client must
download an appropriate software version from the listed URL. The VPN 3002 hardware client
software is automatically updated via TFTP.

•

Image URL—Lets you type the URL for the software/firmware image. This URL must point to a
file appropriate for this client.
– For a Windows, MAC OS X, or Linux-based VPN client, the URL must include the protocol

HTTP or HTTPS and the server address of the site that contains the update. The format of the
URL is: http(s)://server_address:port/directory/filename. The server address can be either an IP
address or a hostname if you have configured a DNS server. For example:
http://10.10.99.70/vpnclient-win-4.6.Rel-k9.exe

The directory is optional. You need the port number only if you use ports other than 80 for HTTP
or 443 for HTTPS.
– For the hardware client: The format of the URL is tftp://server_address/directory/filename. The

server address can be either an IP address or a hostname if you have configured a DNS server.
For example:
tftp://10.1.1.1/vpn3002-4.1.Rel-k9.bin
The directory is optional.

Default Tunnel Gateway
Configuration > VPN > General > Default Tunnel Gateway
To configure the default tunnel gateway, click the Static Route link. The Configuration > Routing >
Routing > Static Route dialog box opens.

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Group Policies

Group Policies
The Group Policies pane lets you manage VPN (AnyConnect or Clientless) group policies. A VPN group
policy is a collection of user-oriented attribute/value pairs stored either internally on the device or
externally on a RADIUS or LDAP server. Configuring the VPN group policy lets users inherit attributes
that you have not configured at the individual group or username level. By default, VPN users have no
group policy association. The group policy information is used by VPN tunnel groups and user accounts.
The “child” panes and dialog boxes let you configure the group parameters, including those for the
default group, DfltGrpPolicy. The default group parameters are those that are most likely to be common
across all groups and users, and they streamline the configuration task. Groups can “inherit” parameters
from this default group, and users can “inherit” parameters from their group or the default group. You
can override these parameters as you configure groups and users.
You can configure either an internal or an external group policy. An internal group policy is stored
locally, and an external group policy is stored externally on a RADIUS or LDAP server. Clicking Edit
opens a similar dialog box on which you can create a new group policy or modify an existing one.
In these dialog boxes, you configure the following kinds of parameters:
•

General attributes: Name, banner, address pools, protocols, filtering, and connection settings.

•

Servers: DNS and WINS servers, DHCP scope, and default domain name.

•

Advanced attributes: Split tunneling, IE browser proxy, AnyConnect client, and IPsec client.

Before configuring these parameters, you should configure:
• Access hours.
•

Filters.

•

Network lists for filtering and split tunneling

•

User authentication servers and the internal authentication server.

You can configure these types of group policies:
•

Configuring External Group Policies—An external group policy points the ASA to the RADIUS or
LDAP server to retrieve much of the policy information that would otherwise be configured in an
internal group policy. External group policies are configured the same way for Network (Client)
Access VPN connections, Clientless SSL VPN connections, and Site-to-Site VPN connections.

•

Configuring Network (Client) Access Internal Group Policies—These connections are initiated by
a VPN client installed on the endpoint. The AnyConnect Secure Mobility Client and Cisco VPN
IPsec client are examples of VPN clients. After the VPN client is authenticated, remote users can
access corporate networks or applications as if they were on-site. The data traffic between remote
users and the corporate network is secured by being encrypted when going through the Internet.

•

Configuring Clientless SSL VPN Internal Group Policies—This is also known as browser-based
VPN access. On successful login to the ASA’s portal page, remote users can access corporate
networks and applications from the links shown in the web pages. The data traffic between remote
users and the corporate network is secured by traveling through SSL tunnel.

•

Configuring Site-to-Site Internal Group Policies

Group Policy Pane Fields

Lists the currently configured group policies and Add, Edit, and Delete buttons to help you manage VPN
group policies.

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Group Policies

•

Add—Offers a drop-down menu on which you can select whether to add an internal or an external
group policy. If you simply click Add, then by default, you create an internal group policy. Clicking
Add opens the Add Internal Group Policy dialog box or the Add External Group Policy dialog box,
which let you add a new group policy to the list. This dialog box includes three menu sections. Click
each menu item to display its parameters. As you move from item to item, ASDM retains your
settings. When you have finished setting parameters on all menu sections, click Apply or Cancel.
Offers a drop-down menu from which you can select whether to add an internal or an external group
policy. If you simply click Add, then by default, you create an internal group policy.

•

Edit—Displays the Edit Group Policy dialog box, which lets you modify an existing group policy.

•

Delete—Lets you remove a AAA group policy from the list. There is no confirmation or undo.

•

Assign—Lets you assign a group policy to one ore more connection profiles.

•

Name—Lists the name of the currently configured group policies.

•

Type—Lists the type of each currently configured group policy.

•

Tunneling Protocol—Lists the tunneling protocol that each currently configured group policy uses.

•

Connection Profiles/Users Assigned to—Lists the connection profiles and users configured directly
on the ASA that are associated with this group policy.

Configuring External Group Policies
An external group policy points the ASA to the RADIUS or LDAP server to retrieve much of the policy
information that would otherwise be configured in an internal group policy. External group policies are
configured the same way for Network (Client) Access VPN connections, Clientless SSL VPN
connections, and Site-to-Site VPN connections.
External group policies take their attribute values from the external server that you specify. For an
external group policy, you must identify the RADIUS or LDAP server group that the ASA can query for
attributes and specify the password to use when retrieving attributes from that external server group. If
you are using an external authentication server, and if your external group-policy attributes exist in the
same RADIUS server as the users that you plan to authenticate, you have to make sure that there is no
name duplication between them.

Note

External group names on the ASA refer to user names on the RADIUS server. In other words, if you
configure external group X on the ASA, the RADIUS server sees the query as an authentication request
for user X. So external groups are really just user accounts on the RADIUS server that have special
meaning to the ASA. If your external group attributes exist in the same RADIUS server as the users that
you plan to authenticate, there must be no name duplication between them.
The ASA supports user authorization on an external LDAP or RADIUS server. Before you configure the
ASA to use an external server, you must configure the server with the correct ASA authorization
attributes and, from a subset of these attributes, assign specific permissions to individual users. Follow
the instructions in Appendix 13, “Configuring an External Server for Authorization and Authentication”
to configure your external server.
Fields
•

Name—Identifies the group policy to be added or changed. For Edit External Group Policy, this field
is display-only.

•

Server Group—Lists the available server groups to which to apply this policy.

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Group Policies

•

New—Opens a dialog box that lets you select whether to create a new RADIUS server group or a
new LDAP server group. Either of these options opens the Add AAA Server Group dialog box.

•

Password—Specifies the password for this server group policy.

Adding an LDAP or RADIUS Server to a Network (Client) Access External Group Policy
Configuration > Remote Access VPN > Network (Client) Access > Group Policies > Add/Edit >
Add or Edit External Group Policy > New > RADIUS Server Group/New LDAP Server Group >
Add AAA Server Group
The Add AAA Server Group dialog box lets you configure a new AAA server group. The Accounting
Mode attribute applies only to RADIUS and TACACS+ protocols.
Fields
•

Server Group—Specifies the name of the server group.

•

Protocol—(Display only) Indicates whether this is a RADIUS or an LDAP server group.

•

Accounting Mode—Indicates whether to use simultaneous or single accounting mode. In single
mode, the ASA sends accounting data to only one server. In simultaneous mode, the ASA sends
accounting data to all servers in the group. The Accounting Mode attribute applies only to RADIUS
and TACACS+ protocols.

•

Reactivation Mode—Specifies the method by which failed servers are reactivated: Depletion or
Timed reactivation mode. In Depletion mode, failed servers are reactivated only after all of the
servers in the group become inactive. In Timed mode, failed servers are reactivated after 30 seconds
of down time.

•

Dead Time—Specifies, for depletion mode, the number of minutes (0 through 1440) that must elapse
between the disabling of the last server in the group and the subsequent re-enabling of all servers.
The default value is 10 minutes. This field is not available for timed mode.

•

Max Failed Attempts— Specifies the number (an integer in the range 1 through 5) of failed
connection attempts allowed before declaring a nonresponsive server inactive. The default value is
3 attempts.

Configuring Network (Client) Access Internal Group Policies
Configure Network (Client) Access internal group policies for VPN connections made from AnyConnect
Secure Mobility Clients or legacy Cisco IPsec VPN clients installed on an endpoint.

Configuring General Attributes for an Internal Group Policy
The Add or Edit Group Policy dialog box lets you specify tunneling protocols, filters, connection
settings, and servers for the group policy being added or modified. For each of the fields on this dialog
box, checking the Inherit check box lets the corresponding setting take its value from the default group
policy. Inherit is the default value for all of the attributes in this dialog box.
You can configure the general attributes of an internal group policy by starting ASDM and selecting
Configuration > Remote Access VPN > Network (Client) Access > Group Policies > Add or Edit
Internal Group Policy > General.

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Group Policies

Fields

The following attributes appear in the Add Internal Group Policy > General dialog box. They apply to
SSL VPN and IPsec sessions. Thus, some attributes are present for one type of session, but not the other.
•

Name—Specifies the name of this group policy up to 64 characters; spaces are allowed. For the Edit
function, this field is read-only.

•

Banner—Specifies the banner text to present to users at login. The length can be up to 491
characters. There is no default value.
The IPsec VPN client supports full HTML for the banner. However, the clientless portal and the
AnyConnect client support partial HTML. To ensure the banner displays properly to remote users,
follow these guidelines:
– For IPsec client users, use the /n tag.
– For AnyConnect client users, use the 
tag. • SCEP forwarding URL—Address of the CA, required when SCEP Proxy is configured in the client profile. • Address Pools—Specifies the name of one or more IPv4 address pools to use for this group policy. If the Inherit check box is checked, the group policy will use the IPv4 address pool specified in the Default Group Policy. See Configuring Local IP Address Pools, page 5-3 for information on adding or editing an IPv4 address pool. Select—Uncheck the Inherit checkbox to activate the Select command button. Click Select to open the Address Pools dialog box, which shows the pool name, starting and ending addresses, and subnet mask of address pools available for client address assignment and lets you select, add, edit, delete, and assign entries from that list. • IPv6 Address Pools—Specifies the name of one or more IPv6 address pools to use for this group policy. Select—Uncheck the Inherit checkbox to activate the Select command button. Click Select to open the Select Address Pools dialog box, as previously described. See Configuring Local IP Address Pools, page 5-3 for information on adding or editing an IPv6 address pool. Note You can specify both an IPv4 and an IPv6 address pool for an internal group policy. • More Options—Click the down arrows at the right of the field to display additional configurable options for this group policy. • Tunneling Protocols—Specifies the tunneling protocols that this group can use. Users can use only the selected protocols. The choices are as follows: – Clientless SSL VPN—Specifies the use of VPN via SSL/TLS, which uses a web browser to establish a secure remote-access tunnel to an ASA; requires neither a software nor hardware client. Clientless SSL VPN can provide easy access to a broad range of enterprise resources, including corporate websites, web-enabled applications, NT/AD file share (web-enabled), e-mail, and other TCP-based applications from almost any computer that can reach HTTPS Internet sites. – SSL VPN Client—Specifies the use of the Cisco AnyConnect VPN client or the legacy SSL VPN client. If you are using the AnyConnect client, you must choose this protocol for Mobile User Security (MUS) to be supported. – IPsec IKEv1—IP Security Protocol. Regarded as the most secure protocol, IPsec provides the most complete architecture for VPN tunnels. Both Site-to-Site (peer-to-peer) connections and Cisco VPN client-to-LAN connections can use IPsec IKEv1. Cisco ASA Series VPN ASDM Configuration Guide 4-10 Chapter 4 General VPN Setup Group Policies – IPsec IKEv2—Supported by the AnyConnect Secure Mobility Client. AnyConnect connections using IPsec with IKEv2 provide advanced features such as software updates, client profiles, GUI localization (translation) and customization, Cisco Secure Desktop, and SCEP proxy. – L2TP over IPsec—Allows remote users with VPN clients provided with several common PC and mobile PC operating systems to establish secure connections over the public IP network to the security appliance and private corporate networks. L2TP uses PPP over UDP (port 1701) to tunnel the data. The security appliance must be configured for IPsec transport mode. • Filter—Specifies which unified access control list to use for an IPv4 or an IPv6 connection, or whether to inherit the value from the group policy. Filters consist of rules that determine whether to allow or reject tunneled data packets coming through the ASA, based on criteria such as source address, destination address, and protocol. To configure filters and rules, see the ACL Manager dialog box. Manage—Displays the ACL Manager dialog box, with which you can add, edit, and delete Access Control Lists (ACLs) and Extended Access Control Lists (ACEs). For more information about the ACL Manager, see the online Help for that dialog box. • NAC Policy—Selects the name of a Network Admission Control policy to apply to this group policy. You can assign an optional NAC policy to each group policy. The default value is --None--. • Manage—Opens the Configure NAC Policy dialog box. After configuring one or more NAC policies, the NAC policy names appear as options in the drop-down list next to the NAC Policy attribute. • Access Hours—Selects the name of an existing access hours policy, if any, applied to this user or create a new access hours policy. The default value is Inherit, or, if the Inherit check box is not checked, the default value is --Unrestricted--. Manage—Opens the Browse Time Range dialog box, in which you can add, edit, or delete a time range. See Defining Time Ranges, page 4-35 for more information. • Simultaneous Logins—Specifies the maximum number of simultaneous logins allowed for this user. The default value is 3. The minimum value is 0, which disables login and prevents user access. Note • Note While there is no maximum limit, allowing several simultaneous connections might compromise security and affect performance. Restrict Access to VLAN—(Optional) Also called “VLAN mapping,” this parameter specifies the egress VLAN interface for sessions to which this group policy applies. The ASA forwards all traffic from this group to the selected VLAN. Use this attribute to assign a VLAN to the group policy to simplify access control. Assigning a value to this attribute is an alternative to using ACLs to filter traffic on a session. In addition to the default value (Unrestricted), the drop-down list shows only the VLANs that are configured on this ASA. This feature works for HTTP connections, but not for FTP and CIFS. • Connection Profile (Tunnel Group) Lock—This parameter permits remote VPN access only with the selected connection profile (tunnel group), and prevents access with a different connection profile. The default inherited value is None. • Maximum Connect Time—If the Inherit check box is not checked, this parameter specifies the maximum user connection time in minutes. At the end of this time, the system terminates the connection. The minimum is 1 minute, and the maximum is 35791394 minutes (over 4000 years, should we be so lucky). To allow unlimited connection time, check Unlimited (the default). Cisco ASA Series VPN ASDM Configuration Guide 4-11 Chapter 4 General VPN Setup Group Policies • Idle Timeout—If the Inherit check box is not checked, this parameter specifies this user’s idle timeout period in minutes. If there is no communication activity on the user connection in this period, the system terminates the connection. The minimum time is 1 minute, and the maximum time is 10080 minutes. The default is 30 minutes. To allow unlimited connection time, check Unlimited. This value does not apply to Clientless SSL VPN users. • On smart card removal—With the default option, Disconnect, the client tears down the connection if the smart card used for authentication is removed. Click Keep the connection if you do not want to require users to keep their smart cards in the computer for the duration of the connection. Smart card removal configuration only works on Microsoft Windows using RSA smart cards. Configuring Server Attributes for an Internal Group Policy Configure DNS servers, WINS servers and DHCP Scope in the Group Policy > Servers window. DNS and WINS servers are applied to full-tunnel clients (IPsec, AnyConnect, SVC, L2TP/IPsec) only and are used for name resolution. DHCP scope is used when DHCP-address assignment is in place. Configuring a DNS Server for an Internal Group Policy Use this procedure to configure a specific DNS server for a group policy. Note This setting overrides the DNS setting configured on the ASDM in the Configuration > Remote Access VPN > DNS window. Step 1 Select Configuration > Remote Access VPN > Network (Client) Access > Group Policies > Add/Edit > Servers. Step 2 Unless you are editing the DefaultGroupPolicy, uncheck the DNS Servers Inherit checkbox. Step 3 In the DNS Servers field, add the IPv4 or IPv6 addresses of the DNS servers you want this group to use. If you specify more than one DNS server, the remote access client will attempt to use the DNS servers in the order you specify them in this field. AnyConnect 3.0.4 and later supports up to 25 DNS server entries in the DNS Servers field, earlier releases only support up to 10 DNS server entries. Step 4 Expand the More Options area by clicking the double down arrow in the More Options bar. Step 5 If there is no default domain specified in the Configuration > Remote Access VPN > DNS window, you must specify the default domain in the Default Domain field. Use the domain name and top level domain for example, example.com. Step 6 Click OK. Step 7 Click Apply. Configuring WINS Servers for an Internal Group Policy Use this procedure to configure primary and secondary WINS servers. WINS servers are applied to full-tunnel clients (IPsec, AnyConnect, SVC, L2TP/IPsec) only and are used for name resolution. The default value in each case is none. Cisco ASA Series VPN ASDM Configuration Guide 4-12 Chapter 4 General VPN Setup Group Policies Step 1 Select Configuration > Remote Access VPN > Network (Client) Access > Group Policies > Add/Edit > Servers. Step 2 Uncheck the WINS Servers Inherit checkbox. Step 3 In the WINS Servers field, enter the IP addresses of the primary and secondary WINS servers. The first IP address you specify is that of the primary WINS server. The second (optional) IP address you specify is that of the secondary WINS server. Step 4 Click OK. Configuring Split Tunneling for AnyConnect Traffic Split tunneling directs some of the AnyConnect network traffic through the VPN tunnel (encrypted) and other network traffic outside the VPN tunnel (unencrypted or “in the clear”). Split tunneling is configured by creating a split tunneling policy, configuring an access control list for that policy, and adding the split tunnel policy to a group policy. When the group policy is sent to the client, that client will use the ACLs in the split tunneling policy to decide where to direct network traffic. For Windows clients, firewall rules from the ASA are evaluated first, then the ones on the client. For Mac OS X, the firewall and filter rules on the client are not used. For Linux systems, starting with AnyConnect version 3.1.05149, you can configure AnyConnect to evaluate the client's firewall and filter rules, by adding a custom attribute named circumvent-host-filtering to a group profile, and setting it to true. When you create access lists: • You can specify both IPv4 and IPv6 addresses in an access control list. • If you use a standard ACL, only one address or network is used. • If you use extended ACLs, the source network is the split-tunneling network. The destination network is ignored. • Access lists configured with any or with a split include or exclude of 0.0.0.0/0.0.0.0 or ::/0 will not be sent to the client. To send all traffic over the tunnel, select Tunnel All Networks for the split-tunnel Policy. • Address 0.0.0.0/255.255.255.255 or ::/128 will be sent to the client only when the split-tunnel policy is Exclude Network List Below. This configuration tells the client not to tunnel traffic destined for any local subnets. • AnyConnect passes traffic to all sites specified in the split tunneling policy, and to all sites that fall within the same subnet as the IP address assigned by the ASA. For example, if the IP address assigned by the ASA is 10.1.1.1 with a mask of 255.0.0.0, the endpoint device passes all traffic destined to 10.0.0.0/8, regardless of the split tunneling policy. Therefore, use a netmask for the assigned IP address that properly references the expected local subnet. Prerequisites • You must create an access list with ACLs and (optionally) ACEs. • If you created a split tunnel policy for IPv4 networks and another for IPv6 networks, then the network list you specify is used for both protocols. So, the network list should contain access control entries (ACEs) for both IPv4 and IPv6 traffic. If you have not created these ACLs, see the “Adding ACLs and ACEs” section on page 21-2 in the general operations configuration guide. Cisco ASA Series VPN ASDM Configuration Guide 4-13 Chapter 4 General VPN Setup Group Policies Note Split tunneling is a traffic management feature, not a security feature. For optimum security, we recommend that you do not enable split tunneling. In the following procedure, in all cases where there is an Inherit checkbox next to a field, leaving the Inherit check box checked means that the group policy you are configuring will use the same values for that field as the default group policy. Unchecking Inherit lets you specify new values specific to your group policy. Step 1 Connect to the ASA using ASDM and select Configuration > Remote Access VPN > Network (Client) Access > Group Policies. Step 2 Click Add to add a new group policy or select an existing group policy and click Edit. Step 3 Select Advanced > Split Tunneling. Step 4 In the DNS Names field, enter the domain names that are to be resolved by AnyConnect via the tunnel. These names correspond to hosts in the private network. If split-include tunneling is configured, the network list must include the specified DNS servers. You can enter a full qualified domain name, IPv4 or IPv6 address in the field. Step 5 To disable split tunneling, select Yes for Send All DNS Lookups Through Tunnel. This option ensures that DNS traffic is not leaked to the physical adapter; it disallows traffic in the clear. If DNS resolution fails, the address remains unresolved and the AnyConnect client does not try to resolve the address outside the VPN. To enable split tunneling, choose No (the default). This setting tells the client send DNS queries over the tunnel according to the split tunnel policy. Step 6 To configure split-tunneling by unchecking the Inherit check box and choosing a split-tunneling policy. If you do not uncheck Inherit, your group policy uses the split tunneling settings defined in the default group policy, DfltGrpPolicy. The default split tunneling policy setting in the default group policy is to Tunnel All Networks. To define the split tunneling policy, chose from the drop-downs Policy and IPv6 Policy. The Policy field defines the split tunneling policy for IPv4 network traffic. The IPv6 Policy field selects the split tunneling policy for IPv6 network traffic. Other than that difference, these fields have the same purpose. Unchecking Inherit allows you to choose one of these policy options: • Exclude Network List Below—Defines a list of networks to which traffic is sent in the clear. This feature is useful for remote users who want to access devices on their local network, such as printers, while they are connected to the corporate network through a tunnel. • Tunnel Network List Below—Tunnels all traffic from or to the networks specified in the Network List. Traffic to addresses in the include network list are tunneled. Data to all other addresses travels in the clear and is routed by the remote user’s Internet service provider. For versions of ASA 9.1.4 and higher, when you specify an include list, you can also specify an exclude list that is a subnet inside the include range. Those excluded subnets will not be tunneled, and the rest of the include list networks will be. Networks in the exclusion list that are not a subset of the include list will be ignored by the client. For Linux, you must add a custom attribute to the group policy to support excluded subnets. For example: Cisco ASA Series VPN ASDM Configuration Guide 4-14 Chapter 4 General VPN Setup Group Policies Note If the split-include network is an exact match of a local subnet (such as 192.168.1.0/24), the corresponding traffic is tunneled. If the split-include network is a superset of a local subnet (such as 192.168.0.0/16), the corresponding traffic, except the local subnet traffic, is tunneled. To also tunnel the local subnet traffic, you must add a matching split-include network(specifying both 192.168.1.0/24 and 192.168.0.0/16 as split-include networks). If the split-include network is invalid, such as 0.0.0.0/0.0.0.0, then split tunneling is disabled (everything is tunneled). • Step 7 Tunnel All Networks—This policy specifies that all traffic is tunneled. This, in effect, disables split tunneling. Remote users reach Internet networks through the corporate network and do not have access to local networks. This is the default option. In the Network List field, select the access control list for the split-tunneling policy. If Inherit is checked, the group policy uses the network list specified in the default group policy. Select the Manage command button to open the ACL Manager dialog box, in which you can configure access control lists to use as network lists. For more information about how to create or edit a network list, see the “Adding ACLs and ACEs” section on page 21-2 in the general operations configuration guide. Extended ACL lists can contain both IPv4 and IPv6 addresses. Step 8 Step 9 The Intercept DHCP Configuration Message from Microsoft Clients reveals additional parameters specific to DHCP Intercept. DHCP Intercept lets Microsoft XP clients use split-tunneling with the ASA. • Intercept—Specifies whether to allow the DHCP Intercept to occur. If you do not select, Inherit, the default setting is No. • Subnet Mask—Selects the subnet mask to use. Click OK. Configure Linux to Support Excluded Subnets When Tunnel Network List Below is configured for split tunneling, Linux requires extra configuration to support exclude subnets. You must create a custom attribute named circumvent-host-filtering, set it to true, and associate with the group policy that is configured for split tunneling. The following steps describe how to create the custom attribute. Step 1 Connect to the ASDM, and select Configuration > Remote Access VPN > Network (Client) Access > Advanced > AnyConnect Custom Attributes. Cisco ASA Series VPN ASDM Configuration Guide 4-15 Chapter 4 General VPN Setup Group Policies Step 2 Click Add, create a custom attribute named circumvent-host-filtering, and set the value to true. Step 3 Edit the group policy you plan to use for client firewall, and select Advanced > AnyConnect Client > Custom Attributes. Step 4 Add the custom attribute that you created, circumvent-host-filtering, to the group policy you will use for split tunneling. Configuring VPN Policy Attributes for a Local User To configure VPN policy attributes for a user, perform the following steps: Detailed Steps Step 1 Start ASDM and choose Configuration > Remote Access VPN > AAA/Local Users > Local Users. Step 2 Select the user you want to configure and click Edit. The Edit User Account dialog box appears. Step 3 In the left-hand pane, click VPN Policy. Step 4 Specify a group policy for the user. The user policy will inherit the attributes of this group policy. If there are other fields that are set to inherit the configuration from the Default Group Policy, the attributes specified in this group policy will take precedence over those set in the Default Group Policy. Step 5 Specify which tunneling protocols are available for the user, or whether the value is inherited from the group policy. Check the desired Tunneling Protocols check boxes to choose the VPN tunneling protocols that you want to make available for use. The choices are as follows: • Clientless SSL VPN (VPN via SSL/TLS) uses a web browser to establish a secure remote-access tunnel to a VPN concentrator; this option requires neither a software nor hardware client. Clientless SSL VPN can provide easy access to a broad range of enterprise resources, including corporate websites, web-enabled applications, web-enabled NT/AD file shares, e-mail, and other TCP-based applications from almost any computer that can reach secure Internet sites through HTTPS. • The SSL VPN Client lets you connect after downloading the Cisco AnyConnect Client application. You use a clientless SSL VPN connection to download this application the first time. Client updates then occur automatically as needed whenever you connect. • IPsec IKEv1—IP Security Protocol. Regarded as the most secure protocol, IPsec provides the most complete architecture for VPN tunnels. Both site-to-site (peer-to-peer) connections and Cisco VPN client-to-LAN connections can use IPsec IKEv1. • IPsec IKEv2—Supported by the AnyConnect Secure Mobility Client. AnyConnect connections using IPsec with IKEv2 provide advanced features such as software updates, client profiles, GUI localization (translation) and customization, Cisco Secure Desktop, and SCEP proxy. • L2TP over IPsec allows remote users with VPN clients provided with several common PC and mobile PC operating systems to establish secure connections over the public IP network to the ASA and private corporate networks. Note If no protocol is selected, an error message appears. Cisco ASA Series VPN ASDM Configuration Guide 4-16 Chapter 4 General VPN Setup Group Policies Step 6 Specify which filter (IPv4 or IPv6) to use, or whether to inherit the value from the group policy. Filters consist of rules that determine whether to allow or reject tunneled data packets coming through the ASA, based on criteria such as source address, destination address, and protocol. To configure filters and rules, choose Configuration > Remote Access VPN > Network (Client) Access > Group Policies > Add/Edit > General > More Options > Filter. Click Manage to display the ACL Manager pane, on which you can add, edit, and delete ACLs and ACEs. Step 7 Specify whether to inherit the Connection Profile (tunnel group) lock or to use the selected tunnel group lock, if any. Selecting a specific lock restricts users to remote access through this group only. Tunnel group lock restricts users by checking to see if the group configured in the VPN client is the same as the users assigned group. If it is not, the ASA prevents the user from connecting. If the Inherit check box is not checked, the default value is None. Step 8 Specify whether to inherit the Store Password on Client System setting from the group. Uncheck the Inherit check box to activate the Yes and No radio buttons. Click Yes to store the login password on the client system (potentially a less-secure option). Click No (the default) to require the user to enter the password with each connection. For maximum security, we recommend that you not allow password storage. Step 9 Specify an Access Hours policy to apply to this user, create a new access hours policy for the user, or leave the Inherit box checked. The default value is Inherit, or, if the Inherit check box is not checked, the default value is Unrestricted. Click Manage to open the Add Time Range dialog box, in which you can specify a new set of access hours. Step 10 Specify the number of simultaneous logins by the user. The simultaneous logins setting specifies the maximum number of simultaneous logins allowed for this user. The default value is 3. The minimum value is 0, which disables login and prevents user access. Note While there is no maximum limit, allowing several simultaneous connections could compromise security and affect performance. Step 11 Specify the maximum connection time for the user connection time in minutes. At the end of this time, the system terminates the connection. The minimum is 1 minute, and the maximum is 2147483647 minutes (over 4000 years). To allow unlimited connection time, check the Unlimited check box (the default). Step 12 Specify the idle timeout for the user in minutes. If there is no communication activity on the connection by this user in this period, the system terminates the connection. The minimum time is 1 minute, and the maximum time is 10080 minutes. This value does not apply to users of clientless SSL VPN connections. Step 13 Configure the session alert interval. If you uncheck the Inherit check box, the Default check box is checked automatically and the session alert interval is set to 30 minutes. If you want to specify a new value, uncheck the Default check box and specify a session alert interval from 1 to 30 minutes in the minutes box. Step 14 Configure the idle alert interval. If you uncheck the Inherit check box, the Default check box is checked automatically. This sets the idle alert interval to 30 minutes. If you want to specify a new value, uncheck the Default check box and specify a session alert interval from 1 to 30 minutes in the minutes box. Step 15 To set a dedicated IPv4 address for this user, enter an IPv4 address and subnet mask in the Dedicated IPv4 Address (Optional) area. Step 16 To set a dedicated IPv6 address for this user, enter an IPv6 address with an IPv6 prefix in the Dedicated IPv6 Address (Optional) field. The IPv6 prefix indicates the subnet on which the IPv6 address resides. Cisco ASA Series VPN ASDM Configuration Guide 4-17 Chapter 4 General VPN Setup Group Policies Step 17 Click OK. The changes are saved to the running configuration. Configuring a Browser Proxy for an Internal Group Policy Configuration > Remote Access VPN > Network (Client) Access > Group Policies > Add/Edit > Advanced > Browser Proxy This dialog box configures attributes for Microsoft Internet Explorer. Fields • Proxy Server Policy—Configures the Microsoft Internet Explorer browser proxy actions (“methods”) for a client PC. – Do not modify client proxy settings—Leaves the HTTP browser proxy server setting in Internet Explorer unchanged for this client PC. – Do not use proxy—Disables the HTTP proxy setting in Internet Explorer for the client PC. – Select proxy server settings from the following—Enables the following check boxes for your selections: Auto detect proxy, Use proxy server settings given below, and Use proxy auto configuration (PAC) given below. – Auto detect proxy—Enables the use of automatic proxy server detection in Internet Explorer for the client PC. – Use proxy server settings specified below—Sets the HTTP proxy server setting in Internet Explorer to use the value configured in the Proxy Server Name or IP Address field. – Use proxy auto configuration (PAC) given below—Specifies the use of the file specified in the Proxy Auto Configuration (PAC) field as the source for auto configuration attributes. • Proxy Server Settings—Configures the proxy server parameters for Microsoft clients using Microsoft Internet Explorer. – Server Address and Port—Specifies the IP address or name and the port of an Microsoft Internet Explorer server that is applied for this client PC. – Bypass Proxy Server for Local Addresses—Configures Microsoft Internet Explorer browser proxy local-bypass settings for a client PC. Click Yes to enable local bypass or No to disable local bypass. – Exception List—Lists the server names and IP addresses that you want to exclude from proxy server access. Enter the list of addresses that you do not want to have accessed through a proxy server. This list corresponds to the Exceptions list in the Proxy Settings dialog box in Internet Explorer. • Proxy Auto Configuration Settings—The PAC URL specifies the URL of the auto-configuration file. This file tells the browser where to look for proxy information. To use the proxy auto-configuration (PAC) feature, the remote user must use the Cisco AnyConnect VPN client. Many network environments define HTTP proxies that connect a web browser to a particular network resource. The HTTP traffic can reach the network resource only if the proxy is specified in the browser and the client routes the HTTP traffic to the proxy. SSLVPN tunnels complicate the definition of HTTP proxies because the proxy required when tunneled to an enterprise network can differ from that required when connected to the Internet via a broadband connection or when on a third-party network. Cisco ASA Series VPN ASDM Configuration Guide 4-18 Chapter 4 General VPN Setup Group Policies In addition, companies with large networks might need to configure more than one proxy server and let users choose between them, based on transient conditions. By using .pac files, an administrator can author a single script file that determines which of numerous proxies to use for all client computers throughout the enterprise. The following are some examples of how you might use a PAC file: – Choosing a proxy at random from a list for load balancing. – Rotating proxies by time of day or day of the week to accommodate a server maintenance schedule. – Specifying a backup proxy server to use in case the primary proxy fails. – Specifying the nearest proxy for roaming users, based on the local subnet. You can use a text editor to create a proxy auto-configuration (.pac) file for your browser. A .pac file is a JavaScript file that contains logic that specifies one or more proxy servers to be used, depending on the contents of the URL. Use the PAC URL field to specify the URL from which to retrieve the .pac file. Then the browser uses the .pac file to determine the proxy settings. Configuring General AnyConnect Client Attributes for an Internal Group Policy Clicking the AnyConnect Client icon in the group policy directory tree shows the list of configurable attributes that follow. Configuring the ASA to distribute and manage AnyConnect client sessions is a larger procedure than just setting these attribute fields in a group policy. See Configuring AnyConnect VPN Client Connections, page 4-48, Configuring AnyConnect VPN Connections, page 4-57, and Configuring AnyConnect Secure Mobility, page 4-69. Fields • Keep Installer on Client System—Enable permanent client installation on the remote computer. Enabling disables the automatic uninstalling feature of the client. The client remains installed on the remote computer for subsequent connections, reducing the connection time for the remote user. Note Keep Installer on Client System is not supported after version 2.5 of the AnyConnect client. • Datagram Transport Layer Security (DTLS)—Avoids latency and bandwidth problems associated with some SSL connections and improves the performance of real-time applications that are sensitive to packet delays. • Ignore Don’t Defrag (DF) Bit—This feature allows the force fragmentation of packets that have the DF bit set, allowing them to pass through the tunnel. An example use case is for servers in your network that do not respond correctly to TCP MSS negotiations. • Client Bypass Protocol—The Client Protocol Bypass feature allows you to configure how the ASA manages IPv4 traffic when it is expecting only IPv6 traffic or how it manages IPv6 traffic when it is expecting only IPv4 traffic. When the AnyConnect client makes a VPN connection to the ASA, the ASA could assign it an IPv4, IPv6, or both an IPv4 and IPv6 address. If the ASA assigns the AnyConnect connection only an IPv4 address or only an IPv6 address, you can now configure the Client Bypass Protocol to drop network traffic for which the ASA did not assign an IP address, or allow that traffic to bypass the ASA and be sent from the client unencrypted or “in the clear”. Cisco ASA Series VPN ASDM Configuration Guide 4-19 Chapter 4 General VPN Setup Group Policies For example, assume that the ASA assigns only an IPv4 address to an AnyConnect connection and the endpoint is dual stacked. When the endpoint attempts to reach an IPv6 address, if Client Bypass Protocol is disabled, the IPv6 traffic is dropped; however, if Client Bypass Protocol is enabled, the IPv6 traffic is sent from the client in the clear. • FQDN of This Device—This information is used by the client after network roaming in order to resolve the ASA IP address used for re-establishing the VPN session. This setting is critical to support roaming between networks of different IP protocols (such as IPv4 to IPv6). Note You cannot use the ASA FQDN present in the AnyConnect profile to derive the ASA IP address after roaming. The addresses may not match the correct device (the one the tunnel was established to) in the load balancing scenario. If the device FQDN is not pushed to the client, the client will try to reconnect to whatever IP address the tunnel had previously established. In order to support roaming between networks of different IP protocols (from IPv4 to IPv6), AnyConnect must perform name resolution of the device FQDN after roaming, so that it can determine which ASA address to use for re-establishing the tunnel. The client uses the ASA FQDN present in its profile during the initial connection. During subsequent session reconnects, it always uses the device FQDN pushed by ASA (and configured by the administrator in the group policy), when available. If the FQDN is not configured, the ASA derives the device FQDN (and sends it to the client) from whatever is set under Device Setup > Device Name/Password and Domain Name. If the device FQDN is not pushed by the ASA, the client cannot re-establish the VPN session after roaming between networks of different IP protocols. • MTU—Adjusts the MTU size for SSL connections. Enter a value in bytes, from 256 to 1410 bytes. By default, the MTU size is adjusted automatically based on the MTU of the interface that the connection uses, minus the IP/UDP/DTLS overhead. • Keepalive Messages—Enter a number, from 15 to 600 seconds, in the Interval field to enable and adjust the interval of keepalive messages to ensure that an connection through a proxy, firewall, or NAT device remains open, even if the device limits the time that the connection can be idle. Adjusting the interval also ensures that the client does not disconnect and reconnect when the remote user is not actively running a socket-based application, such as Microsoft Outlook or Microsoft Internet Explorer. • Optional Client Modules to Download—To minimize download time, the AnyConnect client requests downloads (from the ASA) only of modules that it needs for each feature that it supports. You must specify the names of modules that enable other features. The AnyConnect client, version 3.0, includes the following modules (previous versions have fewer modules): – AnyConnect DART—The Diagnostic AnyConnect Reporting Tool (DART) captures a snapshot of system logs and other diagnostic information and creates a .zip file on your desktop so you can conveniently send troubleshooting information to Cisco TAC. – AnyConnect Network Access Manager—Formerly called the Cisco Secure Services Client, this module provides 802.1X (Layer 2) and device authentication for access to both wired and wireless network is integrated into AnyConnect 3.0. – AnyConnect SBL—Start Before Logon (SBL) forces the user to connect to the enterprise infrastructure over a VPN connection before logging on to Windows by starting AnyConnect before the Windows login dialog box appears. – AnyConnect Web Security Module—Formerly called ScanSafe Hostscan, this module is integrated into the AnyConnect 3.0. Cisco ASA Series VPN ASDM Configuration Guide 4-20 Chapter 4 General VPN Setup Group Policies – AnyConnect Telemetry Module—Sends information about the origin of malicious content to the web filtering infrastructure of the Cisco IronPort Web Security Appliance (WSA), which uses this data to provide better URL filtering rules. – AnyConnect Posture Module—Formerly called the Cisco Secure Desktop HostScan feature, the posture module is integrated into AnyConnect 3.0 and provides AnyConnect the ability to gather credentials for posture assessment prior to creating a remote access connection to the ASA. • Always-On VPN—Determine if the always-on VPN flag setting in the AnyConnect service profile is disabled or if the AnyConnect service profile setting should be used. The always-on VPN feature lets AnyConnnect automatically establish a VPN session after the user logs onto a computer. The VPN session remains up until the user logs off the computer. If the physical connection is lost, the session remains up, and AnyConnect continually attempts to reestablish the physical connection with the adaptive security appliance to resume the VPN session. Always-on VPN permits the enforcement of corporate policies to protect the device from security threats. You can use it to help ensure AnyConnect establishes a VPN session whenever the endpoint is not in a trusted network. If enabled, a policy is configured to determine how network connectivity is managed in the absence of a connection. Note • Always-On VPN requires an AnyConnect release that supports AnyConnect Secure Mobility features. Refer to the Cisco AnyConnect VPN Client Administrator Guide for additional information. Client Profiles to Download—A profile is a group of configuration parameters that the AnyConnect client uses to configure VPN, Network Access Manager, web security, and telemetry settings. Click Add to launch the Select Anyconnect Client Profiles window where you can specify previously-created profiles for this group policy. Configuring AnyConnect Login Settings for an Internal Group Policy In this dialog box, you can enable the ASA to prompt remote users to download the AnyConnect client or go to a Clientless SSL VPN portal page. Figure 4-1 shows the prompt displayed: Figure 4-1 Prompt Displayed to Remote Users for AnyConnect Client Download Fields • Post Login Setting—Choose to prompt the user and set the timeout to perform the default post login selection. • Default Post Login Selection—Choose an action to perform after login. Cisco ASA Series VPN ASDM Configuration Guide 4-21 Chapter 4 General VPN Setup Group Policies Configuring AnyConnect Client Client Firewall Attributes for an Internal Group Policy In ASA 9.0 and later releases, access control lists for client firewalls support both access control entries for both IPv4 and IPv6 addresses. See Client Firewall with Local Printer and Tethered Device Support, page 4-43 to configure the group policy for these situations. Configuring AnyConnect Client Key Regeneration for an Internal Group Policy Rekey Negotiation occurs when the security appliance and the client perform a rekey and they renegotiate the crypto keys and initialization vectors, increasing the security of the connection. Fields • Renegotiation Interval—Uncheck the Unlimited check box to specify the number of minutes from the start of the session until the rekey takes place, from 1 to 10080 (1 week). • Renegotiation Method—Uncheck the Inherit check box to specify a renegotiation method different from the default group policy. Select the None radio button to disable rekey, select either the SSL or New Tunnel radio button to establish a new tunnel during rekey. Note Configuring the Renegotiation Method as SSL or New Tunnel specifies that the client establishes a new tunnel during rekey instead of the SSL renegotiation taking place during the rekey. See the Cisco ASA 5500 Series Command Reference, 8.4 for a history of the anyconnect ssl rekey command. Configuring AnyConnect Client Dead Peer Detection for an Internal Group Policy Dead Peer Detection (DPD) ensures that the security appliance (gateway) or the client can quickly detect a condition where the peer is not responding, and the connection has failed. If DPD is enabled on the ASA, you can use the Optimal MTU (OMTU) function to find the largest endpoint MTU at which the client can successfully pass DTLS packets. Implement OMTU by sending a padded DPD packet to the maximum MTU. If a correct echo of the payload is received from the head end, the MTU size is accepted. Otherwise, the MTU is reduced, and the probe is sent again until the minimum MTU allowed for the protocol is reached. Note Using OMTU does not interfere with the existing tunnel DPD function. Limitations This feature does not work with IPsec, since DPD is based on the standards implementation that does not allow padding. Fields • Gateway Side Detection—Uncheck the Disable check box to specify that DPD is performed by the security appliance (gateway). Enter the interval, from 30 to 3600 seconds, with which the security appliance performs DPD. • Client Side Detection—Uncheck the Disable check box to specify that DPD is performed by the client. Enter the interval, from 30 to 3600 seconds, with which the client performs DPD. Cisco ASA Series VPN ASDM Configuration Guide 4-22 Chapter 4 General VPN Setup Group Policies Customizing a VPN Access Portal for an Internal Group Policy To configure customization for a group policy, select a preconfigured portal customization object, or accept the customization provided in the default group policy. You can also configure a URL to display Fields • Portal Customization—Selects the customization to apply to the AnyConnect Client/SSL VPN portal page. The default is DfltCustomization. – Inherit—To inherit a portal customization from the default group policy, check Inherit. To specify a previously configured customization object, uncheck Inherit and choose the customization object from the drop-down list. – Manage—Opens the Configure GUI Customization objects dialog box, in which you can specify that you want to add, edit, delete, import, or export a customization object. • Note • Homepage URL (optional)—To specify a homepage URL for users associated with the group policy, enter it in this field. The string must begin with either http:// or https://. To inherit a home page from the default group policy, click Inherit. Clientless users are immediately brought to this page after successful authentication. AnyConnect launches the default web browser to this URL upon successful establishment of the VPN connection. AnyConnect does not currently support this field on the Linux platform, Android mobile devices, and Apple iOS mobile devices. If set, it will be ignored by these AnyConnect clients. Access Deny Message—To create a message to users for whom access is denied, enter it in this field. To accept the message in the default group policy, click Inherit. The default message, if you deselect Inherit, is: “Login was successful, but because certain criteria have not been met or due to some specific group policy, you do not have permission to use any of the VPN features. Contact your IT administrator for more information.” Configuring AnyConnect Client Custom Attributes for an Internal Group Policy This dialog box lists the custom attributes that are assigned to this group policy. Custom attributes can be created in this dialog, or on Configuration > Remote Access VPN > Network (Client) Access > Advanced > AnyConnect Custom Attributes. In this dialog, you can add custom attributes to this group policy, and define values for those attributes. For AnyConnect 3.1, custom attributes are available to support AnyConnect Deferred Upgrade and Phone Home. See the Cisco AnyConnect Secure Mobility Client Administrator Guide, Release 3.1, Chapter 2, “User Control Over Upgrade” for more information about the deferred upgrade custom attributes. IPsec (IKEv1) Client Configuring IPsec (IKEv1) Client General Attributes for an Internal Group Policy Configuration > Remote Access > Network (Client) Access > Group Policies > Advanced > IPsec (IKEv1) Client The Add or Edit Group Policy > IPsec dialog box lets you specify tunneling protocols, filters, connection settings, and servers for the group policy being added or modified. Cisco ASA Series VPN ASDM Configuration Guide 4-23 Chapter 4 General VPN Setup Group Policies Fields • Re-Authentication on IKE Re-key—Enables or disables reauthentication when IKE re-key occurs, unless the Inherit check box is checked. The user has 30 seconds to enter credentials, and up to three attempts before the SA expires at approximately two minutes and the tunnel terminates. • Allow entry of authentication credentials until SA expires—Allows users the time to reenter authentication credentials until the maximum lifetime of the configured SA. • IP Compression—Enables or disables IP Compression, unless the Inherit check box is checked. • Perfect Forward Secrecy—Enables or disables perfect forward secrecy (PFS), unless the Inherit check box is selected. PFS ensures that the key for a given IPsec SA was not derived from any other secret (like some other keys). In other words, if someone were to break a key, PFS ensures that the attacker would not be able to derive any other key. If PFS were not enabled, someone could hypothetically break the IKE SA secret key, copy all the IPsec protected data, and then use knowledge of the IKE SA secret to compromise the IPsec SAs set up by this IKE SA. With PFS, breaking IKE would not give an attacker immediate access to IPsec. The attacker would have to break each IPsec SA individually. • Store Password on Client System—Enables or disables storing the password on the client system. Note Storing the password on a client system can constitute a potential security risk. • IPsec over UDP—Enables or disables using IPsec over UDP. • IPsec over UDP Port—Specifies the UDP port to use for IPsec over UDP. • Tunnel Group Lock—Enables locking the tunnel group you select from the list, unless the Inherit check box or the value None is selected. • IPsec Backup Servers—Activates the Server Configuration and Server IP Addresses fields, so you can specify the UDP backup servers to use if these values are not inherited. – Server Configuration—Lists the server configuration options to use as an IPsec backup server. The available options are: Keep Client Configuration (the default), Use the Backup Servers Below, and Clear Client Configuration. – Server Addresses (space delimited)—Specifies the IP addresses of the IPsec backup servers. This field is available only when the value of the Server Configuration selection is Use the Backup Servers Below. Configuring IPsec (IKEv1) Client Client Access Rules for an Internal Group Policy The Client Access Rules table on this dialog box lets you view up to 25 client access rules. If you uncheck the Inherit check box, the Add, Edit, and Delete buttons become active and the following column headings appear in the table: • Priority—Shows the priority for this rule. • Action—Specifies whether this rule permits or denies access. • VPN Client Type—Specifies the type of VPN client to which this rule applies, software or hardware, and for software clients, all Windows clients or a subset. • VPN Client Version—Specifies the version or versions of the VPN client to which this rule applies. This column contains a comma-separated list of software or firmware images appropriate for this client. Cisco ASA Series VPN ASDM Configuration Guide 4-24 Chapter 4 General VPN Setup Group Policies Configuring IPsec (IKEv1) Client Client Firewall Attributes for an Internal Group Policy Configuration > Remote Access > Network (Client) Access > Group Policies > Advanced > IPsec (IKEv1) Client > Client Firewall Tab The Add or Edit Group Policy Client Firewall dialog box lets you configure firewall settings for VPN clients for the group policy being added or modified. Note Only VPN clients running Microsoft Windows can use these firewall features. They are currently not available to hardware clients or other (non-Windows) software clients. A firewall isolates and protects a computer from the Internet by inspecting each inbound and outbound individual packet of data to determine whether to allow or drop it. Firewalls provide extra security if remote users in a group have split tunneling configured. In this case, the firewall protects the user’s PC, and thereby the corporate network, from intrusions by way of the Internet or the user’s local LAN. Remote users connecting to the ASA with the VPN client can choose the appropriate firewall option. In the first scenario, a remote user has a personal firewall installed on the PC. The VPN client enforces firewall policy defined on the local firewall, and it monitors that firewall to make sure it is running. If the firewall stops running, the VPN client drops the connection to the ASA. (This firewall enforcement mechanism is called Are You There (AYT), because the VPN client monitors the firewall by sending it periodic “are you there?” messages; if no reply comes, the VPN client knows the firewall is down and terminates its connection to the ASA.) The network administrator might configure these PC firewalls originally, but with this approach, each user can customize his or her own configuration. In the second scenario, you might prefer to enforce a centralized firewall policy for personal firewalls on VPN client PCs. A common example would be to block Internet traffic to remote PCs in a group using split tunneling. This approach protects the PCs, and therefore the central site, from intrusions from the Internet while tunnels are established. This firewall scenario is called push policy or Central Protection Policy (CPP). On the ASA, you create a set of traffic management rules to enforce on the VPN client, associate those rules with a filter, and designate that filter as the firewall policy. The ASA pushes this policy down to the VPN client. The VPN client then in turn passes the policy to the local firewall, which enforces it. Fields • Inherit—Determines whether the group policy obtains its client firewall setting from the default group policy. This option is the default setting. When set, it overrides the remaining attributes in this dialog boxing dims their names. • Client Firewall Attributes—Specifies the client firewall attributes, including what type of firewall (if any) is implemented and the firewall policy for that firewall. • Firewall Setting—Lists whether a firewall exists, and if so, whether it is required or optional. If you select No Firewall (the default), none of the remaining fields on this dialog box are active. If you want users in this group to be firewall-protected, select either the Firewall Required or Firewall Optional setting. If you choose Firewall Required, all users in this group must use the designated firewall. The ASA drops any session that attempts to connect without the designated, supported firewall installed and running. In this case, the ASA notifies the VPN client that its firewall configuration does not match. Note If you require a firewall for a group, make sure the group does not include any clients other than Windows VPN clients. Any other clients in the group (including ASA 5505 in client mode and VPN 3002 hardware clients) are unable to connect. Cisco ASA Series VPN ASDM Configuration Guide 4-25 Chapter 4 General VPN Setup Group Policies If you have remote users in this group who do not yet have firewall capacity, choose Firewall Optional. The Firewall Optional setting allows all the users in the group to connect. Those who have a firewall can use it; users that connect without a firewall receive a warning message. This setting is useful if you are creating a group in which some users have firewall support and others do not—for example, you may have a group that is in gradual transition, in which some members have set up firewall capacity and others have not yet done so. • Firewall Type—Lists firewalls from several vendors, including Cisco. If you select Custom Firewall, the fields under Custom Firewall become active. The firewall you designate must correlate with the firewall policies available. The specific firewall you configure determines which firewall policy options are supported. • Custom Firewall—Specifies the vendor ID, Product ID and description for the custom firewall. – Vendor ID—Specifies the vendor of the custom firewall for this group policy. – Product ID—Specifies the product or model name of the custom firewall being configured for this group policy. – Description—(Optional) Describes the custom firewall. • Firewall Policy—Specifies the type and source for the custom firewall policy. – Policy defined by remote firewall (AYT)—Specifies that the firewall policy is defined by the remote firewall (Are You There). Policy defined by remote firewall (AYT) means that remote users in this group have firewalls located on their PCs. The local firewall enforces the firewall policy on the VPN client. The ASA allows VPN clients in this group to connect only if they have the designated firewall installed and running. If the designated firewall is not running, the connection fails. Once the connection is established, the VPN client polls the firewall every 30 seconds to make sure that it is still running. If the firewall stops running, the VPN client ends the session. – Policy pushed (CPP)—Specifies that the policy is pushed from the peer. If you choose this option, the Inbound Traffic Policy and Outbound Traffic Policy lists and the Manage button become active. The ASA enforces on the VPN clients in this group the traffic management rules defined by the filter you choose from the Policy Pushed (CPP) drop-down menu. The choices available on the menu are filters defined on this ASA, including the default filters. Keep in mind that the ASA pushes these rules down to the VPN client, so you should create and define these rules relative to the VPN client, not the ASA. For example, “in” and “out” refer to traffic coming into the VPN client or going outbound from the VPN client. If the VPN client also has a local firewall, the policy pushed from the ASA works with the policy of the local firewall. Any packet that is blocked by the rules of either firewall is dropped. – Inbound Traffic Policy—Lists the available push policies for inbound traffic. – Outbound Traffic Policy—Lists the available push policies for outbound traffic. – Manage—Displays the ACL Manager dialog box, in which you can configure Access Control Lists (ACLs). Configuring IPsec (IKEv1) Client Hardware Client Attributes for an Internal Group Policy Configuration > Remote Access > Network (Client) Access > Group Policies > Advanced > IPsec (IKEv1) Client > Hardware Client The Add or Edit Group Policy > Hardware Client dialog box lets you configure settings for the VPN 3002 hardware client for the group policy being added or modified. The Hardware Client dialog box parameters do not pertain to the ASA 5505 in client mode. Cisco ASA Series VPN ASDM Configuration Guide 4-26 Chapter 4 General VPN Setup Group Policies Fields • Inherit—(Multiple instances) Indicates that the corresponding setting takes its value from the default group policy, rather than from the explicit specifications that follow. This is the default setting for all attributes in this dialog box. • Require Interactive Client Authentication—Enables or disables the requirement for interactive client authentication. This parameter is disabled by default. Interactive hardware client authentication provides additional security by requiring the VPN 3002 to authenticate with a username and password that you enter manually each time the VPN 3002 initiates a tunnel. With this feature enabled, the VPN 3002 does not have a saved username and password. When you enter the username and password, the VPN 3002 sends these credentials to the ASA to which it connects. The ASA facilitates authentication, on either the internal or an external authentication server. If the username and password are valid, the tunnel is established. When you enable interactive hardware client authentication for a group, the ASA pushes that policy to the VPN 3002s in the group. If you have previously set a username and password on the VPN 3002, the software deletes them from the configuration file. When you try to connect, the software prompts you for a username and password. If, on the ASA, you subsequently disable interactive hardware authentication for the group, it is enabled locally on the VPN 3002s, and the software continues to prompt for a username and password. This lets the VPN 3002 connect, even though it lacks a saved username and password, and the ASA has disabled interactive hardware client authentication. If you subsequently configure a username and password, the feature is disabled, and the prompt no longer appears. The VPN 3002 connects to the ASA using the saved username and password. • Require Individual User Authentication—Enables or disables the requirement for individual user authentication for users behind ASA 5505 in client mode or the VPN 3002 hardware client in the group. To display a banner to hardware clients in a group, individual user authentication must be enabled. This parameter is disabled by default. Individual user authentication protects the central site from access by unauthorized persons on the private network of the hardware client. When you enable individual user authentication, each user that connects through a hardware client must open a web browser and manually enter a valid username and password to access the network behind the ASA, even though the tunnel already exists. Note You cannot use the command-line interface to log in if user authentication is enabled. You must use a browser. If you have a default home page on the remote network behind the ASA, or if you direct the browser to a website on the remote network behind the ASA, the hardware client directs the browser to the proper pages for user login. When you successfully log in, the browser displays the page you originally entered. If you try to access resources on the network behind the ASA that are not web-based, for example, e-mail, the connection fails until you authenticate using a browser. To authenticate, you must enter the IP address for the private interface of the hardware client in the browser Location or Address field. The browser then displays the login dialog box for the hardware client. To authenticate, click Connect/Login Status. One user can log in for a maximum of four sessions simultaneously. Individual users authenticate according to the order of authentication servers configured for a group. Cisco ASA Series VPN ASDM Configuration Guide 4-27 Chapter 4 General VPN Setup Group Policies • User Authentication Idle Timeout—Configures a user timeout period. The security appliance terminates the connection if it does not receive user traffic during this period. You can specify that the timeout period is a specific number of minutes or unlimited. – Unlimited—Specifies that the connection never times out. This option prevents inheriting a value from a default or specified group policy. – Minutes—Specifies the timeout period in minutes. Use an integer between 1 and 35791394. The default value is Unlimited. Note that the idle timeout indicated in response to the show uauth command is always the idle timeout value of the user who authenticated the tunnel on the Cisco Easy VPN remote device. • Cisco IP Phone Bypass—Lets Cisco IP Phones bypass the interactive individual user authentication processes. If enabled, interactive hardware client authentication remains in effect. Cisco IP Phone Bypass is disabled by default. Note You must configure the ASA 5505 in client mode or the VPN 3002 hardware client to use network extension mode for IP phone connections. • LEAP Bypass—Lets LEAP packets from Cisco wireless devices bypass the individual user authentication processes (if enabled). LEAP Bypass lets LEAP packets from devices behind a hardware client travel across a VPN tunnel prior to individual user authentication. This lets workstations using Cisco wireless access point devices establish LEAP authentication. Then they authenticate again per individual user authentication (if enabled). LEAP Bypass is disabled by default. Note This feature does not work as intended if you enable interactive hardware client authentication. IEEE 802.1X is a standard for authentication on wired and wireless networks. It provides wireless LANs with strong mutual authentication between clients and authentication servers, which can provide dynamic per-user, per-session wireless encryption privacy (WEP) keys, removing administrative burdens and security issues that are present with static WEP keys. Cisco Systems has developed an 802.1X wireless authentication type called Cisco LEAP. LEAP implements mutual authentication between a wireless client on one side of a connection and a RADIUS server on the other side. The credentials used for authentication, including a password, are always encrypted before they are transmitted over the wireless medium. Note Cisco LEAP authenticates wireless clients to RADIUS servers. It does not include RADIUS accounting services. LEAP users behind a hardware client have a circular dilemma: they cannot negotiate LEAP authentication because they cannot send their credentials to the RADIUS server behind the central site device over the tunnel. The reason they cannot send their credentials over the tunnel is that they have not authenticated on the wireless network. To solve this problem, LEAP Bypass lets LEAP packets, and only LEAP packets, traverse the tunnel to authenticate the wireless connection to a RADIUS server before individual users authenticate. Then the users proceed with individual user authentication. LEAP Bypass works as intended under the following conditions: Cisco ASA Series VPN ASDM Configuration Guide 4-28 Chapter 4 General VPN Setup Group Policies – The interactive unit authentication feature (intended for wired devices) must be disabled. If interactive unit authentication is enabled, a non-LEAP (wired) device must authenticate the hardware client before LEAP devices can connect using that tunnel. – Individual user authentication is enabled (if it is not, you do not need LEAP Bypass). – Access points in the wireless environment must be Cisco Aironet Access Points. The wireless NIC cards for PCs can be other brands. – The Cisco Aironet Access Point must be running Cisco Discovery Protocol (CDP). – The ASA 5505 or VPN 3002 can operate in either client mode or network extension mode. – LEAP packets travel over the tunnel to a RADIUS server via ports 1645 or 1812. Note • Allowing any unauthenticated traffic to traverse the tunnel might pose a security risk. Allow C—Restricts the use of Network Extension Mode on the hardware client. Choose the option to let hardware clients use Network Extension Mode. Network Extension Mode is required for the hardware client to support IP phone connections, because the Call Manager can communicate only with actual IP addresses. If you disable network extension mode, the default setting, the hardware client can connect to this ASA in PAT mode only. If you disallow network extension mode here, be careful to configure all hardware clients in a group for PAT mode. If a hardware client is configured to use Network Extension Mode and the ASA to which it connects disables Network Extension Mode, the hardware client attempts to connect every 4 seconds, and every attempt is rejected. In this situation, the hardware client puts an unnecessary processing load on the ASA to which it connects; large numbers of hardware clients that are misconfigured in this way reduces the ability of the security appliance to provide service. Note Configuring Clientless SSL VPN Internal Group Policies Configuring Clientless SSL VPN General Attributes for an Internal Group Policy Configuration > Remote Access VPN > Clientless SSL VPN Access > Group Policies > Add/Edit > Add or Edit Internal Group Policy > General The Add or Edit Group Policy dialog box lets you specify tunneling protocols, filters, connection settings, and servers for the group policy being added or modified. For each of the fields on this dialog box, checking the Inherit check box lets the corresponding setting take its value from the default group policy. Inherit is the default value for all of the attributes in this dialog box. Fields The following attributes appear in the Add Internal Group Policy > General dialog box. They apply to SSL VPN and IPsec sessions, or clientless SSL VPN sessions. Thus, several are present for one type of session, but not the other. • Name—Specifies the name of this group policy up to 64 characters; spaces are allowed. For the Edit function, this field is read-only. • Banner—Specifies the banner text to present to users at login. The length can be up to 491 characters. There is no default value. Cisco ASA Series VPN ASDM Configuration Guide 4-29 Chapter 4 General VPN Setup Group Policies The IPsec VPN client supports full HTML for the banner. However, the clientless portal and the AnyConnect client support partial HTML. To ensure the banner displays properly to remote users, follow these guidelines: – For clientless users, use the
tag. • Tunneling Protocols—Specifies the tunneling protocols that this group can use. Users can use only the selected protocols. The choices are as follows: – Clientless SSL VPN—Specifies the use of VPN via SSL/TLS, which uses a web browser to establish a secure remote-access tunnel to an ASA; requires neither a software nor hardware client. Clientless SSL VPN can provide easy access to a broad range of enterprise resources, including corporate websites, web-enabled applications, NT/AD file share (web-enabled), e-mail, and other TCP-based applications from almost any computer that can reach HTTPS Internet sites. – SSL VPN Client—Specifies the use of the Cisco AnyConnect VPN client or the legacy SSL VPN client. If you are using the AnyConnect client, you must choose this protocol for MUS to be supported. – IPsec IKEv1—IP Security Protocol. Regarded as the most secure protocol, IPsec provides the most complete architecture for VPN tunnels. Both Site-to-Site (peer-to-peer) connections and Cisco VPN client-to-LAN connections can use IPsec IKEv1. – IPsec IKEv2—Supported by the AnyConnect Secure Mobility Client. AnyConnect connections using IPsec with IKEv2 provide advanced features such as software updates, client profiles, GUI localization (translation) and customization, Cisco Secure Desktop, and SCEP proxy. – L2TP over IPsec—Allows remote users with VPN clients provided with several common PC and mobile PC operating systems to establish secure connections over the public IP network to the security appliance and private corporate networks. L2TP uses PPP over UDP (port 1701) to tunnel the data. The security appliance must be configured for IPsec transport mode. Note If you do not select a protocol, an error message appears. • Web ACL—(Clientless SSL VPN only) Choose an access control list (ACL) from the drop-down list if you want to filter traffic. Click Manage next to the list if you want to view, modify, add, or remove ACLs before making a selection. • Manage—Displays the ACL Manager dialog box, with which you can add, edit, and delete Access Control Lists (ACLs) and Extended Access Control Lists (ACEs). For more information about the ACL Manager, see the online Help for that dialog box. • Access Hours—Selects the name of an existing access hours policy, if any, applied to this user or create a new access hours policy. The default value is Inherit, or, if the Inherit check box is not checked, the default value is --Unrestricted--. • Manage—Opens the Browse Time Range dialog box, in which you can add, edit, or delete a time range. See Defining Time Ranges, page 4-35 for more information. • Simultaneous Logins—Specifies the maximum number of simultaneous logins allowed for this user. The default value is 3. The minimum value is 0, which disables login and prevents user access. Note While there is no maximum limit, allowing several simultaneous connections might compromise security and affect performance. Cisco ASA Series VPN ASDM Configuration Guide 4-30 Chapter 4 General VPN Setup Group Policies • Restrict Access to VLAN—(Optional) Also called “VLAN mapping,” this parameter specifies the egress VLAN interface for sessions to which this group policy applies. The ASA forwards all traffic on this group to the selected VLAN. Use this attribute to assign a VLAN to the group policy to simplify access control. Assigning a value to this attribute is an alternative to using ACLs to filter traffic on a session. In addition to the default value (Unrestricted), the drop-down list shows only the VLANs that are configured on this ASA. This feature works for HTTP connections, but not for FTP and CIFS. Note • Connection Profile (Tunnel Group) Lock—This parameter permits remote VPN access only with the selected connection profile (tunnel group), and prevents access with a different connection profile. The default inherited value is None. • Maximum Connect Time—If the Inherit check box is not checked, this parameter specifies the maximum user connection time in minutes. At the end of this time, the system terminates the connection. The minimum is 1 minute, and the maximum is 35791394 minutes (over 4000 years). To allow unlimited connection time, check Unlimited (the default). • Idle Timeout—If the Inherit check box is not checked, this parameter specifies this user’s idle timeout period in minutes. If there is no communication activity on the user connection in this period, the system terminates the connection. The minimum time is 1 minute, and the maximum time is 10080 minutes. The default is 30 minutes. To allow unlimited connection time, check Unlimited. This value does not apply to Clientless SSL VPN users. • Session Alert Interval— If you uncheck the Inherit check box, the Default checkbox is checked automatically. This sets the session alert interval to 30 minutes. If you want to specify a new value, uncheck the Default check box and specify a session alert interval from 1 to 30 minutes in the minutes box. • Idle Alert Interval—If you uncheck the Inherit check box, the Default checkbox is checked automatically. This sets the idle alert interval to 30 minutes. If you want to specify a new value, uncheck the Default check box and specify a session alert interval from 1 to 30 minutes in the minutes box. Configuring the Clientless SSL VPN Access Portal for an Internal Group Policy The Portal attributes determine what appears on the portal page for members of this group policy establishing Clientless SSL VPN connections. In this pane, you can enable Bookmark lists and URL Entry, file server access, Port Forwarding and Smart Tunnels, ActiveX Relay, and HTTP settings. Fields • Bookmark List—Choose a previously-configured Bookmark list or click Manage to create a new one. Bookmarks appear as links, from which users can navigate from the portal page. • URL Entry—Enable to allow remote users to enter URLs directly into the portal URL field. • File Access Control—Controls the visibility of “hidden shares” for Common Internet File System (CIFS) files. A hidden share is identified by a dollar sign ($) at the end of the share name. For example, drive C is shared as C$. With hidden shares, a shared folder is not displayed, and users are restricted from browsing or accessing these hidden resources. – File Server Entry—Enable to allow remote users to enter the name of a file server. – File Server Browsing—Enable to allow remote users to browse for available file servers. – Hidden Share Access—Enable to hide shared folders. Cisco ASA Series VPN ASDM Configuration Guide 4-31 Chapter 4 General VPN Setup Group Policies • Port Forwarding Control—Provides users access to TCP-based applications over a Clientless SSL VPN connection through a Java Applet. – Port Forwarding List—Choose a previously-configured list TCP applications to associate with this group policy. Click Manage to create a new list or to edit an existing list. – Auto Applet Download—Enables automatic installation and starting of the Applet the first time the user logs in. – Applet Name—Changes the name of the title bar that of the Applet dialog box to the name you designate. By default, the name is Application Access. • Smart Tunnel—Specify your smart tunnel options using a clientless (browser-based) SSL VPN session with the ASA as the pathway and the security appliance as a proxy server: – Smart Tunnel Policy—Choose from the network list and specify one of the tunnels options: use smart tunnel for the specified network, do not use smart tunnel for the specified network, or use tunnel for all network traffic. Assigning a smart tunnel network to a group policy or username enables smart tunnel access for all users whose sessions are associated with the group policy or username but restricts smart tunnel access to the applications specified in the list. To view, add, modify, or delete a smart tunnel list, click Manage. – Smart Tunnel Application—Choose from the drop-down menu to connect a Winsock 2, TCP-based application installed on the end station to a server on the intranet. To view, add, modify, or delete a smart tunnel application, click Manage. – Smart Tunnel all Applications—Check this check box to tunnel all applications. All applications are tunneled without choosing from the network list or knowing which executables an end user may invoke for external applications. – Auto Start—Check this check box to start smart tunnel access automatically upon user login. This option to start smart tunnel access upon user login applies only to Windows. Uncheck the check box to enable smart tunnel access upon user login but require the user to start it manually, using the Application Access > Start Smart Tunnels button on the Clientless SSL VPN Portal Page. – Auto Sign-on Server List—Choose the list name from the drop-down menu if you want to reissue the user credentials when the user establishes a smart tunnel connection to a server. Each smart tunnel auto sign-on list entry identifies a server with which to automate the submission of user credentials. To view, add, modify, or delete a smart tunnel auto sign-on list, click Manage. – Windows Domain Name (Optional)—Specify the Windows domain to add it to the username during auto sign-on, if the universal naming convention (domain\username) is required for authentication. For example, enter CISCO to specify CISCO\qa_team when authenticating for the username qu_team. You must also check the “Use Windows domain name with user name” option when configuring associated entries in the auto sign-on server list. • ActiveX Relay—Lets Clientless users launch Microsoft Office applications from the browser. The applications use the session to download and upload Microsoft Office documents. The ActiveX relay remains in force until the Clientless SSL VPN session closes. More Options: • HTTP Proxy—Enables or disables the forwarding of an HTTP applet proxy to the client. The proxy is useful for technologies that interfere with proper content transformation, such as Java, ActiveX, and Flash. It bypasses mangling while ensuring the continued use of the security appliance. The forwarded proxy automatically modifies the old browser proxy configuration and redirects all HTTP and HTTPS requests to the new proxy configuration. It supports virtually all client side technologies, including HTML, CSS, JavaScript, VBScript, ActiveX, and Java. The only browser it supports is Microsoft Internet Explorer. Cisco ASA Series VPN ASDM Configuration Guide 4-32 Chapter 4 General VPN Setup Group Policies • Auto Start (HTTP Proxy)—Check to enable HTTP Proxy automatically upon user login. Uncheck to enable smart tunnel access upon user login, but require the user to start it manually. • HTTP Compression—Enables compression of HTTP data over the Clientless SSL VPN session. Configuring Portal Customization for a Clientless SSL VPN Internal Group Policy To configure customization for a group policy, select a preconfigured portal customization object, or accept the customization provided in the default group policy. You can also configure a URL to display. The procedure for customizing an access portal for a Clientless SSL VPN Access connection is the same as it is for a Network Client Access connection. See Customizing a VPN Access Portal for an Internal Group Policy, page 4-23. Configuring Login Settings for a Clientless SSL VPN Internal Group Policy In this dialog box, you can enable the ASA to prompt remote users to download the AnyConnect client or go to a Clientless SSL VPN portal page. See Configuring AnyConnect Login Settings for an Internal Group Policy, page 4-21. Configuring Single Signon and Auto Signon Servers for a Clientless SSL VPN Access Internal Group Policy To configure single sign-on servers and Auto sign-on servers, see “Auto Signon” in Chapter 71, “Clientless SSL VPN” in Cisco ASA 5500 Series Configuration Guide using ASDM, 6.4 and 6.6 or “Using Single Sign-on with Clientless SSL VPN” in Chapter 73 of Cisco ASA 5500 Series Configuration Guide using the CLI, 8.4 and 8.6. Configuring Session Settings for Clientless SSL VPN Access The clientless SSL VPN Add/Edit Internal Group Policy > More Options > Session Settings window lets you specify personalized user information between clientless SSL VPN sessions. By default, each group policy inherits the settings from the default group policy. Use this window to specify personalized clientless SSL VPN user information for the default group policy and any group policies for which you want to differentiate these values. See “Configuring Session Settings” Chapter 71, “Clientless SSL VPN” in Cisco ASA 5500 Series Configuration Guide using ASDM, 6.4 and 6.6 or in Chapter 73 of Cisco ASA 5500 Series Configuration Guide using the CLI, 8.4 and 8.6. Configuring Site-to-Site Internal Group Policies Configuration > Remote Access VPN > Network (Client) Access > Group Policies > Add/Edit > Add or Edit Internal Group Policy > General The Add or Edit Group Policy dialog box lets you specify tunneling protocols, filters, connection settings, and servers for the group policy being added or modified. For each of the fields in this dialog box, checking the Inherit check box lets the corresponding setting take its value from the default group policy. Inherit is the default value for all of the attributes on this dialog box. Cisco ASA Series VPN ASDM Configuration Guide 4-33 Chapter 4 General VPN Setup Group Policies Fields The following attributes appear in the Add Internal Group Policy > General dialog box. They apply to SSL VPN and IPsec sessions, or clientless SSL VPN sessions. Thus, several are present for one type of session, but not the other. • Name—Specifies the name of this group policy. For the Edit function, this field is read-only. • Tunneling Protocols—Specifies the tunneling protocols that this group can use. Users can use only the selected protocols. The choices are as follows: – Clientless SSL VPN—Specifies the use of VPN via SSL/TLS, which uses a web browser to establish a secure remote-access tunnel to a ASA; requires neither a software nor hardware client. Clientless SSL VPN can provide easy access to a broad range of enterprise resources, including corporate websites, web-enabled applications, NT/AD file share (web-enabled), e-mail, and other TCP-based applications from almost any computer that can reach HTTPS Internet sites. – SSL VPN Client—Specifies the use of the Cisco AnyConnect VPN client or the legacy SSL VPN client. If you are using the AnyConnect client, you must choose this protocol for MUS to be supported. – IPsec IKEv1—IP Security Protocol. Regarded as the most secure protocol, IPsec provides the most complete architecture for VPN tunnels. Both Site-to-Site (peer-to-peer) connections and Cisco VPN client-to-LAN connections can use IPsec IKEv1. – IPsec IKEv2—Supported by the AnyConnect Secure Mobility Client. AnyConnect connections using IPsec with IKEv2 provide advanced features such as software updates, client profiles, GUI localization (translation) and customization, Cisco Secure Desktop, and SCEP proxy. – L2TP over IPsec—Allows remote users with VPN clients provided with several common PC and mobile PC operating systems to establish secure connections over the public IP network to the security appliance and private corporate networks. L2TP uses PPP over UDP (port 1701) to tunnel the data. The security appliance must be configured for IPsec transport mode. Note If you do not select a protocol, an error message appears. • Filter—(Network (Client) Access only) Specifies which access control list to use, or whether to inherit the value from the group policy. Filters consist of rules that determine whether to allow or reject tunneled data packets coming through the ASA, based on criteria such as source address, destination address, and protocol. To configure filters and rules, see the Group Policy dialog box. • Manage—Displays the ACL Manager dialog box, with which you can add, edit, and delete Access Control Lists (ACLs) and Extended Access Control Lists (ACEs). For more information about the ACL Manager, see the online Help for that dialog box. • Idle Timeout—If the Inherit check box is not checked, this parameter specifies this user’s idle timeout period in minutes. If there is no communication activity on the user connection in this period, the system terminates the connection. The minimum time is 1 minute, and the maximum time is 10080 minutes. The default is 30 minutes. To allow unlimited connection time, check Unlimited. This value does not apply to Clientless SSL VPN users. • Maximum Connect Time—If the Inherit check box is not checked, this parameter specifies the maximum user connection time in minutes. At the end of this time, the system terminates the connection. The minimum is 1 minute, and the maximum is 35791394 minutes (over 4000 years). To allow unlimited connection time, check Unlimited (the default). Cisco ASA Series VPN ASDM Configuration Guide 4-34 Chapter 4 General VPN Setup Group Policies Defining Time Ranges You can get to this panel through various paths. Use the Browse Time Range dialog box to add, edit, or delete a time range. A time range is a reusable component that defines starting and ending times that can be applied to a group policy. After defining a time range, you can select the time range and apply it to different options that require scheduling. For example, you can attach an ACL to a time range to restrict access to the ASA. A time range consists of a start time, an end time, and optional recurring (that is, periodic) entries. For more information about time ranges, see the online Help for the Add or Edit Time Range dialog box. Fields • Add—Opens the Add Time Range dialog box, in which you can create a new time range. Creating a time range does not restrict access to the device. Note • Edit—Opens the Edit Time Range dialog box, in which you can modify an existing time range. This button is active only when you have selected an existing time range from the Browse Time Range table. • Delete—Removes a selected time range from the Browse Time Range table. There is no confirmation or undo of this action. • Name—Specifies the name of the time range. • Start Time—Specifies when the time range begins. • End Time—Specifies when the time range ends. • Recurring Entries—Specifies further constraints of active time of the range within the start and stop time specified. Add/Edit Time Range You can get to this panel through various paths. The Add or Edit Time Range dialog box lets you configure a new time range. Fields • Time Range Name—Specifies the name that you want to assign to this time range. • Start Time—Defines the time when you want the time range to start. – Start now—Specifies that the time range starts immediately. – Start at—Selects the month, day, year, hour, and minute at which you want the time range to start. • End Time—Defines the time when you want the time range to end. – Never end—Specifies that the time range has no defined end point. – End at (inclusive)—Selects the month, day, year, hour, and minute at which you want the time range to end. Cisco ASA Series VPN ASDM Configuration Guide 4-35 Chapter 4 General VPN Setup Access Control List Manager • Recurring Time Ranges—Constrains the active time of this time range within the start and end times when the time range is active. For example, if the start time is start now and the end time is never end, and you want the time range to be effective every weekday, Monday through Friday, from 8:00 AM to 5:00 PM, you could configure a recurring time range, specifying that it is to be active weekdays from 08:00 through 17:00, inclusive. • Add—Opens the Add Recurring Time Range dialog box, in which you can configure a recurring time range. • Edit—Opens the Edit Recurring Time Range dialog box, in which you can modify a selected recurring time range. • Delete—Removes a selected recurring time range. Add/Edit Recurring Time Range You can get to this panel through various paths. The Add or Edit Recurring Time Range dialog box lets you configure or modify a recurring time range. Fields • Specify days of the week and times on which this recurring range will be active—Makes available the options in the Days of the week area. For example, use this option when you want the time range to be active only every Monday through Thursday, from 08:00 through 16:59. – Days of the week—Specifies the days that you want to include in this recurring time range. Possible options are: Every day, Weekdays, Weekends, and On these days of the week. For the last of these, you can check a check box for each day that you want included in the range. – Daily Start Time—Specifies the hour and minute, in 24-hour format, when you want the recurring time range to be active on each selected day. – Daily End Time (inclusive)—Specifies the hour and minute, in 24-hour format, when you want the recurring time range to end on each selected day. • Specify a weekly interval when this recurring range will be active—Makes available the options in the Weekly Interval area. The range extends inclusively through the end time. All times in this area are in 24-hour format. For example, use this option when you want the time range to be active continuously from Monday at 8:00 AM through Friday at 4:30 PM. – From—Selects the day, hour, and minute when you want the weekly time range to start. – Through—Selects the day, hour, and minute when you want the weekly time range to end. Access Control List Manager You can get to this panel through various paths. The ACL Manager dialog box lets you define access control lists (ACLs) to control the access of a specific host or network to another host/network, including the protocol or port that can be used. You can configure ACLs (access control lists) to apply to user sessions. These are filters that permit or deny user access to specific networks, subnets, hosts, and web servers. • If you do not define any filters, all connections are permitted. • The ASA supports only an inbound ACL on an interface. Cisco ASA Series VPN ASDM Configuration Guide 4-36 Chapter 4 General VPN Setup Access Control List Manager • At the end of each ACL, there is an implicit, unwritten rule that denies all traffic that is not permitted. If traffic is not explicitly permitted by an access control entry (ACE), the ASA denies it. ACEs are referred to as rules in this section. Standard Access Control List This pane provides summary information about standard ACLs, and lets you add or edit ACLs and ACEs. Fields • Add—Lets you add a new ACL. When you highlight an existing ACL, it lets you add a new ACE for that ACL. • Edit—Opens the Edit ACE dialog box, in which you can change an existing access control list rule. • Delete—Removes an ACL or ACE. There is no confirmation or undo. • Move Up/Move Down—Changes the position of a rule in the ACL Manager table. • Cut—Removes the selection from the ACL Manager table and places it on the clipboard. • Copy—Places a copy of the selection on the clipboard. • Paste—Opens the Paste ACE dialog box, in which you can create a new ACL rule from an existing rule. • No—Indicates the order of evaluation for the rule. Implicit rules are not numbered, but are represented by a hyphen. • Address—Displays the IP address or URL of the application or service to which the ACE applies. • Action—Specifies whether this filter permits or denies traffic flow. • Description—Shows the description you typed when you added the rule. An implicit rule includes the following description: “Implicit outbound rule.” Extended Access Control List This pane provides summary information about extended ACLs, and lets you add or edit ACLs and ACEs. Fields • Add—Lets you add a new ACL. When you highlight an existing ACL, it lets you add a new ACE for that ACL. • Edit—Opens the Edit ACE dialog box, in which you can change an existing access control list rule. • Delete—Removes an ACL or ACE. There is no confirmation or undo. • Move Up/Move Down—Changes the position of a rule in the ACL Manager table. • Cut—Removes the selection from the ACL Manager table and places it on the clipboard. • Copy—Places a copy of the selection on the clipboard. • Paste—Opens the Paste ACE dialog box, in which you can create a new ACL rule from an existing rule. • No—Indicates the order of evaluation for the rule. Implicit rules are not numbered, but are represented by a hyphen. Cisco ASA Series VPN ASDM Configuration Guide 4-37 Chapter 4 General VPN Setup Access Control List Manager • Enabled—Enables or disables a rule. Implicit rules cannot be disabled. • Source—Specifies the IP addresses (Host/Network) that are permitted or denied to send traffic to the IP addresses listed in the Destination column. In detail mode (see the Show Detail radio button), an address column might contain an interface name with the word any, such as inside: any. This means that any host on the inside interface is affected by the rule. • Destination—Specifies the IP addresses (Host/Network) that are permitted or denied to send traffic to the IP addresses listed in the Source column. An address column might contain an interface name with the word any, such as outside: any. This means that any host on the outside interface is affected by the rule. An address column might also contain IP addresses; for example 209.165.201.1-209.165.201.30. These addresses are translated addresses. When an inside host makes a connection to an outside host, the firewall maps the address of the inside host to an address from the pool. After a host creates an outbound connection, the firewall maintains this address mapping. The address mapping structure is called an xlate, and remains in memory for a period of time. During this time, outside hosts can initiate connections to the inside host using the translated address from the pool, if allowed by the ACL. Normally, outside-to-inside connections require a static translation so that the inside host always uses the same IP address. • Service—Names the service and protocol specified by the rule. • Action—Specifies whether this filter permits or denies traffic flow. • Logging—Shows the logging level and the interval in seconds between log messages (if you enable logging for the ACL). To set logging options, including enabling and disabling logging, right-click this column, and click Edit Log Option. The Log Options dialog box appears. • Time—Specifies the name of the time range to be applied in this rule. • Description—Shows the description you typed when you added the rule. An implicit rule includes the following description: “Implicit outbound rule.” Add/Edit/Paste ACE ACL Manager > Add/Edit/Paste Extended ACE The Add/Edit/Paste ACE dialog box lets you create a new extended ACE, or modify an existing rule. The Paste option becomes available only when you cut or copy a rule. Fields • Action—Determines the action type of the new rule. Select either permit or deny. – Permit—Permits all matching traffic. – Deny—Denies all matching traffic. • Source/Destination—Specifies the source or destination type and, depending on that type, the other relevant parameters describing the source or destination host/network IP Address. Possible values are: any, IP address, Network Object Group, and Interface IP. The availability of subsequent fields depends upon the value of the Type field: – any—Specifies that the source or destination host/network can be any type. For this value of the Type field, there are no additional fields in the Source or Destination area. – IP Address—Specifies the source or destination host or network IP address. Both IPv4 and IPv6 addresses are supported. With this selection, the IP Address, ellipsis button, and Netmask fields become available. Choose an IP address or host name from the drop-down list in the IP Address field or click the ellipsis (...) button to browse for an IP address or name. Select a network mask from the drop-down list. Cisco ASA Series VPN ASDM Configuration Guide 4-38 Chapter 4 General VPN Setup Access Control List Manager – Network Object Group—Specifies the name of the network object group. Choose a name from the drop-down list or click the ellipsis (...) button to browse for a network object group name. – Interface IP—Specifies the interface on which the host or network resides. Select an interface from the drop-down list. The default values are inside and outside. There is no browse function. • Protocol and Service—Specifies the protocol and service to which this ACE filter applies. Service groups let you identify multiple non-contiguous port numbers that you want the ACL to match. For example, if you want to filter HTTP, FTP, and port numbers 5, 8, and 9, define a service group that includes all these ports. Without service groups, you would have to create a separate rule for each port. You can create service groups for TCP, UDP, TCP-UDP, ICMP, and other protocols. A service group with the TCP-UDP protocol contains services, ports, and ranges that might use either the TCP or UDP protocol. – Protocol—Selects the protocol to which this rule applies. Possible values are ip, tcp, udp, icmp, and other. The remaining available fields in the Protocol and Service area depend upon the protocol you select. The next few bullets describe the consequences of each of these selections: – Protocol: TCP and UDP—Selects the TCP/UDP protocol for the rule. The Source Port and Destination Port areas allow you to specify the ports that the ACL uses to match packets. – Source Port/Destination Port—(Available only for TCP and UDP protocols) Specifies an operator and a port number, a range of ports, or a well-known service name from a list of services, such as HTTP or FTP. The operator list specifies how the ACL matches the port. Choose one of the following operators: = (equals the port number), not = (does not equal the port number), > (greater than the port number), < (less than the port number), range (equal to one of the port numbers in the range). – Group—(Available only for TCP and UDP protocols) Selects a source port service group. The Browse (...) button opens the Browse Source Port or Browse Destination Port dialog box. – Protocol: ICMP—Lets you choose an ICMP type or ICMP group from a preconfigured list or browse (...) for an ICMP group. The Browse button opens the Browse ICMP dialog box. – Protocol: IP—Specifies the IP protocol for the rule in the IP protocol box. No other fields are available when you make this selection. – Protocol: Other—Lets you choose a protocol from a drop-down list, choose a protocol group from a drop-down list, or browse for a protocol group. The Browse (...) button opens the Browse Other dialog box. • Rule Flow Diagram—(Display only) Provides a graphical representation of the configured rule flow. This same diagram appears on the ACL Manager dialog box unless you explicitly close that display. • Options—Sets optional features for this rule, including logging parameters, time ranges, and description. – Logging—Enables or disables logging or specifies the use of the default logging settings. If logging is enabled, the Syslog Level and Log Interval fields become available. – Syslog Level—Selects the level of logging activity. The default is Informational. – Log Interval—Specifies the interval for permit and deny logging. The default is 300 seconds. The range is 1 through 6000 seconds. – Time Range—Selects the name of the time range to use with this rule. The default is (any). Click the Browse (...) button to open the Browse Time Range dialog box to select or add a time range. – Description—(Optional) Provides a brief description of this rule. A description line can be up to 100 characters long, but you can break a description into multiple lines. Cisco ASA Series VPN ASDM Configuration Guide 4-39 Chapter 4 General VPN Setup Access Control List Manager Browse Source/Destination Address ACL Manager > Add/Edit Extended Access List Rule > Source or Destination > Browse button The Browse Source or Destination Address dialog box lets you select an object to use as a source or destination for this rule. Fields • Type—Determines the type of object to use as the source or destination for this rule. Selections are IP Address Objects, IP Names, Network Object Groups, and All. The contents of the table following this field change, depending upon your selection. • Source/Destination Object Table—Displays the objects from which you can select a source or destination object. If you choose All in the type field, each category of object appears under its own heading. The table has the following headings: – Name—Displays the network name (which may be an IP address) for each object. – IP address—Displays the IP address of each object. – Netmask—Displays the network mask to use with each object. – Description—Displays the description entered in the Add/Edit/Paste Extended Access List Rule dialog box. Browse Source/Destination Port ACL Manager > Add/Edit Extended Access List Rule > Protocol and Service > Protocol: tcp or udp >Source or Destination Port > Group option > Browse button The Browse Source or Destination Port dialog box lets you select a source or destination port for this protocol in this rule. Fields • Add—Opens the Add TCP Service Group dialog box, in which you can configure a new TCP service group. • Find—Opens the Filter field. • Filter/Clear—Specifies a filter criterion that you can use to search for items in the Name list, thus displaying only those items that match that criterion. When you make an entry in the Filter field, the Filter button becomes active. Clicking the Filter button performs the search. After you perform the search, the Filter button is dimmed, and the Clear button becomes active. Clicking the Clear button clears the filter field and dims the Clear button. • Type—Determines the type of object to use as the source or destination for this rule. Selections are IP Address Objects, IP Names, Network Object Groups, and All. The contents of the table following this field change, depending upon your selection. • Name—Lists the predefined protocols and service groups for your selection. Add TCP Service Group ACL Manager > Add/Edit Extended Access List Rule > Protocol and Service > Protocol: tcp or udp >Source or Destination Port > Group option > Browse button > Browse Source or Destination Port > Add button Cisco ASA Series VPN ASDM Configuration Guide 4-40 Chapter 4 General VPN Setup Access Control List Manager The Add TCP Service Group dialog box lets you configure a new a TCP service group or port to add to the browsable source or destination port list for this protocol in this rule. Selecting a member of either the Members not in Group or the Members in Group list activates the Add and Remove buttons. Fields • Group Name—Specifies the name of the new TCP service group. • Description—(Optional) Provides a brief description of this group. • Members not in Group—Presents the option to select either a service/service group or a port number to add to the Members in Group list. • Service/Service Group—Selects the option to select the name of a TCP service or service group to add to the Members in Group list. • Port #—Selects the option to specify a range of port numbers to add to the Members in Group list. • Add—Moves a selected item from the Members not in Group list to the Members in Group list. • Remove—Moves a selected item from the Members in Group list to the Members not in Group list. • Members in Group—Lists the members already configured in this service group. Browse ICMP ACL Manager > Add/Edit Extended Access List Rule > Protocol and Service > Protocol: icmp >ICMP > Group option > Browse button The Browse ICMP dialog box lets you select an ICMP group for this rule. Fields • Add—Opens the Add ICMP Group dialog box, in which you can configure a new TCP service group. • Find—Opens the Filter field. • Filter/Clear—Specifies a filter criterion that you can use to search for items in the Name list, thus displaying only those items that match that criterion. When you make an entry in the Filter field, the Filter button becomes active. Clicking the Filter button performs the search. After you perform the search, the Filter button is dimmed, and the Clear button becomes active. Clicking the Clear button clears the filter field and dims the Clear button. • Type—Determines the type of object to use as the ICMP group for this rule. Selections are IP Address Objects, IP Names, Network Object Groups, and All. The contents of the table following this field change, depending upon your selection. • Name—Lists the predefined ICMP groups for your selection. Add ICMP Group ACL Manager > Add/Edit Extended Access List Rule > Protocol and Service > Protocol: icmp >ICMP > Group option > Browse button > Browse ICMP > Add button The Add ICMP Group dialog box lets you configure a new a ICMP group by name or by number to add to the browsable ICMP list for this protocol in this rule. Choosing a member of either the Members not in Group or the Members in Group list activates the Add and Remove buttons. Fields • Group Name—Specifies the name of the new TCP service group. Cisco ASA Series VPN ASDM Configuration Guide 4-41 Chapter 4 General VPN Setup Access Control List Manager • Description—(Optional) Provides a brief description of this group. • Members not in Group—Presents the option to select either an ICMP type/ICMP group or an ICMP number to add to the Members in Group list. • ICMP Type/ICMP Group—Selects the option to select the name of an ICMP group to add to the Members in Group list. • ICMP #—Selects the option to specify an ICMP member by number to add to the Members in Group list. • Add—Moves a selected item from the Members not in Group list to the Members in Group list. • Remove—Moves a selected item from the Members in Group list to the Members not in Group list. • Members in Group—Lists the members already configured in this service group. Browse Other ACL Manager > Add/Edit Extended Access List Rule > Protocol and Service > Protocol: other >Other > Group option > Browse button The Browse Other dialog box lets you select a protocol group for this rule. Fields • Add—Opens the Add Protocol Group dialog box, in which you can configure a new service group. • Find—Opens the Filter field. • Filter/Clear—Specifies a filter criterion that you can use to search for items in the Name list, thus displaying only those items that match that criterion. When you make an entry in the Filter field, the Filter button becomes active. Clicking the Filter button performs the search. After you perform the search, the Filter button is dimmed, and the Clear button becomes active. Clicking the Clear button clears the filter field and dims the Clear button. • Type—Determines the type of object to use as the protocol group for this rule. Selections are IP Address Objects, IP Names, Network Object Groups, and All. The contents of the table following this field change, depending upon your selection. • Name—Lists the predefined protocol groups for your selection. Add Protocol Group ACL Manager > Add/Edit Extended Access List Rule > Protocol and Service > Protocol: other > Group option > Browse button > Browse Other > Add button The Add Protocol Group dialog box lets you configure a new a protocol group by name or by number to add to the browsable protocol list for this rule. Selecting a member of either the Members not in Group or the Members in Group list activates the Add and Remove buttons. Fields • Group Name—Specifies the name of the new TCP service group. • Description—(Optional) Provides a brief description of this group. • Members not in Group—Presents the option to select either a protocol/protocol group or a protocol number to add to the Members in Group list. • Protocol/Protocol Group—Selects the option to select the name of a protocol or protocol group to add to the Members in Group list. Cisco ASA Series VPN ASDM Configuration Guide 4-42 Chapter 4 General VPN Setup Access Control List Manager • Protocol #—Selects the option to specify a protocol by number to add to the Members in Group list. • Add—Moves a selected item from the Members not in Group list to the Members in Group list. • Remove—Moves a selected item from the Members in Group list to the Members not in Group list. • Members in Group—Lists the members already configured in this service group. Client Firewall with Local Printer and Tethered Device Support When users connect to the ASA, all traffic is tunneled through the connection and users cannot access resources on their local network. This includes printers, cameras, and Windows Mobile devices (tethered devices) that synchronize with the local computer. Enabling Local LAN Access in the client profile resolves this problem, however it can introduce a security or policy concern for some enterprises as a result of unrestricted access to the local network. You can use the ASA to deploy endpoint OS firewall capabilities to restrict access to particular types of local resources, such as printers and tethered devices. To do so, enable client firewall rules for specific ports for printing. The client distinguishes between inbound and outbound rules. For printing capabilities, the client opens ports required for outbound connections, but blocks all incoming traffic. Note Be aware that users logged in as administrators have the ability to modify the firewall rules deployed to the client by the ASA. Users with limited privileges cannot modify the rules. For either user, the client reapplies the firewall rules when the connection terminates. If you configure the client firewall, and the user authenticates to an Active Directory (AD) server, the client still applies the firewall policies from the ASA. However, the rules defined in the AD group policy take precedence over the rules of the client firewall. The following sections describe procedures on how to do this: • Deploying a Client Firewall for Local Printer Support, page 4-44 • Tethered Devices Support, page 4-45 Usage Notes about Firewall Behavior The following notes clarify how the AnyConnect client uses the firewall: • The source IP is not used for firewall rules. The client ignores the source IP information in the firewall rules sent from the ASA. The client determines the source IP depending on whether the rules are public or private. Public rules are applied to all interfaces on the client. Private rules are applied to the Virtual Adapter. • The ASA supports many protocols for ACL rules. However, the AnyConnect firewall feature supports only TCP, UDP, ICMP, and IP. If the client receives a rule with a different protocol, it treats it as an invalid firewall rule, and then disables split tunneling and uses full tunneling for security reasons. • Starting in ASA 9.0, the Public Network Rule and Private Network Rule support unified access control lists. These access control lists can be used to define IPv4 and IPv6 traffic in the same rule. Be aware of the following differences in behavior for each operating system: • For Windows computers, deny rules take precedence over allow rules in Windows Firewall. If the ASA pushes down an allow rule to the AnyConnect client, but the user has created a custom deny rule, the AnyConnect rule is not enforced. Cisco ASA Series VPN ASDM Configuration Guide 4-43 Chapter 4 General VPN Setup Access Control List Manager • On Windows Vista, when a firewall rule is created, Vista takes the port number range as a comma-separated string. The port range can be a maximum of 300 ports. For example, from 1-300 or 5000-5300. If you specify a range greater than 300 ports, the firewall rule is applied only to the first 300 ports. • Windows users whose firewall service must be started by the AnyConnect client (not started automatically by the system) may experience a noticeable increase in the time it takes to establish a VPN connection. • On Mac computers, the AnyConnect client applies rules sequentially in the same order the ASA applies them. Global rules should always be last. • For third-party firewalls, traffic is passed only if both the AnyConnect client firewall and the third-party firewall allow that traffic type. If the third-party firewall blocks a specific traffic type that the AnyConnect client allows, the client blocks the traffic. Deploying a Client Firewall for Local Printer Support The ASA supports the AnyConnect client firewall feature with ASA version 8.3(1) or later, and ASDM version 6.3(1) or later. This section describes how to configure the client firewall to allow access to local printers, and how to configure the client profile to use the firewall when the VPN connection fails. Limitations and Restrictions of the Client Firewall The following limitations and restrictions apply to using the client firewall to restrict local LAN access: • Due to limitations of the OS, the client firewall policy on computers running Windows XP is enforced for inbound traffic only. Outbound rules and bidirectional rules are ignored. This would include firewall rules such as 'permit ip any any'. • Host Scan and some third-party firewalls can interfere with the firewall. The following table clarifies what direction of traffic is affected by the source and destination port settings: Source Port Destination Port Traffic Direction Affected Specific port number Specific port number Inbound and outbound A range or 'All' (value of 0) A range or 'All' (value of 0) Inbound and outbound Specific port number A range or 'All' (value of 0) Inbound only A range or 'All' (value of 0) Specific port number Outbound only Example ACL Rules for Local Printing The ACL AnyConnect_Client_Local_Print is provided with ASDM to make it easy to configure the client firewall. When you select that ACL for Public Network Rule in the Client Firewall pane of a group policy, that list contains the following ACEs: . Table 4-1 ACL Rules in AnyConnect_Client_Local_Print Description Permission Interface Protocol Source Port Destination Address Destination Port Deny all Deny Public Any Default1 Any Default LPD Allow Public TCP Default Any 515 IPP Allow Public TCP Default Any 631 Cisco ASA Series VPN ASDM Configuration Guide 4-44 Chapter 4 General VPN Setup Access Control List Manager Table 4-1 ACL Rules in AnyConnect_Client_Local_Print (continued) Description Permission Interface Protocol Source Port Destination Address Destination Port Printer Allow Public TCP Default Any 9100 mDNS Allow Public UDP Default 224.0.0.251 5353 LLMNR Allow Public UDP Default 224.0.0.252 5355 NetBios Allow Public TCP Default Any 137 NetBios Allow Public UDP Default Any 137 1. The port range is 1 to 65535. Note To enable local printing, you must enable the Local LAN Access feature in the client profile with a defined ACL rule allow Any Any. Configuring Local Print Support Step 1 Enable the AnyConnect client firewall in a group policy. Go to Configuration > Remote Access VPN > Network (Client) Access > Group Policies. Step 2 Select a group policy and click Edit. The Edit Internal Group Policy window displays. Step 3 Select Advanced > AnyConnect Client > Client Firewall. Click Manage for the Private Network Rule. Step 4 Create an ACL and specify an ACE using the rules in Table 4-1. Add this ACL as a PrivateNetwork Rule. Step 5 If you enabled the Automatic VPN Policy always-on and specified a closed policy, in the event of a VPN failure, users have no access to local resources. You can apply the firewall rules in this scenario by going to Preferences (Cont) in the profile editor and checking Apply last local VPN resource rules. Tethered Devices Support To support tethered devices and protect the corporate network, create a standard ACL in the group policy, specifying destination addresses in the range that the tethered devices use. Then specify the ACL for split tunneling as a network list to exclude from tunneled VPN traffic. You must also configure the client profile to use the last VPN local resource rules in case of VPN failure. Note For Windows Mobile devices that need to sync with the computer running AnyConnect, specify the IPv4 destination address as 169.254.0.0, or the IPv6 destination address fe80::/64 in the ACL. Follow these steps: Step 1 In ASDM, go to Group Policy > Advanced > Split Tunneling. Step 2 Uncheck Inherit next to the Network List field and click Manage. The ACL Manager displays. Step 3 Click the Extended ACL tab. Step 4 Click Add and then Add ACL. Specify a name for the new ACL. Cisco ASA Series VPN ASDM Configuration Guide 4-45 Chapter 4 General VPN Setup Access Control List Manager Step 5 Choose the new ACL in the table and click Add and then Add ACE. The Edit ACE window displays. Step 6 For Action, choose the Permit radio button. Step 7 In the destination criteria area, specify the IPv4 destination address as 169.254.0.0 or the IPv6 destination address fe80::/64. Step 8 For Service, choose IP. Step 9 Click OK. Step 10 Click OK to save the ACL. Step 11 In the Split Tunneling pane for the internal group policy, uncheck Inherit for the Policy or IPv6 Policy, depending on the IP address you specified in step 7, and choose Exclude Network List Below. For Network List, choose the ACL you created. Step 12 Click OK. Step 13 Click Apply. Fields • Public Network Rule—Use the drop-down list to choose from the existing defined ACLs. Manage—Displays the ACL Manager dialog box, with which you can add, edit, and delete Access Control Lists (ACLs) and Extended Access Control Lists (ACEs). • Private Network Rule—Use the drop-down list to choose from the existing defined ACLs. Manage—Displays the ACL Manager dialog box, with which you can add, edit, and delete Access Control Lists (ACLs) and Extended Access Control Lists (ACEs). Configuring a Web ACLs Configuration > Remote Access > Clientless SSL VPN Access > Advanced > Web ACLs Configuration > Remote Access > Clientless SSL VPN Access > Group Policies > General > More Options > Web ACL This dialog box lets you configure ACLs for Clientless SSL VPN connections. Fields • View (Unlabeled)—Indicates whether the selected entry is expanded (minus sign) or contracted (plus sign). • # column—Specifies the ACE ID number. • Enable—Indicates whether this ACL is enabled or disabled. You can enable or disable the ACL using this check box. • Action—Specifies whether this ACL permits or denies access. • Type—Specifies whether this ACL applies to a URL or a TCP address/port. • Filter—Specifies the type of filter being applied. • Syslog Level (Interval)—Specifies the syslog parameters for this ACL. • Time Range—Specifies the name of the time range, if any, for this ACL. The time range can be a single interval or a series of periodic ranges. • Description—Specifies the description, if any, of the ACL. • Add ACL—Displays the Add Web Type ACL dialog box, in which you can specify an ACL ID. Cisco ASA Series VPN ASDM Configuration Guide 4-46 Chapter 4 General VPN Setup Access Control List Manager • Add ACE—Displays the Add Web Type ACE dialog box, in which you specify parameters for the named ACL. This button is active only if there are one or more entries in the Web Type ACL table. • Edit ACE/Delete—Click to edit or delete the highlighted ACL or ACE. When you delete an ACL, you also delete all of its ACEs. No warning or undelete. • Move Up/Move Down—Highlight an ACL or ACE and click these buttons to change the order of ACLs and ACEs. The ASA checks ACLs and their ACEs in priority order according to their position in the ACLs list box until it finds a match. Add/Edit Standard Access List Rule ACL Manager > Add or Edit Standard Access List Rule The Add/Edit Standard Access List Rule dialog box lets you create a new rule, or modify an existing rule. Fields • Action—Determines the action type of the new rule. Choose either Permit or Deny. – Permit—Permits all matching traffic. – Deny—Denies all matching traffic. • Host/Network IP Address—Identifies the networks by IP address. – IP address—The IP address of the host or network. – Mask—The subnet mask of the host or network • Description—(Optional) Enter a description of the access rule. Add/Edit Server and URL List Configuration > VPN > General > Group Policy > Add/Edit > Internal Group Policy > Web VPN Tab > Other Tab > Add or Edit Server and URL List The Add or Edit Server and URL List dialog box lets you add, edit, delete, and order the items in the designated URL list. Fields • List Name—Specifies the name of the list to be added or selects the name of the list to be modified or deleted. • URL Display Name—Specifies the URL name displayed to the user. • URL—Specifies the actual URL associated with the display name. • Add—Opens the Add Server or URL dialog box, in which you can configure a new server or URL and display name. • Edit—Opens the Edit Server or URL dialog box, in which you can configure a new server or URL and display name. • Delete—Removes the selected item from the server and URL list. There is no confirmation or undo. • Move Up/Move Down—Changes the position of the selected item in the server and URL list. Cisco ASA Series VPN ASDM Configuration Guide 4-47 Chapter 4 General VPN Setup Configuring AnyConnect VPN Client Connections Add/Edit Server or URL Configuration > VPN > General > Group Policy > Add/Edit > Internal Group Policy > Web VPN Tab > Other Tab > Add or Edit Server and URL The Add or Edit Server or URL dialog box lets you add or edit, delete, and order the items in the designated URL list. Fields • URL Display Name—Specifies the URL name displayed to the user. • URL—Specifies the actual URL associated with the display name. Configuring AnyConnect VPN Client Connections The Cisco AnyConnect VPN client provides secure SSL or IPsec (IKEv2) connections to the ASA for remote users. The client gives remote users the benefits of a VPN client without the need for network administrators to install and configure clients on remote computers. Without a previously-installed client, remote users enter the IP address in their browser of an interface configured to accept SSL VPN connections. Unless the ASA is configured to redirect http:// requests to https://, users must enter the URL in the form https://
. After entering the URL, the browser connects to that interface and displays the login screen. If the user satisfies the login and authentication, and the ASA identifies the user as requiring the client, it downloads the client that matches the operating system of the remote computer. After downloading, the client installs and configures itself, establishes a VPN connection and either remains or uninstalls itself (depending on the ASA configuration) when the connection terminates. In the case of a previously installed client, when the user authenticates, the ASA examines the revision of the client, and upgrades the client as necessary. The AnyConnect client can be downloaded from the ASA, or it can be installed manually on the remote PC by the system administrator. For more information about installing the client manually, see the AnyConnect Administrators Guide. The ASA downloads the client based on the group policy or username attributes of the user establishing the connection. You can configure the ASA to automatically download the client, or you can configure it to prompt the remote user about whether to download the client. In the latter case, if the user does not respond, you can configure the ASA to either download the client after a timeout period or present the login page. Fields • Keep Installer on Client System—Enable to allow permanent client installation on the remote computer. Enabling disables the automatic uninstalling feature of the client. The client remains installed on the remote computer for subsequent connections, reducing the connection time for the remote user. Note Keep Installer on Client System is not supported after version 2.5 of the AnyConnect client. • Compression—Compression increases the communications performance between the security appliance and the client by reducing the size of the packets being transferred. Cisco ASA Series VPN ASDM Configuration Guide 4-48 Chapter 4 General VPN Setup Configuring AnyConnect VPN Client Connections • Datagram TLS—Datagram Transport Layer Security avoids latency and bandwidth problems associated with some SSL connections and improves the performance of real-time applications that are sensitive to packet delays. • Ignore Don’t Defrag (DF) Bit—This feature allows the force fragmentation of packets that have the DF bit set, allowing them to pass through the tunnel. An example use case is for servers in your network that do not respond correctly to TCP MSS negotiations. • Client Bypass Protocol—The Client Protocol Bypass feature allows you to configure how the ASA manages IPv4 traffic when it is expecting only IPv6 traffic or how it manages IPv6 traffic when it is expecting only IPv4 traffic. When the AnyConnect client makes a VPN connection to the ASA, the ASA could assign it an IPv4, IPv6, or both an IPv4 and IPv6 address. If the ASA assigns the AnyConnect connection only an IPv4 address or only an IPv6 address, you can now configure the Client Bypass Protocol to drop network traffic for which the ASA did not assign an IP address, or allow that traffic to bypass the ASA and be sent from the client unencrypted or “in the clear”. For example, assume that the ASA assigns only an IPv4 address to an AnyConnect connection and the endpoint is dual stacked. When the endpoint attempts to reach an IPv6 address, if Client Bypass Protocol is disabled, the IPv6 traffic is dropped; however, if Client Bypass Protocol is enabled, the IPv6 traffic is sent from the client in the clear. • FQDN of This Device—This information is used by the client after network roaming in order to resolve the ASA IP address used for re-establishing the VPN session. This setting is critical to support roaming between networks of different IP protocols (such as IPv4 to IPv6). Note You cannot use the ASA FQDN present in the AnyConnect profile to derive the ASA IP address after roaming. The addresses may not match the correct device (the one the tunnel was established to) in the load balancing scenario. If the device FQDN is not pushed to the client, the client will try to reconnect to whatever IP address the tunnel had previously established. In order to support roaming between networks of different IP protocols (from IPv4 to IPv6), AnyConnect must perform name resolution of the device FQDN after roaming, so that it can determine which ASA address to use for re-establishing the tunnel. The client uses the ASA FQDN present in its profile during the initial connection. During subsequent session reconnects, it always uses the device FQDN pushed by ASA (and configured by the administrator in the group policy), when available. If the FQDN is not configured, the ASA derives the device FQDN (and sends it to the client) from whatever is set under Device Setup > Device Name/Password and Domain Name. If the device FQDN is not pushed by the ASA, the client cannot re-establish the VPN session after roaming between networks of different IP protocols. • MTU—Adjusts the MTU size for SSL connections. Enter a value in bytes, from 256 to 1410 bytes. By default, the MTU size is adjusted automatically based on the MTU of the interface that the connection uses, minus the IP/UDP/DTLS overhead. • Keepalive Messages—Enter a number, from 15 to 600 seconds, in the Interval field to enable and adjust the interval of keepalive messages to ensure that an connection through a proxy, firewall, or NAT device remains open, even if the device limits the time that the connection can be idle. Adjusting the interval also ensures that the client does not disconnect and reconnect when the remote user is not actively running a socket-based application, such as Microsoft Outlook or Microsoft Internet Explorer. Cisco ASA Series VPN ASDM Configuration Guide 4-49 Chapter 4 General VPN Setup Configuring AnyConnect VPN Client Connections • Optional Client Modules to Download—To minimize download time, the AnyConnect client requests downloads (from the ASA) only of modules that it needs for each feature that it supports. You must specify the names of modules that enable other features. The AnyConnect client, version 3.0, includes the following modules (previous versions have fewer modules): – AnyConnect DART—The Diagnostic AnyConnect Reporting Tool (DART) captures a snapshot of system logs and other diagnostic information and creates a .zip file on your desktop so you can conveniently send troubleshooting information to Cisco TAC. – AnyConnect Network Access Manager—Formerly called the Cisco Secure Services Client, this module provides 802.1X (Layer 2) and device authentication for access to both wired and wireless network is integrated into AnyConnect 3.0. – AnyConnect SBL—Start Before Logon (SBL) forces the user to connect to the enterprise infrastructure over a VPN connection before logging on to Windows by starting AnyConnect before the Windows login dialog box appears. – AnyConnect Web Security Module—Formerly called ScanSafe Hostscan, this module is integrated into the AnyConnect 3.0. – AnyConnect Telemetry Module—Sends information about the origin of malicious content to the web filtering infrastructure of the Cisco IronPort Web Security Appliance (WSA), which uses this data to provide better URL filtering rules. – AnyConnect Posture Module—Formerly called the Cisco Secure Desktop HostScan feature, the posture module is integrated into AnyConnect 3.0 and provides AnyConnect the ability to gather credentials for posture assessment prior to creating a remote access connection to the ASA. • Always-On VPN—Determine if the always-on VPN flag setting in the AnyConnect service profile is disabled or if the AnyConnect service profile setting should be used. The always-on VPN feature lets AnyConnnect automatically establish a VPN session after the user logs onto a computer. The VPN session remains up until the user logs off the computer. If the physical connection is lost, the session remains up, and AnyConnect continually attempts to reestablish the physical connection with the adaptive security appliance to resume the VPN session. Always-on VPN permits the enforcement of corporate policies to protect the device from security threats. You can use it to help ensure AnyConnect establishes a VPN session whenever the endpoint is not in a trusted network. If enabled, a policy is configured to determine how network connectivity is managed in the absence of a connection. Note • Always-On VPN requires an AnyConnect release that supports AnyConnect Secure Mobility features. Refer to the Cisco AnyConnect VPN Client Administrator Guide for additional information. Client Profiles to Download—A profile is a group of configuration parameters that the AnyConnect client uses to configure VPN, Network Access Manager, web security, and telemetry settings. Click Add to launch the Select Anyconnect Client Profiles window where you can specify previously-created profiles for this group policy. Cisco ASA Series VPN ASDM Configuration Guide 4-50 Chapter 4 General VPN Setup Configuring AnyConnect VPN Client Connections Using AnyConnect Client Profiles You enable Cisco AnyConnect Secure Mobility client features in the AnyConnect profiles—XML files that contain configuration settings for the core client with its VPN functionality and for the optional client modules Network Access Manager, telemetry, and web security. The ASA deploys the profiles during AnyConnect installation and updates. Users cannot manage or modify profiles. You can configure a profile using the AnyConnect profile editor, a convenient GUI-based configuration tool launched from ASDM. The AnyConnect software package, version 2.5 and later (for all OSs), includes the editor, which activates when you load the AnyConnect package on the ASA as an AnyConnect client image. Alternatively, you can manually edit the XML file and import the file to the ASA as a profile. You can configure the ASA to deploy profiles globally for all AnyConnect users or to users based on their group policy. Usually, a user has a single profile file for each AnyConnect module installed. In some cases, you might want to provide more than one profile for a user. Someone who works from multiple locations might need more than one profile. Be aware that some of the profile settings (such as SBL) control the connection experience at a global level. Other settings are unique to a particular host and depend on the host selected. Some profile settings are stored locally on the user computer in a user preferences file or a global preferences file. The user file has information the client needs to display user-controllable settings in the Preferences tab of the client GUI and information about the last connection, such as the user, the group, and the host. The global file has information about user-controllable settings to be able to apply those settings before login (since there is no user). For example, the client needs to know if Start Before Logon and/or AutoConnect On Start are enabled before login. For more information about creating and deploying AnyConnect client profiles and controlling client features, see the AnyConnect VPN Client Administrator Guide. Fields Add—Displays the Add AnyConnect Client Profiles dialog box, where you can specify a file in flash memory as a profile, or where you can browse flash memory for a file to specify as a profile. You can also upload a file from a local computer to the flash memory. Edit—Displays the Edit SSL VPN Client Profile window, where you can change the settings contained in the profile for AnyConnect client features. Delete—Deletes a profile from the table. This does not delete the XML file from flash. AnyConnect Client Profiles Table—Displays the XML files specified as AnyConnect client profiles: • Profile Name—The name of the profile specified when the profile was added. • Profile Usage/Type—Displays the use for this profile, such as VPN, Network Access Manager, or telemetry. Specifying an AnyConnect Client Profile Specify an AnyConnect client profile for this group policy. For more information about creating and deploying AnyConnect client profiles and controlling client features, see the AnyConnect VPN Client Administrator Guide. Fields Profile Name—Specify an AnyConnect client profile for this group policy. Cisco ASA Series VPN ASDM Configuration Guide 4-51 Chapter 4 General VPN Setup Configuring AnyConnect VPN Client Connections Profile Usage—Displays the usage assigned to the profile when originally created: VPN, Network Access Manager, web security, or telemetry. If ASDM does not recognize the usage specified in the XML file, the drop-down list becomes selectable and you can choose a usage type manually. Profile Location—Specify a path to the profile file in the ASA flash memory. If the file does not exist, the ASA creates one based on the profile template. Importing an AnyConnect Client Profile Import a new AnyConnect client profile in this window. You can import a profile from a local device or a remote server. For more information about creating and deploying AnyConnect client profiles and controlling client features, see the AnyConnect VPN Client Administrator Guide. Fields Profile Name—Specify a name for the profile you add. Profile Usage—Displays the usage assigned to the profile when originally created: VPN, Network Access Manager, web security, or telemetry. If ASDM does not recognize the usage specified in the XML file, the drop-down list becomes selectable and you can choose a usage type manually. Group Policy—Specify a group policy for this profile. The profile downloads to users belonging to the group policy along with the AnyConnect client. Profile Location—Specify a path to the profile file in the ASA flash memory. If the file does not exist, the ASA creates one based on the profile template. Exporting an AnyConnect Client Profile Export an AnyConnect VPN client profile from this window. You can export to a local device or a remote server. For more information about creating and deploying AnyConnect client profiles and controlling client features, see the AnyConnect VPN Client Administrator Guide. Fields Device Profile Path—Displays the path and filename of the profile file. Local Path—Specify the path and filename to export the profile file. Browse Local—Click to launch a window to browse the local device file system. Exempting AnyConnect Traffic from Network Address Translation If you have configured your ASA to perform network address translation (NAT), you must exempt your remote access AnyConnect client traffic from being translated so that the AnyConnect clients, internal networks, and corporate resources on a DMZ, can originate network connections to each other. Failing to exempt the AnyConnect client traffic from being translated prevents the AnyConnect clients and other corporate resources from communicating. “Identity NAT” (also known as “NAT exemption”) allows an address to be translated to itself, which effectively bypasses NAT. Identity NAT can be applied between two address pools, an address pool and a subnetwork, or two subnetworks. Cisco ASA Series VPN ASDM Configuration Guide 4-52 Chapter 4 General VPN Setup Configuring AnyConnect VPN Client Connections This procedure illustrates how you would configure identity NAT between these hypothetical network objects in our example network topology: Engineering VPN address pool, Sales VPN address pool, inside network, a DMZ network, and the Internet. Each Identity NAT configuration requires one NAT rule. Table 4-2 Network Addressing for Configuring Identity NAT for VPN Clients Network or Address Pool Network or address pool name Range of addresses Inside network inside-network 10.50.50.0 - 10.50.50.255 Engineering VPN address pool Engineering-VPN 10.60.60.1 - 10.60.60.254 Sales VPN address pool Sales-VPN 10.70.70.1 - 10.70.70.254 DMZ network DMZ-network 192.168.1.0 - 192.168.1.255 Step 1 Log into the ASDM and select Configuration > Firewall > NAT Rules. Step 2 Create a NAT rule so that the hosts in the Engineering VPN address pool can reach the hosts in the Sales VPN address pool. In the NAT Rules pane, select Add > Add NAT Rule Before “Network Object” NAT rules so that the ASA evaluates this rule before other rules in the Unified NAT table. See Figure 4-2 on page 4-53 for an example of the Add NAT rule dialog box. Note NAT rule evaluation is applied on a top-down, first match basis. Once the ASA matches a packet to a particular NAT rule it does not perform any further evaluation. It is important that you place the most specific NAT rules at the top of the Unified NAT table so that the ASA does not prematurely match them to broader NAT rules. Figure 4-2 a. Add NAT rule dialog box In the Match criteria: Original Packet area, configure these fields: Cisco ASA Series VPN ASDM Configuration Guide 4-53 Chapter 4 General VPN Setup Configuring AnyConnect VPN Client Connections – Source Interface: Any – Destination Interface: Any – Source Address: Click the Source Address browse button and create the network object that represents the Engineering VPN address pool. Define the object type as a Range of addresses. Do not add an automatic address translation rule. See Figure 4-3 for an example. – Destination Address: Click the Destination Address browse button and create the network object that represents the Sales VPN address pool. Define the object type as a Range of addresses. Do not add an automatic address translation rule. Figure 4-3 b. Create Network Object for a VPN address pool In the Action Translated Packet area, configure these fields: – Source NAT Type: Static – Source Address: Original – Destination Address: Original – Service: Original c. In the Options area, configure these fields: – Check Enable rule. – Uncheck or leave empty the Translate DNS replies that match this rule. – Direction: Both – Description: Add a Description for this rule. d. Click OK. e. Click Apply. Your rule should look like rule 1 in the Unified NAT table in Figure 4-5 on page 4-57. CLI example: nat source static Engineering-VPN Engineering-VPN destination static Sales-VPN Sales-VPN f. Click Send. Cisco ASA Series VPN ASDM Configuration Guide 4-54 Chapter 4 General VPN Setup Configuring AnyConnect VPN Client Connections Step 3 When ASA is performing NAT, in order for two hosts in the same VPN pool to connect to each other, or for those hosts to reach the Internet through the VPN tunnel, you must enable the Enable traffic between two or more hosts connected to the same interface option. To do this, in ASDM, select Configuration > Device Setup > Interfaces. At the bottom of the Interface panel, check Enable traffic between two or more hosts connected to the same interface and click Apply. CLI example: same-security-traffic permit inter-interface Step 4 Create a NAT rule so that the hosts in the Engineering VPN address pool can reach other hosts in the Engineering VPN address pool. Create this rule just as you created the rule in Step 2 except that you specify the Engineering VPN address pool as both the Source address and the Destination Address in the Match criteria: Original Packet area. Step 5 Create a NAT rule so that the Engineering VPN remote access clients can reach the “inside” network. In the NAT Rules pane, select Add > Add NAT Rule Before “Network Object” NAT rules so that this rule will be processed before other rules. a. In the Match criteria: Original Packet area configure these fields: – Source Interface: Any – Destination Interface: Any – Source Address: Click the Source Address browse button and create a network object that represents the inside network. Define the object type as a Network of addresses. Do not add an automatic address translation rule. – Destination Address: Click the Destination Address browse button and select the network object that represents the Engineering VPN address pool. Figure 4-4 b. Add inside-network object In the Action: Translated Packet area, configure these fields: – Source NAT Type: Static – Source Address: Original – Destination Address: Original Cisco ASA Series VPN ASDM Configuration Guide 4-55 Chapter 4 General VPN Setup Configuring AnyConnect VPN Client Connections – Service: Original c. In the Options area, configure these fields: – Check Enable rule. – Uncheck or leave empty the Translate DNS replies that match this rule. – Direction: Both – Description: Add a Description for this rule. d. Click OK. e. Click Apply. Your rule should look like rule two in the Unified NAT table in Figure 4-5 on page 4-57. CLI example nat source static inside-network inside-network destination static Engineering-VPN Engineering-VPN Step 6 Create a new rule, following the method in Step 5, to configure identity NAT for the connection between the Engineering VPN address pool and the DMZ network. Use the DMZ network as the Source Address and use the Engineering VPN address pool as the Destination address. Step 7 Create a new NAT rule to allow the Engineering VPN address pool to access the Internet through the tunnel. In this case, you do not want to use identity NAT because you want to change the source address from a private address to an Internet routable address. To create this rule, follow this procedure: a. In the NAT Rules pane, select Add > Add NAT Rule Before “Network Object” NAT rules so that this rule will be processed before other rules. b. In the Match criteria: Original Packet area configure these fields: – Source Interface: Any – Destination Interface: Any. This field will be automatically populated with “outside” after you select outside as the Source Address in the Action: Translated Packet area. – Source Address: Click the Source Address browse button and select the network object that represents the Engineering VPN address pool. – Destination Address: Any. c. In the Action: Translated Packet area, configure these fields: – Source NAT Type: Dynamic PAT (Hide) – Source Address: Click the Source Address browse button and select the outside interface. – Destination Address: Original – Service: Original d. In the Options area, configure these fields: – Check Enable rule. – Uncheck or leave empty the Translate DNS replies that match this rule. – Direction: Both – Description: Add a Description for this rule. e. Click OK. f. Click Apply. Your rule should look like rule five in the Unified NAT table in Figure 4-5 on page 4-57. Cisco ASA Series VPN ASDM Configuration Guide 4-56 Chapter 4 General VPN Setup Configuring AnyConnect VPN Connections CLI example: nat (any,outside) source dynamic Engineering-VPN interface Figure 4-5 Unified NAT table Step 8 After you have configured the Engineering VPN Address pool to reach itself, the Sales VPN address pool, the inside network, the DMZ network, and the Internet; you must repeat this process for the Sales VPN address pool. Use identity NAT to exempt the Sales VPN address pool traffic from undergoing network address translation between itself, the inside network, the DMZ network, and the Internet. Step 9 From the File menu on the ASA, select Save Running Configuration to Flash to implement your identity NAT rules. Configuring AnyConnect VPN Connections Use the AnyConnect Connection Profiles pane and its child dialog boxes to specify VPN connection attributes for client-based connections. These attributes apply to the Cisco AnyConnect VPN client and to the legacy SSL VPN client. The initial client deployment requires end-user administrative rights. The Cisco AnyConnect VPN client supports the HTTPS/TCP (SSL) and Datagram Transport Layer Security (DTLS) tunneling options. In the main pane, you can enable client access on the interfaces you select and you can select, add, edit, and delete connections (tunnel groups). You can also specify whether you want to allow a user to select a particular connection at login. Fields • Access Interfaces—Lets you select from a table the interfaces on which to enable access. The fields in this table include the interface name and check boxes specifying whether to allow access. – In the Interface table, in the row for the interface you are configuring for AnyConnect connections, check the protocols you want to enable on the interface. You can allow SSL Access, IPsec access, or both. Cisco ASA Series VPN ASDM Configuration Guide 4-57 Chapter 4 General VPN Setup Configuring AnyConnect VPN Connections When checking SSL, DTLS (Datagram Transport Layer Security) is enabled by default. DTLS avoids latency and bandwidth problems associated with some SSL connections and improves the performance of real-time applications that are sensitive to packet delays. When checking IPsec (IKEv2) access, client services are enabled by default. Client services include enhanced Anyconnect features including software updates, client profiles, GUI localization (translation) and customization, Cisco Secure Desktop, and SCEP proxy. If you disable client services, the AnyConnect client still establishes basic IPsec connections with IKEv2. – Device Certificate—Lets you specify a certificate for authentication for either an RSA key or an ECDSA key. See Specifying a Device Certificate, page 4-58. – Port Setting—Configure port numbers for clientless SSL and IPsec (IKEv2) connections. See Configuring Port Settings, page 4-59. – Enable inbound VPN sessions to bypass interface ACLs is checked by default.— The security appliance allows all VPN traffic to pass through the interface ACLs. For example, even if the outside interface ACL does not permit the decrypted traffic to pass through, the security appliance trusts the remote private network and permits the decrypted packets to pass through. You can change this default behavior. If you want the interface ACL to inspect the VPN protected traffic, uncheck this box. • Login Page Setting – Allow the user to select a connection profile, identified by its alias, on the login page. If you do not check this check box, the default connection profile is DefaultWebVPNGroup. – Shutdown portal login page.—Shows the web page when the login is disabled. • Connection Profiles—Configure protocol-specific attributes for connections (tunnel groups). – Add/Edit—Click to Add or Edit a Connection Profile (tunnel group). – Name—The name of the Connection Profile. – Aliases—Other names by which the Connection Profile is known. – SSL VPN Client Protocol—Specifies whether SSL VPN client have access. – Group Policy—Shows the default group policy for this Connection Profile. – Allow user to select connection, identified by alias in the table above, at login page—Check to enable the display of Connection Profile (tunnel group) aliases on the Login page. • Let group URL take precedence if group URL and certificate map match different connection profiles. Otherwise, the connection profile matches the certificate map will be used.—This option specifies the relative preference of the group URL and certificate values during the connection profile selection process. If the ASA fails to match the preferred value, it chooses the connection profile that matches the other value. Check this option only if you want to rely on the preference used by many older ASA software releases to match the group URL specified by the VPN endpoint to the connection profile that specifies the same group URL. This option is unchecked by default. If it is unchecked, the ASA prefers to match the certificate field value specified in the connection profile to the field value of the certificate used by the endpoint to assign the connection profile. Specifying a Device Certificate The Specify Device Certificate screen allows you to specify a certificate that will identify the ASA to the client when it attempts to create a connection. This screen is for AnyConnect Connection Profiles and Clientless Connection Profiles. Cisco ASA Series VPN ASDM Configuration Guide 4-58 Chapter 4 General VPN Setup Configuring AnyConnect VPN Connections For VPN connections (not clientless): • Certain AnyConnect features, such as Always-on IPsec/IKEv2, require that a valid and trusted device certificate be available on the ASA. • If your AnyConnect clients are configured to use only SSL, then you only need to specify an RSA certificate as AnyConnect does not support ECDSA certificates for SSL VPN. If your AnyConnect clients are configured to use IPsec or SSL, or both IPsec and SSL, you can configure both kinds of certificates. • ECDSA certificates are only supported on IPsec connections. Detailed Steps Step 1 Step 2 (For VPN connections only) In the Certificate with RSA Key area, perform one of these tasks: • Keep the Use the same device certificate for SSL and IPsec IKEv2 box checked if you want to choose one certificate to authenticate clients using either protocol. You can select the certificate from those available in the list box or click Manage to create an identity certificate to use. • Uncheck the Use the same device certificate for SSL and IPsec IKEv2 check box to specify separate certificates for SSL connections or IPsec connections. Select a certificate from the Device Certficate list box. If you do not see the certificate you want, click the Manage button to manage the identity certficiates on the ASA. Step 3 (For VPN connections only) In the Certificate with ECDSA key field, select the ECDSA certificate from the list box or click Manage to create an ECDSA identity certificate. Step 4 Click OK. Configuring Port Settings Configure port numbers for SSL and IPsec (IKEv2) connections in this window: Fields • SSL Ports: – HTTPS Port—The port to enable HTTPS for clientless (browser-based) SSL connections. The range is 1-65535. The default is port 443. – DTLS Port—The port to enable DTLS for SSL connections. The range is 1-65535. The default is port 443. • IPsec Client Services Port—The port to enable client services for IKEv2 connections. The range is 1-65535. The default is port 443. Setting the Basic Attributes for an AnyConnect VPN Connection To set the basic attributes for an AnyConnect VPN connection, choose Add or Edit in the Anyconnect Connection Profiles section. The Add (or Edit) Anyconnect Connection Profile > Basic dialog box opens. Cisco ASA Series VPN ASDM Configuration Guide 4-59 Chapter 4 General VPN Setup Configuring AnyConnect VPN Connections Fields Set the attributes in the Add AnyConnect Connection Profile > Basic dialog box as follows: • Name—For Add, specify the name of the connection profile you are adding. For Edit, this field is not editable. • Aliases—(Optional) Enter one or more alternative names for the connection. You can spaces or punctuation to separate the names. • Authentication—Choose one of the following methods to use to authenticate the connection and specify a AAA server group to use in authentication. – AAA, Certificate, or Both—Select the type of authentication to use: AAA, Certificate, or Both. If you choose either Certificate or Both, the user must provide a certificate in order to connect. – AAA Server Group—Choose a AAA server group from the drop-down list. The default setting is LOCAL, which specifies that the ASA handles the authentication. Before making a selection, you can click Manage to open a dialog box over this dialog box to view or make changes to the ASA configuration of AAA server groups. – Choosing something other than LOCAL makes available the Use LOCAL if Server Group Fails check box. – Use LOCAL if Server Group fails—Check to enable the use of the LOCAL database if the group specified by the Authentication Server Group attribute fails. • Client Address Assignment—Select the DHCP servers, client address pools, and client IPv6 address pools to use. – DHCP Servers—Enter the name or IP address of a DHCP server to use. – Client Address Pools—Enter pool name of an available, configured pool of IPv4 addresses to use for client address assignment. Before making a selection, you can click Select to open a dialog box over this dialog box to view or make changes to the address pools. See Configuring Local IP Address Pools, page 5-3 for more information on adding or editing an IPv4 address pool. – Client IPv6 Address Pools—Enter the pool name of an available, configured pool of IPv6 addresses to use for client address assignment. Before making a selection, you can click Select to open a dialog box over this dialog box to view or make changes to the address pools. See Configuring Local IP Address Pools, page 5-3 for more information on adding or editing an IPv6 address pool. • Default Group Policy—Select the group policy to use. – Group Policy—Select the VPN group policy that you want to assign as the default group policy for this connection. A VPN group policy is a collection of user-oriented attribute-value pairs that can be stored internally on the device or externally on a RADIUS server. The default value is DfltGrpPolicy. You can click Manage to open a dialog box over this one to make changes to the group policy configuration. – Enable SSL VPN client protocol—Check to enable SSL for this VPN connection. – Enable IPsec (IKEv2) client protocol—Check to enable IPsec using IKEv2 for this connection. – DNS Servers—Enter the IP address(s) of DNS servers for this policy. – WINS Servers—Enter the IP address(s) of WINS servers for this policy. – Domain Name—Enter a default domain name. • Find—Enter a GUI label or a CLI command to use as a search string, then click Next or Previous to begin the search. Cisco ASA Series VPN ASDM Configuration Guide 4-60 Chapter 4 General VPN Setup Configuring AnyConnect VPN Connections Setting Advanced Attributes for a Connection Profile The Advanced menu items and their dialog boxes let you configure the following characteristics for this connection: Note • General attributes • Client Addressing attributes • Authentication attributes • Authorization attributes • Accounting attributes • Name server attributes • Clientless SSL VPN attributes SSL VPN and secondary authentication attributes apply only to SSL VPN connection profiles. Setting General Attributes for an AnyConnect SSL VPN Connection Configure the General attributes to specify the password management parameters. Fields Set the Advanced General attributes as follows: • Enable Simple Certificate Enrollment (SCEP) for this Connection Profile • Strip the realm from username before passing it on to the AAA server • Strip the group from username before passing it on to the AAA server • Group Delimiter—Changing the group delimiter value makes the change globally on all other remote connection profiles. • Enable Password Management—Lets you configure parameters relevant to overriding an account-disabled indication from a AAA server and to notifying users about password expiration. The ASA supports password management for the RADIUS and LDAP protocols. It supports the “password-expire-in-days” option only for LDAP. This parameter is valid for AAA servers that support such notification. The ASA ignores this command if RADIUS or LDAP authentication has not been configured. You can configure password management for IPsec remote access and SSL VPN tunnel-groups. Note Some RADIUS servers that support MS-CHAP currently do not support MS-CHAPv2. This feature requires MS-CHAPv2, so please check with your vendor. The ASA, releases 7.1 and later, generally supports password management for the following connection types when authenticating with LDAP or with any RADIUS configuration that supports MS-CHAPv2: – AnyConnect VPN client – IPsec VPN client – Clientless SSL VPN Cisco ASA Series VPN ASDM Configuration Guide 4-61 Chapter 4 General VPN Setup Configuring AnyConnect VPN Connections Password management is not supported for any of these connection types for Kerberos/Active Directory (Windows password) or NT 4.0 Domain. The RADIUS server (for example, Cisco ACS) could proxy the authentication request to another authentication server. However, from the ASA perspective, it is talking only to a RADIUS server. Note For LDAP, the method to change a password is proprietary for the different LDAP servers on the market. Currently, the ASA implements the proprietary password management logic only for Microsoft Active Directory and Sun LDAP servers. Native LDAP requires an SSL connection. You must enable LDAP over SSL before attempting to do password management for LDAP. By default, LDAP uses port 636. Note Allowing override account-disabled is a potential security risk. – Notify user __ days prior to password expiration—Specifies that ASDM must notify the user at login a specific number of days before the password expires. The default is to notify the user 14 days prior to password expiration and every day thereafter until the user changes the password. The range is 1 through 180 days. – Notify user on the day password expires—Notifies the user only on the day that the password expires. In either case, and, if the password expires without being changed, the ASA offers the user the opportunity to change the password. If the current password has not expired, the user can still log in using that password. Note This does not change the number of days before the password expires, but rather, it enables the notification. If you select this option, you must also specify the number of days. – Override account-disabled indication from AAA server—Overrides an account-disabled indication from a AAA server. • Translate Assigned IP Address to Public IP Address—In rare situations, you might want to use a VPN peer’s real IP address on the inside network instead of an assigned local IP address. Normally with VPN, the peer is given an assigned local IP address to access the inside network. However, you might want to translate the local IP address back to the peer’s real public IP address if, for example, your inside servers and network security is based on the peer’s real IP address. You can enable this feature on one interface per tunnel group. – Enable the address translation on interface—Enables the address translation and allows you to choose which interface the address appears on. Outside is the interface to which the AnyConnect client connects, and inside is the interface specific to the new tunnel group. Note • Because of routing issues and other limitations, we do not recommend using this feature unless you know you need it. Find—Enter a GUI label or a CLI command to use as a search string, then click Next or Previous to begin the search. Cisco ASA Series VPN ASDM Configuration Guide 4-62 Chapter 4 General VPN Setup Configuring AnyConnect VPN Connections Setting Client Addressing Attributes for an AnyConnect SSL VPN Connection The Client Addressing attributes let you configure interface-specific address pools that your connection can use. Click Add to add a new address pool or Edit to modify an existing pool. The Select Address Pools dialog box opens, showing a table listing the pool name, starting and ending address (or number of addresses), and subnet mask/prefix length of any existing pools. For a complete description of Client Addressing see Configuring Client Addressing, page 4-92. Configuring Authentication Attributes for a Connection Profile • Interface-specific Authentication Server Groups—Manages the assignment of authentication server groups to specific interfaces. – Add or Edit—Opens the Assign Authentication Server Group to Interface dialog box, in which you can specify the interface and server group, and specify whether to allow fallback to the LOCAL database if the selected server group fails. The Manage button on this dialog box opens the Configure AAA Server Groups dialog box. Your selections appear in the Interface/Server Group table. – Delete—Removes the selected server group from the table. There is no confirmation or undo. • Username Mapping from Certificate—Lets you specify the methods and fields in a digital certificate from which to extract the username. – Pre-fill Username from Certificate—Extracts the username from the specified certificate field and uses it for username/password authentication and authorization, according to the options that follow in this panel. – Hide username from end user—Specifies to not display the extracted username to the end user. – Use script to select username—Specify the name of a script to use to select a username from a digital certificate. The default is --None--. – Add or Edit—Opens the Add or Edit Script Content dialog box, in which you can define a script to use in mapping the username from the certificate. – Delete—Deletes the selected script. There is no confirmation or undo. – Use the entire DN as the username—Specifies that you want to use the entire Distinguished Name field of the certificate as the username. – Specify the certificate fields to be used as the username—Specifies one or more fields to combine into the username. Possible values for primary and secondary attributes include the following: Attribute Definition C Country: the two-letter country abbreviation. These codes conform to ISO 3166 country abbreviations. CN Common Name: the name of a person, system, or other entity. Not available a s a secondary attribute. DNQ Domain Name Qualifier. EA E-mail address. GENQ Generational Qualifier. GN Given Name. Cisco ASA Series VPN ASDM Configuration Guide 4-63 Chapter 4 General VPN Setup Configuring AnyConnect VPN Connections Attribute Definition I Initials. L Locality: the city or town where the organization is located. N Name. O Organization: the name of the company, institution, agency, association or other entity. OU Organizational Unit: the subgroup within the organization (O). SER Serial Number. SN Surname. SP State/Province: the state or province where the organization is located T Title. UID User Identifier. UPN User Principal Name. – Primary Field—Selects the first field to use from the certificate for the username. If this value is found, the secondary field is ignored. – Secondary Field—Selects the field to us if the primary field is not found. • Find—Enter a GUI label or a CLI command to use as a search string, then click Next or Previous to begin the search. Configuring Secondary Authentication Attributes for an SSL VPN Connection Profile The Secondary Authentication dialog box lets you configure secondary or “double” authentication for this connection profile. With double authentication enabled, the end user must present two sets of valid authentication credentials in order to log on. You can use secondary authentication in conjunction with pre-filling the username from a certificate. The fields in this dialog box are similar to those you configure for primary authentication, but these fields relate only to secondary authentication. When double authentication is enabled, these attributes select one or more fields in a certificate to use as the username. Configuring the secondary username from certificate attribute forces the security appliance to use the specified certificate field as the second username for the second username/password authentication. Note If you also specify the secondary authentication server group, along with the secondary username from certificate, only the primary username is used for authentication. Fields • Secondary Authorization Server Group—Specifies an authorization server group from which to extract secondary credentials. – Server Group—Select an authorization server group to use as the secondary server AAA group. The default is none. The secondary server group cannot be an SDI server group. – Manage—Opens the Configure AAA Server Groups dialog box. Cisco ASA Series VPN ASDM Configuration Guide 4-64 Chapter 4 General VPN Setup Configuring AnyConnect VPN Connections – Use LOCAL if Server Group fails—Specifies to fall back to the LOCAL database if the specified server group fails. – Use primary username—Specifies that the login dialog must request only one username. – Attributes Server—Select whether this is the primary or secondary attributes server. Note If you also specify an authorization server for this connection profile, the authorization server settings take precedence—the ASA ignores this secondary authentication server. – Session Username Server—Select whether this is the primary or secondary session username server. • Interface-Specific Authorization Server Groups—Manages the assignment of authorization server groups to specific interfaces. – Add or Edit—Opens the Assign Authentication Server Group to Interface dialog box, in which you can specify the interface and server group, and specify whether to allow fallback to the LOCAL database if the selected server group fails. The Manage button on this dialog box opens the Configure AAA Server Groups dialog box. Your selections appear in the Interface/Server Group table. – Delete—Removes the selected server group from the table. There is no confirmation or undo. • Username Mapping from Certificate—Specify the fields in a digital certificate from which to extract the username. • Pre-fill Username from Certificate—Check to extract the names to be used for secondary authentication from the primary and secondary fields specified in this panel. You must configure the authentication method for both AAA and certificates before checking this attribute. To do so, return to the Basic panel in the same window and check Both next to Method. • Hide username from end user—Check to hide the username to be used for secondary authentication from the VPN user. • Fallback when a certificate is unavailable —This attribute is configurable only if “Hide username from end user” is checked. Uses Cisco Secure Desktop Host Scan data to pre-fill the username for secondary authentication if a certificate is unavailable. • Password—Choose one of the following methods to retrieve the password to be used for secondary authentication: – Prompt—Prompt the user for the password. – Use Primary—Reuse the primary authentication password for all secondary authentications. – Use—Enter a common secondary password for all secondary authentications. • Specify the certificate fields to be used as the username—Specifies one or more fields to match as the username. To use this username in the pre-fill username from certificate feature for the secondary username/password authentication or authorization, you must also configure the pre-fill-username and secondary-pre-fill-username. – Primary Field—Selects the first field to use from the certificate for the username. If this value is found, the secondary field is ignored. – Secondary Field—Selects the field to us if the primary field is not found. The options for primary and secondary field attributes include the following: Cisco ASA Series VPN ASDM Configuration Guide 4-65 Chapter 4 General VPN Setup Configuring AnyConnect VPN Connections Attribute Definition C Country: the two-letter country abbreviation. These codes conform to ISO 3166 country abbreviations. CN Common Name: the name of a person, system, or other entity. Not available a s a secondary attribute. DNQ Domain Name Qualifier. EA E-mail address. GENQ Generational Qualifier. GN Given Name. I Initials. L Locality: the city or town where the organization is located. N Name. O Organization: the name of the company, institution, agency, association or other entity. OU Organizational Unit: the subgroup within the organization (O). SER Serial Number. SN Surname. SP State/Province: the state or province where the organization is located T Title. UID User Identifier. UPN User Principal Name. • Use the entire DN as the username—Uses the entire subject DN (RFC1779) to derive a name for an authorization query from a digital certificate. • Use script to select username—Names the script from which to extract a username from a digital certificate. The default is --None--. – Add or Edit—Opens the Add or Edit Script Content dialog box, in which you can define a script to use in mapping the username from the certificate. – Delete—Deletes the selected script. There is no confirmation or undo. Configuring Authorization Attributes for an SSL VPN Connection Profile The Authorization dialog box lets you view, add, edit, or delete interface-specific authorization server groups. Each row of the table on this dialog box shows the status of one interface-specific server group: the interface name, its associated server group, and whether fallback to the local database is enabled if the selected server group fails. Fields • Authorization Server Group—Specifies an authorization server group from which to draw authorization parameters. – Server Group—Selects an authorization server group to use. The default is none. Cisco ASA Series VPN ASDM Configuration Guide 4-66 Chapter 4 General VPN Setup Configuring AnyConnect VPN Connections – Manage—Opens the Configure AAA Server Groups dialog box. – Users must exist in the authorization database to connect—Select this check box to require that users meet this criterion. • Interface-specific Authorization Server Groups—Manages the assignment of authorization server groups to specific interfaces. – Add or Edit—Opens the Assign Authentication Server Group to Interface dialog box, in which you can specify the interface and server group, and specify whether to allow fallback to the LOCAL database if the selected server group fails. The Manage button on this dialog box opens the Configure AAA Server Groups dialog box. Your selections appear in the Interface/Server Group table. – Delete—Removes the selected server group from the table. There is no confirmation or undo. • Username Mapping from Certificate—Specify the fields in a digital certificate from which to extract the username. – Use script to select username—Specifies the name of a script to use to select a username from a digital certificate. The default is --None--. – Add or Edit—Opens the Add or Edit Script Content dialog box, in which you can define a script to use in mapping the username from the certificate. – Delete—Deletes the selected script. There is no confirmation or undo. – Use the entire DN as the username—Specifies that you want to use the entire Distinguished Name field of the certificate as the username. – Specify the certificate fields to be used as the username—Specifies one or more fields to combine into the username. – Primary Field—Selects the first field to use in the certificate for the username. If this value is found, the secondary field is ignored. – Secondary Field—Selects the field to use if the primary field is not found. • Find—Enter a GUI label or a CLI command to use as a search string, then click Next or Previous to begin the search. Adding or Editing Content to a Script for Certificate Pre-Fill-Username The Add or Edit Script Content dialog box lets you create an authentication or authorization script. Note Both AnyConnect client and clientless WebVPN display “Unknown” in the username field when pre-fill-username from certificate using a script cannot find the username in the client certificate. Fields • Script Name—Specify the name of the script. The script name must be the same in both authorization and authentication.You define the script here, and CLI uses the same script to perform this function. • Select script parameters—Specify the attributes and content of the script. • Value for Username—Select an attribute from the drop-down list of standard DN attributes to use as the username (Subject DN). • No Filtering—Specify that you want to use the entire specified DN name. Cisco ASA Series VPN ASDM Configuration Guide 4-67 Chapter 4 General VPN Setup Configuring AnyConnect VPN Connections • Filter by substring— Specify the Starting Index (the position in the string of the first character to match) and Ending Index (number of characters to search). If you choose this option, the starting index cannot be blank. If you leave the ending index blank, it defaults to -1, indicating that the entire string is searched for a match. For example, suppose you selected the DN attribute Common Name (CN), which contains a value of host/user. Table 4-3 shows some possible ways you might filter this value using the substring option to achieve various return values. The Return Value is what is actually pre-filled as the username. Table 4-3 Filtering by Substring Starting Index Ending Index Return Value 1 5 host/ 6 10 user 6 -1 user Using a negative index, as in the third row of this table, specifies to count from the end of the string backwards to the end of the substring, in this case, the “r” of “user”. When using filtering by substrings, you should know the length of the substring that you are seeking. From the following examples, use either the regular expression matching or the custom script in Lua format: • Example 1: Regular Expression Matching—Enter a regular expression to apply to the search in the Regular Expression field. Standard regular expression operators apply. For example, suppose you want to use a regular expression to filter everything up to the @ symbol of the “Email Address (EA)” DN value. The regular expression ^[^@]* would be one way to do this. In this example, if the DN value contained a value of user1234@example.com, the return value after the regular expression would be user1234. • Example 2: Use custom script in Lua format—Specify a custom script written in the Lua programming language to parse the search fields. Selecting this option makes available a field in which you can enter your custom Lua script; for example, the script: return cert.subject.cn..'/'..cert.subject.l combines two DN fields, username (cn) and locality (l), to use as a single username and inserts the slash (/) character between the two fields. Table 4-4 lists the attribute names and descriptions that you can use in a Lua script. Note Lua is case-sensitive. Table 4-4 Attribute Names and Descriptions Attribute Name Description cert.subject.c Country cert.subject.cn Common Name cert.subject.dnq DN qualifier cert.subject.ea E-mail Address cert.subject.genq Generational qualified Cisco ASA Series VPN ASDM Configuration Guide 4-68 Chapter 4 General VPN Setup Configuring AnyConnect Secure Mobility Table 4-4 Attribute Names and Descriptions cert.subject.gn Given Name cert.subject.i Initials cert.subject.l Locality cert.subject.n Name cert.subject.o Organization cert.subject.ou Organization Unit cert.subject.ser Subject Serial Number cert.subject.sn Surname cert.subject.sp State/Province cert.subject.t Title cert.subject.uid User ID cert.issuer.c Country cert.issuer.cn Common Name cert.issuer.dnq DN qualifier cert.issuer.ea E-mail Address cert.issuer.genq Generational qualified cert.issuer.gn Given Name cert.issuer.i Initials cert.issuer.l Locality cert.issuer.n Name cert.issuer.o Organization cert.issuer.ou Organization Unit cert.issuer.ser Issuer Serial Number cert.issuer.sn Surname cert.issuer.sp State/Province cert.issuer.t Title cert.issuer.uid User ID cert.serialnumber Certificate Serial Number cert.subjectaltname.upn User Principal Name If an error occurs while activating a tunnel group script, causing the script not to activate, the administrator’s console displays an error message. Configuring AnyConnect Secure Mobility AnyConnect Secure Mobility protects corporate interests and assets from Internet threats when employees are mobile. Use the Mobile User Security dialog box to configure this feature. AnyConnect Secure Mobility lets Cisco IronPort S-Series Web Security appliances scan Cisco AnyConnect secure Cisco ASA Series VPN ASDM Configuration Guide 4-69 Chapter 4 General VPN Setup Configuring AnyConnect Secure Mobility mobility clients to ensure that clients are protected from malicious software and/or inappropriate sites. The client periodically checks to ensure that Cisco IronPort S-Series Web Security appliance protection is enabled. To configure secure mobility solutions, choose Configuration > Remote Access VPN > Network (Client) Access > Mobile User Security. This feature requires a release of the Cisco IronPort Web Security appliance that provides AnyConnect Secure Mobility licensing support for the Cisco AnyConnect secure mobility client. It also requires an AnyConnect release that supports the AnyConnect Secure Mobility feature. Note Figure 4-6 Mobile User Security Window Fields • Service Access Control—Specifies from which host or network address the WSAs can communicate. – Add—Opens the Add MUS Access Control Configuration dialog box for the selected connection. – Edit—Opens the Edit MUS Access Control Configuration dialog box for the selected connection. – Delete—Removes the selected connection from the table. There is no confirmation or undo. • Enable Mobile User Security Service—Starts the connection with the client through the VPN. If enabled, you are required to enter a password, used by the WSA when contacting the ASA. If no WSA is present, the status is disabled. • Service Port—If you choose to enable the service, specify which port number for the service to use. The port must be between 1 and 65535 and must match the corresponding value provisioned into the WSA with the management system. The default is 11999. • Change Password—Enables you to change the WSA access password. Cisco ASA Series VPN ASDM Configuration Guide 4-70 Chapter 4 General VPN Setup Configuring Clientless SSL VPN Connections • WSA Access Password—Specify the shared secret password required for authentication between the ASA and WSA. This password must match the corresponding password provisioned into the WSA with the management system. • Confirm Password—Re-enter the specified password. • Show WSA Sessions—Allows you to view session information of WSAs connected to the ASA.The host IP address of the WSA that is connected (or has been connected) and the duration of the connection is returned in a dialog box. Add or Edit MUS Access Control The Add or Edit MUS Access Control dialog box lets you configure MUS access. Fields • Interface Name—Use the drop-down menu to choose which interface name you are adding or editing. • IP Address—Enter either an IPv4 or IPv6 address. • Mask—Use the drop-down menu to choose the appropriate mask. Configuring Clientless SSL VPN Connections Use the Clientless SSL VPN Access Connections dialog box to configure clientless SSL VPN access parameters. This dialog box also records the configuration choices you make in its child dialog boxes. Fields • Access Interfaces—Lets you select from a table the interfaces on which to enable access. The fields in this table include the interface name and check boxes specifying whether to allow access. – Device Certificate—Lets you specify a certificate for authentication for either an RSA key or an ECDSA key or trustpoint. You have the option to configure two trustpoints. The client indicates ECDSA support with a vendor ID payload. The ASA scans the configured trustpoint list and chooses the first one that the client supports. If ECDSA is preferred, you should configure that trustpoint before the RSA trustpoint. – Manage—Opens the Manage Identity Certificates dialog box, on which you can add, edit, delete, export, and show details for a selected certificate. – Port Setting—Configure port numbers for clientless SSL and IPsec (IKEv2) connections. The range is 1-65535. The default is port 443. • Login Page Setting – Allow user to select connection profile, identified by its alias, on the login page. Otherwise, DefaultWebVPN Group will be the connection profile.—Specifies that the user login page presents the user with a drop-down menu from which the user can select a particular tunnel group with which to connect. – Allow user to enter internal password on the login page.—Adds an option to input a different password when accessing internal servers. – Shutdown portal login page.—Shows the web page when the login is disabled. Cisco ASA Series VPN ASDM Configuration Guide 4-71 Chapter 4 General VPN Setup Configuring Clientless SSL VPN Connections • Connection Profiles—Provides a connection table that shows the records that determine the connection policy for this connection (tunnel group). Each record identifies a default group policy for the connection and contains protocol-specific connection parameters. – Add—Opens the Add Clientless SSL VPN dialog box for the selected connection. – Edit—Opens the Edit Clientless SSL VPN dialog box for the selected connection. – Delete—Removes the selected connection from the table. There is no confirmation or undo. – Name—The name of the Connection Profile. – Enabled—Checkmark when enabled. – Aliases—Other names by which the Connection Profile is known. – Authentication Method—Specifies which authentication method is used. – Group Policy—Shows the default group policy for this Connection Profile. • Let group URL take precedence if group URL and certificate map match different connection profiles. Otherwise, the connection profile matches the certificate map will be used.—This option specifies the relative preference of the group URL and certificate values during the connection profile selection process. If the ASA fails to match the preferred value specified by the endpoint to that specified by a connection profile, it chooses the connection profile that matches the other value. Check this option only if you want to rely on the preference used by many older ASA software releases to match the group URL specified by the VPN endpoint to the connection profile that specifies the same group URL. This option is unchecked by default. If it is unchecked, the ASA prefers to match the certificate field value specified in the connection profile to the field value of the certificate used by the endpoint to assign the connection profile. Add or Edit Clientless SSL VPN Connections The Add or Edit SSL VPN dialog box consists of Basic and Advanced sections, accessible through the expandable menu on the left of the box. Add or Edit Clientless SSL VPN Connections > Basic The Basic dialog box lets you configure essential characteristics for this connection. Fields • Name—Specifies the name of the connection. For the edit function, this field is read-only. • Aliases—(Optional) Specifies one or more alternate names for this connection. The aliases appear on the login page if you configure that option on the Clientless SSL VPN Access Connections dialog box. • Authentication—Specifies the authentication parameters. – Method—Specifies whether to use AAA authentication, certificate authentication, or both methods for this connection. The default is AAA authentication. – AAA server Group—Selects the AAA server group to use for authenticating this connection. The default is LOCAL. – Manage—Opens the Configure AAA Server Groups dialog box. • DNS Server Group—Selects the server to use as the DNS server group for this connection. The default is DefaultDNS. Cisco ASA Series VPN ASDM Configuration Guide 4-72 Chapter 4 General VPN Setup Configuring Clientless SSL VPN Connections • Default Group Policy—Specifies the default group policy parameters to use for this connection. – Group Policy—Selects the default group policy to use for this connection. The default is DfltGrpPolicy. – Clientless SSL VPN Protocol—Enables or disables the Clientless SSL VPN protocol for this connection. Add or Edit Clientless SSL VPN Connections > Advanced The Advanced menu items and their dialog boxes let you configure the following characteristics for this connection: • General attributes. • Authentication attributes. • Authorization attributes. • Accounting attributes. • Name server attributes. • Clientless SSL VPN attributes. Add or Edit Clientless SSL VPN Connections > Advanced > General Use this dialog box to specify whether to strip the realm and group from the username before passing them to the AAA server, and to specify password management options. Fields • Password Management—Lets you configure parameters relevant to overriding an account-disabled indication from a AAA server and to notifying users about password expiration. – Enable notification password management—Checking this check box makes the following two parameters available. You can select either to notify the user at login a specific number of days before the password expires or to notify the user only on the day that the password expires. The default is to notify the user 14 days prior to password expiration and every day thereafter until the user changes the password. The range is 1 through 180 days. Note This does not change the number of days before the password expires, but rather, it enables the notification. If you select this option, you must also specify the number of days. In either case, and, if the password expires without being changed, the ASA offers the user the opportunity to change the password. If the current password has not yet expired, the user can still log in using that password. This parameter is valid for AAA servers that support such notification; that is, RADIUS, RADIUS with an NT server, and LDAP servers. The ASA ignores this command if RADIUS or LDAP authentication has not been configured. – Override account-disabled indication from AAA server—Overrides an account-disabled indication from a AAA server. Cisco ASA Series VPN ASDM Configuration Guide 4-73 Chapter 4 General VPN Setup Configuring Clientless SSL VPN Connections Allowing override account-disabled is a potential security risk. Note Add or Edit Clientless or SSL VPN Client Connection Profile or IPsec Connection Profiles> Advanced > Authentication The Authentication dialog box lets you view, add, edit, or delete interface-specific authentication server groups. Each row of the table on this dialog box shows the status of one interface-specific server group: the interface name, its associated server group, and whether fallback to the local database is enabled if the selected server group fails. Fields • Interface-specific Authorization Server Groups—Manages the assignment of authorization server groups to specific interfaces. – Add or Edit—Opens the Assign Authentication Server Group to Interface dialog box, in which you can specify the interface and server group, and specify whether to allow fallback to the LOCAL database if the selected server group fails. The Manage button on this dialog box opens the Configure AAA Server Groups dialog box. Your selections appear in the Interface/Server Group table. – Delete—Removes the selected server group from the table. There is no confirmation or undo. Assign Authentication Server Group to Interface This dialog box lets you associate an interface with a AAA server group. The results appear in the table on the Authentication dialog box. Fields • Interface—Selects an interface, DMZ, Outside, or Inside. The default is DMZ. • Server Group—Selects a server group to assign to the selected interface. The default is LOCAL. • Manage—Opens the Configure AAA Server Groups dialog box. • Fallback—Enables or disables fallback to LOCAL if the selected server group fails. Add or Edit SSL VPN Connections > Advanced > Authorization This dialog box lets you configure the default authorization server group, interface-specific authorization server groups, and user name mapping attributes. The attributes are the same for SSL VPN and Clientless SSL VPN connections. Fields • Default Authorization Server Group—Configures default authorization server group attributes. – Server Group—Selects the authorization server group to use for this connection. The default is --None--. – Manage—Opens the Configure AAA Server Groups dialog box. – Users must exist in the authorization database to connect—Enables or disables this requirement. Cisco ASA Series VPN ASDM Configuration Guide 4-74 Chapter 4 General VPN Setup Configuring Clientless SSL VPN Connections • Interface-specific Authorization Server Groups – Table—Lists each configured interface and the server group with which it is associated. – Add or Edit—Opens the Assign Authorization Server Group to Interface dialog box. – Delete—Removes the selected row from the table. • User Name Mapping—Specifies user name mapping attributes. • Username Mapping from Certificate—Lets you specify the fields in a digital certificate from which to extract the username. – Pre-fill Username from Certificate —Enables the use of a username extracted from the specified certificate field as the username for username/password authentication and authorization, using the options that follow in this dialog box. – Hide username from end user—Specifies not to display the extracted username to the end user. – Use script to select username—Specify the name of a script to use to select a username from a digital certificate. There is no default. – Add or Edit—Opens the Add or Edit Script Content dialog box, in which you can define a script to use in mapping the username from the certificate. – Delete—Deletes the selected script. There is no confirmation or undo. – Use the entire DN as the username—Enables or disables the requirement to use the entire DN as the username. – Specify individual DN fields as the username. You can select both the primary DN field, for which the default is CN (Common Name) and the secondary DN field, for which the default is OU (Organization Unit). – Primary Field—Selects the first field to use in the username. – Secondary Field—Selects the second field to use in the username. Assign Authorization Server Group to Interface This dialog box lets you associate an interface with a AAA server group. The results appear in the table on the Authorization dialog box. Fields • Interface—Selects an interface, DMZ, Outside, or Inside. The default is DMZ. • Server Group—Selects a server group to assign to the selected interface. The default is LOCAL. • Manage—Opens the Configure AAA Server Groups dialog box. Add or Edit SSL VPN Connections > Advanced > SSL VPN This dialog box lets you configure attributes that affect what the remote user sees upon login. Fields • Portal Page Customization—Configures the look and feel of the user login page by specifying which preconfigured customization attributes to apply. The default is DfltCustomization. • Enable the display of Radius Reject-Message on the login screen—Select this check box to display the RADIUS-reject message on the login dialog box when authentication is rejected. Cisco ASA Series VPN ASDM Configuration Guide 4-75 Chapter 4 General VPN Setup Configuring Clientless SSL VPN Connections • Enable the display of SecurId message on the login screen—Select this check box to display SecurID messages on the login dialog box. • Manage—Opens the Configure GUI Customization Objects dialog box. • Connection Aliases—Lists in a table the existing connection aliases and their status and lets you add or delete items in that table. A connection alias appears on the user login page if the connection is configured to allow users to select a particular connection (tunnel group) at login. The rows in this table are editable in place, so there is no Edit button. Clicking the “i” icon above the table opens a tooltip for the edit function. – Add—Opens the Add Connection Alias dialog box, on which you can add and enable a connection alias. – Delete—Removes the selected row from the connection alias table. There is no confirmation or undo. – To edit an alias listed in the table, double-click the line. • Group URLs—Lists in a table the existing group URLs and their status and lets you add or delete items in that table. A group URL appears on the user login page if the connection is configured to allow users to select a particular group at login. The rows in this table are editable in place, so there is no Edit button. Clicking the “i” icon above the table opens a tooltip for the edit function. – Add—Opens the Add Group URL dialog box, on which you can add and enable a group URL. – Delete—Removes the selected row from the connection alias table. There is no confirmation or undo. – To edit a URL listed in the table, double-click the line. • Do not run Cisco Secure Desktop (CSD) on client machine when using group URLs defined above to access the ASA. (If a client connects using a connection alias, this setting is ignored.)—Check if you want to exempt users from running CSD who use a URL that matches an entry in the Group URLs table. Be aware that doing so stops the security appliance from receiving endpoint criteria from these users, so you might have to change the DAP configuration to provide them with VPN access. Add or Edit Clientless SSL VPN Connections > Advanced > Clientless SSL VPN This dialog box lets you configure attributes that affect what the remote user sees upon login. Fields • Portal Page Customization—Configures the look and feel of the user login page by specifying which preconfigured customization attributes to apply. The default is DfltCustomization. • Enable the display of Radius Reject-Message on the login screen—Select this check box to display the RADIUS-reject message on the login dialog box when authentication is rejected. • Enable the display of SecurId message on the login screen—Select this check box to display SecurID messages on the login dialog box. • Manage—Opens the Configure GUI Customization Objects dialog box. • Connection Aliases—Lists in a table the existing connection aliases and their status and lets you add or delete items in that table. A connection alias appears on the user login page if the connection is configured to allow users to select a particular connection (tunnel group) at login. – Add—Opens the Add Connection Alias dialog box, on which you can add and enable a connection alias. Cisco ASA Series VPN ASDM Configuration Guide 4-76 Chapter 4 General VPN Setup Configuring Clientless SSL VPN Connections – Delete—Removes the selected row from the connection alias table. There is no confirmation or undo. • Group URLs—Lists in a table the existing group URLs and their status and lets you add or delete items in that table. A group URL appears on the user login page if the connection is configured to allow users to select a particular group at login. – Add—Opens the Add Group URL dialog box, on which you can add and enable a group URL. – Delete—Removes the selected row from the connection alias table. There is no confirmation or undo. • Do not run Cisco Secure Desktop (CSD) on client machine when using group URLs defined above to access the ASA. (If a client connects using a connection alias, this setting is ignored.)—Check if you want to exempt users from running CSD who use a URL that matches an entry in the Group URLs table. Be aware that doing so stops the security appliance from receiving endpoint criteria from these users, so you might have to change the DAP configuration to provide them with VPN access. Add or Edit Clientless SSL VPN Connections > Advanced > NetBIOS Servers The table on this dialog box shows the attributes of the already-configured NetBIOS servers. The Add or Edit Tunnel Group dialog box for Clientless SSL VPN access, NetBIOS dialog box, lets you configure the NetBIOS attributes for the tunnel group. Clientless SSL VPN uses NetBIOS and the Common Internet File System protocol to access or share files on remote systems. When you attempt a file-sharing connection to a Windows computer by using its computer name, the file server you specify corresponds to a specific NetBIOS name that identifies a resource on the network. The ASA queries NetBIOS name servers to map NetBIOS names to IP addresses. Clientless SSL VPN requires NetBIOS to access or share files on remote systems. To make the NBNS function operational, you must configure at least one NetBIOS server (host). You can configure up to 3 NBNS servers for redundancy. The ASA uses the first server on the list for NetBIOS/CIFS name resolution. If the query fails, it uses the next server. Fields • IP Address—Displays the IP addresses of configured NetBIOS servers. • Master Browser—Shows whether a server is a WINS server or one that can also be a CIFS server (that is, a master browser). • Timeout (seconds)—Displays the initial time in seconds that the server waits for a response to an NBNS query before sending the query to the next server. • Retries—Shows the number of times to retry sending an NBNS query to the configured servers, in order. In other words, this is the number of times to cycle through the list of servers before returning an error. The minimum number of retries is 0. The default number of retries is 2. The maximum number of retries is 10. • Add/Edit—Click to add a NetBIOS server. This opens the Add or Edit NetBIOS Server dialog box. • Delete—Removes the highlighted NetBIOS row from the list. • Move Up/Move Down—The ASA sends NBNS queries to the NetBIOS servers in the order in which they appear in this box. Use this box to change the priority order of the servers by moving them up or down in the list. Cisco ASA Series VPN ASDM Configuration Guide 4-77 Chapter 4 General VPN Setup IPsec Remote Access Connection Profiles Configure DNS Server Groups This dialog box displays the configured DNS servers in a table, including the server group name, servers, timeout in seconds, number of retries allowed, and domain name. You can add, edit, or delete DNS server groups on this dialog box. Fields • Add or Edit—Opens the Add or Edit DNS Server Group dialog box. • Delete—Removes the selected row from the table. There is no confirmation or undo. • DNS Server Group—Selects the server to use as the DNS server group for this connection. The default is DefaultDNS. • Manage—Opens the Configure DNS Server Groups dialog box. Add or Edit Clientless SSL VPN Connections > Advanced > Clientless SSL VPN This dialog box lets you specify portal-related attributes for Clientless SSL VPN connections. Fields • Portal Page Customization—Selects the customization to apply to the user interface. • Manage—Opens the Configure GUI Customization Objects dialog box. IPsec Remote Access Connection Profiles Configuration > VPN > General > Tunnel Group The parameters in the IPsec Connection Profiles dialog box let you configure IPsec remote access connections. Most of the parameters in this section were formerly configured under tunnel groups. An IPsec connection represents a connection-specific record for IPsec and Clientless SSL VPN connections. The IPsec group uses the IPsec connection parameters to create a tunnel. An IPsec connection can be either remote-access or Site-to-Site. The IPsec group is configured on the internal server or on an external RADIUS server. For ASA 5505 in client mode or VPN 3002 hardware client parameters, which enable or disable interactive hardware client authentication and individual user authentication, the IPsec connection parameters take precedence over parameters set for users and groups. The Clientless SSL VPN tunnel-group parameters are the parameters of the Clientless SSL VPN group that you want to apply to this IPsec connection. You configure Clientless SSL VPN access on the Configuration > Clientless SSL VPN dialog box. Fields • Access Interfaces—Selects the interfaces to enable for IPsec access. The default is that no access is selected. • Connections—Shows in tabular format the configured parameters for existing IPsec connections. The Connections table contains records that determine connection policies. A record identifies a default group policy for the connection and contains protocol-specific connection parameters. The table contains the following columns: – Name—Specifies the name or IP address of the IPsec connection. – ID Certificate—Specifies the name of the ID certificate, if available. Cisco ASA Series VPN ASDM Configuration Guide 4-78 Chapter 4 General VPN Setup Add or Edit an IPsec Remote Access Connection Profile – IPsec Protocol—Indicates whether the IPsec protocol is enabled. You enable this protocol on the Add or Edit IPsec Remote Access Connection, Basic dialog box. – L2TP/IPsec Protocol—Indicates whether the L2TP/IPsec protocol is enabled. You enable this protocol on the Add or Edit IPsec Remote Access Connection, Basic dialog box. – Group Policy—Indicates the name of the group policy for this IPsec connection. • Add or Edit—Opens the Add or Edit IPsec Remote Access Connection Profile dialog box. • Delete—Removes the selected server group from the table. There is no confirmation or undo. Add or Edit an IPsec Remote Access Connection Profile The Add or Edit IPsec Remote Access Connection Profile dialog box has a navigation pane that lets you select basic or advanced elements to configure. Add or Edit IPsec Remote Access Connection Profile Basic The Add or Edit IPsec Remote Access Connection Profile Basic dialog box lets you configure common attributes for IPsec connections. Fields • Name—Identifies the name of the connection. • IKE Peer Authentication—Configures IKE peers. – Pre-shared key—Specifies the value of the pre-shared key for the connection. The maximum length of a pre-shared key is 128 characters. – Identity Certificate—Selects the name of an identity certificate, if any identity certificates are configured and enrolled. – Manage—Opens the Manage Identity Certificates dialog box, on which you can add, edit, delete, export, and show details for a selected certificate. • User Authentication—Specifies information about the servers used for user authentication. You can configure more authentication information in the Advanced section. – Server Group—Selects the server group to use for user authentication. the default is LOCAL. If you select something other than LOCAL, the Fallback check box becomes available. – Manage—Opens the Configure AAA Server Groups dialog box. – Fallback—Specifies whether to use LOCAL for user authentication if the specified server group fails. • Client Address Assignment—Specifies attributes relevant to assigning client attributes. – DHCP Servers—Specifies the IP address of a DHCP server to use. You can add up to 10 servers, separated by spaces. – Client Address Pools—Specifies up to 6 predefined address pools. To define an address pool, go to Configuration > Remote Access VPN > Network Client Access > Address Assignment > Address Pools. – Select—Opens the Select Address Pools dialog box. • Default Group Policy—Specifies attributes relevant to the default group policy. Cisco ASA Series VPN ASDM Configuration Guide 4-79 Chapter 4 General VPN Setup Mapping Certificates to IPsec or SSL VPN Connection Profiles – Group Policy—Selects the default group policy to use for this connection. The default is DfltGrpPolicy. – Manage—Opens the Configure Group Policies dialog box, from which you can add, edit, or delete group policies. – Client Protocols—Selects the protocol or protocols to use for this connection. By default, both IPsec and L2TP over IPsec are selected. Mapping Certificates to IPsec or SSL VPN Connection Profiles When the ASA receives an IPsec connection request with client certificate authentication, it assigns a connection profile to the connection according to policies you configure. That policy can be to use rules you configure, use the certificate OU field, use the IKE identity (i.e. hostname, IP address, key ID), the peer IP address, or a default connection profile. For SSL connections, the ASA only uses the rules you configure. For IPsec or SSL connections using rules, the ASA evaluates the attributes of the certificate against the rules until it finds a match. When it finds a match, it assigns the connection profile associated with the matched rule to the connection. If it fails to find a match, it assigns the default connection profile (DefaultRAGroup for IPsec and DefaultWEBVPNGroup for SSL VPN) to the connection and lets the user choose the connection profile from a drop-down menu displayed on the portal page (if it is enabled). The outcome of the connection attempt once in this connection profile depends on whether or not the certificate is valid and the authentication settings of the connection profile. A certificate group matching policy defines the method to use for identifying the permission groups of certificate users. You can use any or all of these methods. First configure the policy for matching a certificate to a connection profile at Configuration > Remote Access VPN > Network (Client) Access > Advanced > IPsec > Certificate to Connection Profile Maps. If you choose to use rules you configure, go to Rules to specify the rules. The following procedures shows how you create the certificate-based criteria for each IPsec and SSL VPN connection profile: Step 1 Use the table at the top (Certificate to Connection Profile Maps) to do one of the following: • Create a list name, called a “map,” specify the priority of the list, and assign the list to a connection profile. ASDM highlights the list after you add it to the table. • Confirm that a list is assigned to the connection profile for which you want to add certificate-based rules. ASDM highlights the list after you add it to the table and displays any associated list entries in the table at the bottom of the pane. Step 2 Use the table at the bottom (Mapping Criteria) to view, add, change or delete entries to the selected list. Each entry in the list consists of one certificate-based rule. All of the rules in the mapping criteria list need to match the contents of the certificate for the ASA to choose the associated map index. To assign a connection if one criterion or another matches, create one list for each matching criterion. To understand the fields, see the following sections: • Setting a Certificate Matching Policy • Add/Edit Certificate Matching Rule Cisco ASA Series VPN ASDM Configuration Guide 4-80 Chapter 4 General VPN Setup Mapping Certificates to IPsec or SSL VPN Connection Profiles • Add/Edit Certificate Matching Rule Criterion Setting a Certificate Matching Policy For IPsec connections, a certificate group matching policy defines the method to use for identifying the permission groups of certificate users. You can use any or all of these methods: Fields • Use the configured rules to match a certificate to a group—Lets you use the rules you have defined under Rules. • Use the certificate OU field to determine the group—Lets you use the organizational unit field to determine the group to which to match the certificate. This is selected by default. • Use the IKE identity to determine the group—Lets you use the identity you previously defined under Configuration > VPN > IKE > Global Parameters. The IKE identity can be hostname, IP address, key ID, or automatic. • Use the peer IP address to determine the group—Lets you use the peer's IP address. This is selected by default. • Default to group—Lets you select a default group for certificate users that is used when none of the preceding methods resulted in a match. This is selected by default. Click the default group in the Default to group list. The group must already exist in the configuration. If the group does not appear in the list, you must define it by using Configuration > VPN > General > Tunnel Group. Add/Edit Certificate Matching Rule Configuration > VPN > IKE > Certificate Group Matching > Rules > Add/Edit Certificate Matching Rule Use the Add/Edit Certificate Matching Rule dialog box to assign the name of a list (map) to a connection profile. Fields • Map—Choose one of the following: – Existing—Select the name of the map to include the rule. – New—Enter a new map name for a rule. • Rule Priority—Type a decimal to specify the sequence with which the ASA evaluates the map when it receives a connection request. For the first rule defined, the default priority is 10. The ASA evaluates each connection against the map with the lowest priority number first. • Mapped to Connection Profile—Select the connection profile, formerly called a “tunnel group,” to map to this rule. Cisco ASA Series VPN ASDM Configuration Guide 4-81 Chapter 4 General VPN Setup Mapping Certificates to IPsec or SSL VPN Connection Profiles If you do not assign a rule criterion to the map, as described in the next section, the ASA ignores the map entry. Add/Edit Certificate Matching Rule Criterion Configuration > VPN > IKE > Certificate Group Matching > Rules > Add/Edit Certificate Matching Rule Criterion Use the Add/Edit Certificate Matching Rule Criterion dialog box to configure a certificate matching rule criterion for the selected connection profile. Fields • Rule Priority—(Display only). Sequence with which the ASA evaluates the map when it receives a connection request. The ASA evaluates each connection against the map with the lowest priority number first. • Mapped to Group—(Display only). Connection profile to which the rule is assigned. • Field—Select the part of the certificate to be evaluated from the drop-down list. – Subject—The person or system that uses the certificate. For a CA root certificate, the Subject and Issuer are the same. – Alternative Subject—The subject alternative names extension allows additional identities to be bound to the subject of the certificate. – Issuer—The CA or other entity (jurisdiction) that issued the certificate. – Extended Key Usage—An extension of the client certificate that provides further criteria that you can choose to match. Cisco ASA Series VPN ASDM Configuration Guide 4-82 Chapter 4 General VPN Setup Mapping Certificates to IPsec or SSL VPN Connection Profiles • Component—(Applies only if Subject of Issuer is selected.) Select the distinguished name component used in the rule: DN Field Definition Whole Field The entire DN. Country (C) The two-letter country abbreviation. These codes conform to ISO 3166 country abbreviations. Common Name (CN) The name of a person, system, or other entity. This is the lowest (most specific) level in the identification hierarchy. DN Qualifier (DNQ) A specific DN attribute. E-mail Address (EA) The e-mail address of the person, system or entity that owns the certificate. Generational Qualifier A generational qualifier such as Jr., Sr., or III. (GENQ) Given Name (GN) The first name of the certificate owner. Initials (I) The first letters of each part of the certificate owner’s name. Locality (L) The city or town where the organization is located. Name (N) The name of the certificate owner. Organization (O) The name of the company, institution, agency, association, or other entity. Organizational Unit (OU) The subgroup within the organization. Serial Number (SER) The serial number of the certificate. Surname (SN) The family name or last name of the certificate owner. State/Province (S/P) The state or province where the organization is located. Title (T) The title of the certificate owner, such as Dr. User ID (UID) The identification number of the certificate owner. Unstructured Name (UNAME) The unstructuredName attribute type specifies the name or names of a subject as an unstructured ASCII string. IP Address (IP) IP address field. • Operator—Select the operator used in the rule: – Equals—The distinguished name field must exactly match the value. – Contains—The distinguished name field must include the value within it. – Does Not Equal—The distinguished name field must not match the value – Does Not Contain—The distinguished name field must not include the value within it. • Value—Enter up to 255 characters to specify the object of the operator. For Extended Key Usage, select one of the pre-defined values in the drop-down list, or you can enter OIDs for other extensions. The pre-defined values include the following: Cisco ASA Series VPN ASDM Configuration Guide 4-83 Chapter 4 General VPN Setup Mapping Certificates to IPsec or SSL VPN Connection Profiles Selection Key Usage Purpose OID String clientauth Client Authentication 1.3.6.1.5.5.7.3.2 codesigning Code Signing 1.3.6.1.5.5.7.3.3 emailprotection Secure Email Protection 1.3.6.1.5.5.7.3.4 ocspsigning OCSP Signing 1.3.6.1.5.5.7.3.9 serverauth Server Authentication 1.3.6.1.5.5.7.3.1 timestamping Time Stamping 1.3.6.1.5.5.7.3.8 Site-to-Site Connection Profiles The Connection Profiles dialog box shows the attributes of the currently configured Site-to-Site connection profiles (tunnel groups), lets you select the delimiter to use when parsing connection profile names, and lets you add, modify, or delete connection profiles. The security appliance supports IPsec LAN-to-LAN VPN connections for IPv4 or IPv6 using IKEv1 or IKEv2 and supports both inside and outside networks using the inner and outer IP headers. Fields • Access Interfaces—Displays a table of device interfaces where you can enable access by a remote peer device on the interface: – Interface—The device interface to enable or disable access. – Allow IKEv1 Access—Check to enable IPsec IKEv1 access by a peer device. – Allow IKEv2 Access—Check to enable IPsec IKEv2 access by a peer device. • Connection Profiles—Displays a table of connection profiles where you can add, edit, or delete profiles: – Add—Opens the Add IPsec Site-to-Site connection profile dialog box. – Edit—Opens the Edit IPsec Site-to-Site connection profile dialog box. – Delete—Removes the selected connection profile. There is no confirmation or undo. – Name—The name of the connection profile. – Interface—The interface the connection profile is enabled on. – Local Network—Specifies the IP address of the local network. – Remote Network—Specifies the IP address of the remote network. – IKEv1 Enabled—Shows IKEv1 enabled for the connection profile. – IKEv2 Enabled—Shows IKEv2 enabled for the connection profile. – Group Policy—Shows the default group policy of the connection profile. Cisco ASA Series VPN ASDM Configuration Guide 4-84 Chapter 4 General VPN Setup Mapping Certificates to IPsec or SSL VPN Connection Profiles Add/Edit Site-to-Site Connection You can get to this panel through various paths. The Add or Edit IPsec Site-to-Site Connection dialog box lets you create or modify an IPsec Site-to-Site connection. These dialog boxes let you specify the peer IP address (IPv4 or IPv6), specify a connection name, select an interface, specify IKEv1 and IKEv2 peer and user authentication parameters, specify protected networks, and specify encryption algorithms. The ASA supports LAN-to-LAN VPN connections to Cisco or third-party peers when the two peers have IPv4 inside and outside networks (IPv4 addresses on the inside and outside interfaces). For LAN-to-LAN connections using mixed IPv4 and IPv6 addressing, or all IPv6 addressing, the security appliance supports VPN tunnels if both peers are Cisco ASA 5500 series security appliances, and if both inside networks have matching addressing schemes (both IPv4 or both IPv6). Specifically, the following topologies are supported when both peers are Cisco ASA 5500 series ASAs: • The ASAs have IPv4 inside networks and the outside network is IPv6 (IPv4 addresses on the inside interfaces and IPv6 addresses on the outside interfaces). • The ASAs have IPv6 inside networks and the outside network is IPv4 (IPv6 addresses on the inside interface and IPv4 addresses on the outside interfaces). • The ASAs have IPv6 inside networks and the outside network is IPv6 (IPv6 addresses on the inside and outside interfaces). Fields • Peer IP Address—Lets you specify an IP address (IPv4 or IPv6) and whether that address is static. • Connection Name—Specifies the name assigned to this connection profile. For the Edit function, this field is display-only. You can specify that the connection name is the same as the IP address specified in the Peer IP Address field. • Interface—Selects the interface to use for this connection. • Protected Networks—Selects or specifies the local and remote network protected for this connection. – IP Address Type—Specifies the address is an IPv4 or IPv6 address. – Local Network—Specifies the IP address of the local network. – ...—Opens the Browse Local Network dialog box, in which you can select a local network. – Remote Network—Specifies the IP address of the remote network. • IPsec Enabling—Specifies the group policy for this connection profile and the key exchange protocol specified in that policy: – Group Policy Name—Specifies the group policy associated with this connection profile. – Manage—Opens the Browse Remote Network dialog box, in which you can select a remote network. – Enable IKEv1—Enables the key exchange protocol IKEv1 in the specified group policy. – Enable IKEv2—Enables the key exchange protocol IKEv2 in the specified group policy. • IKEv1 Settings tab—Specifies authentication and encryption settings for IKEv1: – Pre-shared Key—Specify the value of the pre-shared key for the tunnel group. The maximum length of the pre-shared key is 128 characters. Cisco ASA Series VPN ASDM Configuration Guide 4-85 Chapter 4 General VPN Setup Mapping Certificates to IPsec or SSL VPN Connection Profiles – Device Certificate—Specifies the name of the identity certificate, if available, to use for authentication. – Manage—Opens the Manage Identity Certificates dialog box, on which you can see the certificates that are already configured, add new certificates, show details for a certificate, and edit or delete a certificate. – IKE Policy—Specifies one or more encryption algorithms to use for the IKE proposal. – Manage—Opens the Configure IKEv1 Proposals dialog box. – IPsec Proposal—Specifies one or more encryption algorithms to use for the IPsec IKEv1 proposal. • IKEv2 Settings tab—Specifies authentication and encryption settings for IKEv2: – Local Pre-shared Key—Specify the value of the pre-shared key for the tunnel group. The maximum length of the pre-shared key is 128 characters. – Local Device Certificate—Specifies the name of the identity certificate, if available, to use for authentication. – Manage—Opens the Manage Identity Certificates dialog box, on which you can see the certificates that are already configured, add new certificates, show details for a certificate, and edit or delete a certificate. – Remote Peer Pre-shared Key—Specify the value of the remote peer pre-shared key for the tunnel group. The maximum length of the pre-shared key is 128 characters. – Remote Peer Certificate Authentication—Check Allowed to allow certificate authentication for IKEv2 connections for this connection profile. – Manage—Opens the Manage CA Certificates dialog where you can view certificates and add new ones. – IKE Policy—Specifies one or more encryption algorithms to use for the IKE proposal. – Manage—Opens the Configure IKEv1 Proposals dialog box. – IPsec Proposal—Specifies one or more encryption algorithms to use for the IPsec IKEv1 proposal. – Select—Opens the Select IPsec Proposals (Transform Sets) dialog box, where you can assign a proposal to the connection profile for IKEv2 connections. Adding or Editing a Site-to-Site Tunnel Group You can get to this panel through various paths. The Add or Edit IPsec Site-to-Site Tunnel Group dialog box lets you specify attributes for the IPsec site-to-site connection that you are adding. In addition, you can select IKE peer and user authentication parameters, configure IKE keepalive monitoring, and select the default group policy. Fields • Name—Specifies the name assigned to this tunnel group. For the Edit function, this field is display-only. • IKE Authentication—Specifies the pre-shared key and Identity certificate parameters to use when authenticating an IKE peer. – Pre-shared Key—Specify the value of the pre-shared key for the tunnel group. The maximum length of the pre-shared key is 128 characters. Cisco ASA Series VPN ASDM Configuration Guide 4-86 Chapter 4 General VPN Setup Mapping Certificates to IPsec or SSL VPN Connection Profiles – Identity Certificate—Specifies the name of the ID certificate to use for authentication, if available. – Manage—Opens the Manage Identity Certificates dialog box, on which you can see the certificates that are already configured, add new certificates, show details for a certificate, and edit or delete a certificate. – IKE Peer ID Validation—Specifies whether to check IKE peer ID validation. The default is Required. • IPsec Enabling—Specifies the group policy for this connection profile and the key exchange protocol specified in that policy: – Group Policy Name—Specifies the group policy associated with this connection profile. – Manage—Opens the Browse Remote Network dialog box, in which you can select a remote network. – Enable IKEv1—Enables the key exchange protocol IKEv1 in the specified group policy. – Enable IKEv2—Enables the key exchange protocol IKEv2 in the specified group policy. • IKEv1 Settings tab—Specifies authentication and encryption settings for IKEv1: – Pre-shared Key—Specify the value of the pre-shared key for the tunnel group. The maximum length of the pre-shared key is 128 characters. – Device Certificate—Specifies the name of the identity certificate, if available, to use for authentication. – Manage—Opens the Manage Identity Certificates dialog box, on which you can see the certificates that are already configured, add new certificates, show details for a certificate, and edit or delete a certificate. – IKE Policy—Specifies one or more encryption algorithms to use for the IKE proposal. – Manage—Opens the Configure IKEv1 Proposals dialog box. – IPsec Proposal—Specifies one or more encryption algorithms to use for the IPsec IKEv1 proposal. • IKEv2 Settings tab—Specifies authentication and encryption settings for IKEv2: – Local Pre-shared Key—Specify the value of the pre-shared key for the tunnel group. The maximum length of the pre-shared key is 128 characters. – Local Device Certificate—Specifies the name of the identity certificate, if available, to use for authentication. – Manage—Opens the Manage Identity Certificates dialog box, on which you can see the certificates that are already configured, add new certificates, show details for a certificate, and edit or delete a certificate. – Remote Peer Pre-shared Key—Specify the value of the remote peer pre-shared key for the tunnel group. The maximum length of the pre-shared key is 128 characters. – Remote Peer Certificate Authentication—Check Allowed to allow certificate authentication for IKEv2 connections for this connection profile. – Manage—Opens the Manage CA Certificates dialog where you can view certificates and add new ones. – IKE Policy—Specifies one or more encryption algorithms to use for the IKE proposal. – Manage—Opens the Configure IKEv1 Proposals dialog box. Cisco ASA Series VPN ASDM Configuration Guide 4-87 Chapter 4 General VPN Setup Mapping Certificates to IPsec or SSL VPN Connection Profiles – IPsec Proposal—Specifies one or more encryption algorithms to use for the IPsec IKEv1 proposal. – Select—Opens the Select IPsec Proposals (Transform Sets) dialog box, where you can assign a proposal to the connection profile for IKEv2 connections. • IKE Keepalive —Enables and configures IKE keepalive monitoring. You can select only one of the following attributes. – Disable Keep Alives—Enables or disables IKE keep alives. – Monitor Keep Alives—Enables or disables IKE keep alive monitoring. Selecting this option makes available the Confidence Interval and Retry Interval fields. – Confidence Interval—Specifies the IKE keep alive confidence interval. This is the number of seconds the ASA should allow a peer to idle before beginning keepalive monitoring. The minimum is 10 seconds; the maximum is 300 seconds. The default for a remote access group is 10 seconds. – Retry Interval—Specifies number of seconds to wait between IKE keep alive retries. The default is 2 seconds. – Head end will never initiate keepalive monitoring—Specifies that the central-site ASA never initiates keepalive monitoring. Crypto Map Entry In this dialog box, specify crypto parameters for the Connection Profile. Fields • Priority—A unique priority (1 through 65,543, with 1 the highest priority). When IKE negotiation begins, the peer that initiates the negotiation sends all of its policies to the remote peer, and the remote peer searches for a match with its own policies, in priority order. • Perfect Forward Secrecy—Ensures that the key for a given IPsec SA was not derived from any other secret (like some other keys). If someone were to break a key, PFS ensures that the attacker would not be able to derive any other key. If you enable PFS, the Diffie-Hellman Group list becomes active. – Diffie-Hellman Group—An identifier which the two IPsec peers use to derive a shared secret without transmitting it to each other. The choices are Group 1 (768-bits), Group 2 (1024-bits), and Group 5 (1536-bits). • Enable NAT-T— Enables NAT Traversal (NAT-T) for this policy, which lets IPsec peers establish both remote access and LAN-to-LAN connections through a NAT device. • Enable Reverse Route Injection—Provides the ability for static routes to be automatically inserted into the routing process for those networks and hosts that are protected by a remote tunnel endpoint. • Security Association Lifetime—Configures the duration of a Security Association (SA). This parameter specifies how to measure the lifetime of the IPsec SA keys, which is how long the IPsec SA lasts until it expires and must be renegotiated with new keys. – Time—Specifies the SA lifetime in terms of hours (hh), minutes (mm) and seconds (ss). – Traffic Volume—Defines the SA lifetime in terms of kilobytes of traffic. Enter the number of kilobytes of payload data after which the IPsec SA expires. Minimum is 100 KB, default is 10000 KB, maximum is 2147483647 KB. Cisco ASA Series VPN ASDM Configuration Guide 4-88 Chapter 4 General VPN Setup Mapping Certificates to IPsec or SSL VPN Connection Profiles Crypto Map Entry for Static Peer Address In this dialog box, specify crypto parameters for the Connection Profile when the Peer IP Address is a static address. Fields • Priority—A unique priority (1 through 65,543, with 1 the highest priority). When IKE negotiation begins, the peer that initiates the negotiation sends all of its policies to the remote peer, and the remote peer searches for a match with its own policies, in priority order. • Perfect Forward Secrecy—Ensures that the key for a given IPsec SA was not derived from any other secret (like some other keys). If someone were to break a key, PFS ensures that the attacker would not be able to derive any other key. If you enable PFS, the Diffie-Hellman Group list becomes active. – Diffie-Hellman Group—An identifier which the two IPsec peers use to derive a shared secret without transmitting it to each other. The choices are Group 1 (768-bits), Group 2 (1024-bits), and Group 5 (1536-bits). • Enable NAT-T— Enables NAT Traversal (NAT-T) for this policy, which lets IPsec peers establish both remote access and LAN-to-LAN connections through a NAT device. • Enable Reverse Route Injection—Provides the ability for static routes to be automatically inserted into the routing process for those networks and hosts that are protected by a remote tunnel endpoint. • Security Association Lifetime—Configures the duration of a Security Association (SA). This parameter specifies how to measure the lifetime of the IPsec SA keys, which is how long the IPsec SA lasts until it expires and must be renegotiated with new keys. – Time—Specifies the SA lifetime in terms of hours (hh), minutes (mm) and seconds (ss). – Traffic Volume—Defines the SA lifetime in terms of kilobytes of traffic. Enter the number of kilobytes of payload data after which the IPsec SA expires. Minimum is 100 KB, default is 10000 KB, maximum is 2147483647 KB. • Static Crypto Map Entry Parameters—Configure these additional parameters when the Peer IP Address is specified as Static: – Connection Type—Specify the allowed negotiation as bidirectional, answer-only, or originate-only. – Send ID Cert. Chain—Enables transmission of the entire certificate chain. – IKE Negotiation Mode—Sets the mode for exchanging key information for setting up the SAs, Main or Aggressive. It also sets the mode that the initiator of the negotiation uses; the responder auto-negotiates. Aggressive Mode is faster, using fewer packets and fewer exchanges, but it does not protect the identity of the communicating parties. Main Mode is slower, using more packets and more exchanges, but it protects the identities of the communicating parties. This mode is more secure and it is the default selection. If you select Aggressive, the Diffie-Hellman Group list becomes active. – Diffie-Hellman Group—An identifier which the two IPsec peers use to derive a shared secret without transmitting it to each other. The choices are Group 1 (768-bits), Group 2 (1024-bits), and Group 5 (1536-bits). Cisco ASA Series VPN ASDM Configuration Guide 4-89 Chapter 4 General VPN Setup Mapping Certificates to IPsec or SSL VPN Connection Profiles Managing CA Certificates Clicking Manage under IKE Peer Authentication opens the Manage CA Certificates dialog box. Use this dialog box to view, add, edit, and delete entries on the list of CA certificates available for IKE peer authentication. The Manage CA Certificates dialog box lists information about currently configured certificates, including information about whom the certificate was issued to, who issued the certificate, when the certificate expires, and usage data. Fields • Add or Edit—Opens the Install Certificate dialog box or the Edit Certificate dialog box, which let you specify information about and install a certificate. • Show Details—Displays detailed information about a certificate that you select in the table. • Delete—Removes the selected certificate from the table. There is no confirmation or undo. Install Certificate Use this dialog box to install a new CA certificate. You can get the certificate in one of the following ways: • Install from a file by browsing to the certificate file. • Paste the previously acquired certificate text in PEM format into the box on this dialog box. • Use SCEP—Specifies the use of the Simple Certificate Enrollment Protocol (SCEP) Add-on for Certificate Services runs on the Windows Server 2003 family. It provides support for the SCEP protocol, which allows Cisco routers and other intermediate network devices to obtain certificates. – SCEP URL: http://—Specifies the URL from which to download SCEP information. – Retry Period—Specifies the number of minutes that must elapse between SCEP queries. – Retry Count—Specifies the maximum number of retries allowed. • More Options—Opens the Configure Options for CA Certificate dialog box. : Configure Options for CA Certificate Use this dialog box to specify details about retrieving CA Certificates for this IPsec remote access connection. The dialog boxes on this dialog box are: Revocation Check, CRL Retrieval Policy, CRL Retrieval Method, OCSP Rules, and Advanced. Revocation Check Dialog Box Use this dialog box to specify information about CA Certificate revocation checking. Fields • The radio buttons specify whether to check certificates for revocation. The values of these buttons are as follows: Cisco ASA Series VPN ASDM Configuration Guide 4-90 Chapter 4 General VPN Setup Mapping Certificates to IPsec or SSL VPN Connection Profiles – Do not check certificates for revocation – Check Certificates for revocation • Revocation Methods area—Lets you specify the method–CRL or OCSP–to use for revocation checking, a nd the order in which to use these methods. You can choose either or both methods. Add/Edit Remote Access Connections > Advanced > General Use this dialog box to specify whether to strip the realm and group from the username before passing them to the AAA server, and to specify password management parameters. Fields • Note Strip the realm from username before passing it on to the AAA server—Enables or disables stripping the realm (administrative domain) from the username before passing the username on to the AAA server. Check the Strip Realm check box to remove the realm qualifier of the username during authentication. You can append the realm name to the username for AAA: authorization, authentication and accounting. The only valid delimiter for a realm is the @ character. The format is username@realm, for example, JaneDoe@example.com. If you check this Strip Realm check box, authentication is based on the username alone. Otherwise, authentication is based on the full username@realm string. You must check this box if your server is unable to parse delimiters. You can append both the realm and the group to a username, in which case the ASA uses parameters configured for the group and for the realm for AAA functions. The format for this option is username[@realm]]<#or!>group], for example, JaneDoe@example.com#VPNGroup. If you choose this option, you must use either the # or ! character for the group delimiter because the ASA cannot interpret the @ as a group delimiter if it is also present as the realm delimiter. A Kerberos realm is a special case. The convention in naming a Kerberos realm is to capitalize the DNS domain name associated with the hosts in the Kerberos realm. For example, if users are in the example.com domain, you might call your Kerberos realm EXAMPLE.COM. The ASA does not include support for the user@grouppolicy, as the VPN 3000 Concentrator did. Only the L2TP/IPsec client supports the tunnel switching via user@tunnelgroup. • Strip the group from the username before passing it on to the AAA server—Enables or disables stripping the group name from the username before passing the username on to the AAA server. Check Strip Group to remove the group name from the username during authentication. This option is meaningful only when you have also checked the Enable Group Lookup box. When you append a group name to a username using a delimiter, and enable Group Lookup, the ASA interprets all characters to the left of the delimiter as the username, and those to the right as the group name. Valid group delimiters are the @, #, and ! characters, with the @ character as the default for Group Lookup. You append the group to the username in the format usernamegroup, the possibilities being, for example, JaneDoe@VPNGroup, JaneDoe#VPNGroup, and JaneDoe!VPNGroup. • Password Management—Lets you configure parameters relevant to overriding an account-disabled indication from a AAA server and to notifying users about password expiration. – Override account-disabled indication from AAA server—Overrides an account-disabled indication from a AAA server. Cisco ASA Series VPN ASDM Configuration Guide 4-91 Chapter 4 General VPN Setup Configuring Client Addressing Note Allowing override account-disabled is a potential security risk. – Enable notification upon password expiration to allow user to change password—Checking this check box makes the following two parameters available. You can select either to notify the user at login a specific number of days before the password expires or to notify the user only on the day that the password expires. The default is to notify the user 14 days prior to password expiration and every day thereafter until the user changes the password. The range is 1 through 180 days. Note This does not change the number of days before the password expires, but rather, it enables the notification. If you select this option, you must also specify the number of days. In either case, and, if the password expires without being changed, the ASA offers the user the opportunity to change the password. If the current password has not yet expired, the user can still log in using that password. This parameter is valid for AAA servers that support such notification; that is, RADIUS, RADIUS with an NT server, and LDAP servers. The ASA ignores this command if RADIUS or LDAP authentication has not been configured. This feature requires the use of MS-CHAPv2. Configuring Client Addressing To specify the client IP address assignment policy and assign address pools to all IPsec and SSL VPN connections, open ASDM and select Configuration > Remote Access VPN > Network (Client) Access > IPsec or SSL VPN Connections > Add or Edit > Advanced > Client Addressing. The Add IPsec Remote Access Connection or Add SSL VPN Access Connection opens. Use this dialog box to add address pools and assign them to interfaces, and view, edit, or delete them. The table at the bottom of the dialog box lists the configured interface-specific address pools. To understand the fields in this dialog box or its descendent dialog boxes, see the sections that follow this one. You can view or change the configuration of address pools and their assignment to interfaces, as follows: • To view or change the configuration of address pools, click Add or Edit in the Add IPsec Remote Access Connection or Add SSL VPN Access Connection dialog box. The Assign Address Pools to Interface dialog box opens. This dialog box lets you assign IP address pools to the interfaces configured on the ASA. Click Select. The Select Address Pools dialog box opens. Use this dialog box to view the configuration of address pools. You can change their address pool configuration as follows: – To add an address pool to the ASA, choose Add. The Add IP Pool dialog box opens. – To change the configuration of an address pool on the ASA, choose Edit. The Edit IP Pool dialog box opens if the addresses in the pool are not in use. Note You cannot modify an address pool if it is already in use. If you click Edit and the address pool is in use, ASDM displays an error message and lists the connection names and usernames that are using the addresses in the pool. Cisco ASA Series VPN ASDM Configuration Guide 4-92 Chapter 4 General VPN Setup Configuring Client Addressing – To remove address pool on the ASA, select the entry in the table and click Delete. Note You cannot remove an address pool if it is already in use. If you click Delete and the address pool is in use, ASDM displays an error message and lists the connection names that are using the addresses in the pool. • To assign address pools to an interface, click Add in the Add IPsec Remote Access Connection or Add SSL VPN Access Connection dialog box. The Assign Address Pools to Interface dialog box opens. Select the interface to be assigned an address pool. Click Select next to the Address Pools field. The Select Address Pools dialog box opens. Double-click each unassigned pool you want to assign to the interface or choose each unassigned pool and click Assign. The adjacent field displays the list of pool assignments. Click OK to populate the Address Pools field with the names of these address pools, then OK again to complete the configuration of the assignment. • To change the address pools assigned to an interface, double-click the interface, or choose the interface in the Add IPsec Remote Access Connection or Add SSL VPN Access Connection dialog box and click Edit. The Assign Address Pools to Interface dialog box opens. To remove address pools, double-click each pool name and press the Delete button on the keyboard. Click Select next to the Address Pools field if you want to assign additional fields to the interface. The Select Address Pools dialog box opens. Note that the Assign field displays the address pool names that remained assigned to the interface. Double-click each unassigned pool you want to add to the interface. The Assign field updates the list of pool assignments. Click OK to revise the Address Pools field with the names of these address pools, then OK again to complete the configuration of the assignment. • To remove an entry from the Add IPsec Remote Access Connection or Add SSL VPN Access Connection dialog box, choose the entry and click Delete. The Add IPsec Remote Access Connection and Add SSL VPN Access Connection dialog boxes and their descendent dialog boxes are identical. Use the following sections to understand or assign values to the fields in these dialog boxes: • Add IPsec Remote Access Connection and Add SSL VPN Access Connection • Assign Address Pools to Interface • Select Address Pools • Add or Edit IP Pool Add IPsec Remote Access Connection and Add SSL VPN Access Connection To access the Add IPsec Remote Access Connection and Add SSL VPN Access Connection dialog boxes, choose Config > Remote Access VPN > Network (Client) Access > IPsec or SSL VPN Connections > Add or Edit > Advanced > Client Addressing. Fields Use the following descriptions to assign values to the fields in this dialog box: • Global Client Address Assignment Policy—Configures a policy that affects all IPsec and SSL VPN Client connections (including AnyConnect client connections). The ASA uses the selected sources in order, until it finds an address: – Use authentication server—Specifies that the ASA should attempt to use the authentication server as the source for a client address. – Use DHCP—Specifies that the ASA should attempt to use DHCP as the source for a client address. Cisco ASA Series VPN ASDM Configuration Guide 4-93 Chapter 4 General VPN Setup Configuring Client Addressing – Use address pool—Specifies that the ASA should attempt to use address pools as the source for a client address. • Interface-Specific Address Pools—Lists the configured interface-specific address pools. Assign Address Pools to Interface Use the Assign Address Pools to Interface dialog box to select an interface and assign one or more address pools to that interface. To access this dialog box, choose Config > Remote Access VPN > Network (Client) Access > IPsec or SSL VPN Connections > Add or Edit > Advanced > Client Addressing > Add or Edit. Fields Use the following descriptions to assign values to the fields in this dialog box: • Interface—Select the interface to which you want to assign an address pool. The default is DMZ. • Address Pools—Specify an address pool to assign to the specified interface. • Select—Opens the Select Address Pools dialog box, in which you can select one or more address pools to assign to this interface. Your selection appears in the Address Pools field of the Assign Address Pools to Interface dialog box. Select Address Pools The Select Address Pools dialog box shows the pool name, starting and ending addresses, and subnet mask of address pools available for client address assignment and lets you add, edit, or delete entries from that list. To access this dialog box, choose Config > Remote Access VPN > Network (Client) Access > IPsec or SSL VPN Connections > Add or Edit > Advanced > Client Addressing > Add or Edit > Select. Fields Use the following descriptions to assign values to the fields in this dialog box: • Add—Opens the Add IP Pool dialog box, on which you can configure a new IP address pool. • Edit—Opens the Edit IP Pool dialog box, on which you can modify a selected IP address pool. • Delete—Removes the selected address pool. There is no confirmation or undo. • Assign—Displays the address pool names that remained assigned to the interface. Double-click each unassigned pool you want to add to the interface. The Assign field updates the list of pool assignments. Add or Edit IP Pool The Add or Edit IP Pool dialog box lets you specify or modify a range of IP addresses for client address assignment. To access this dialog box, choose Config > Remote Access VPN > Network (Client) Access > IPsec or SSL VPN Connections > Add or Edit > Advanced > Client Addressing > Add or Edit > Select > Add or Edit. Fields Use the following descriptions to assign values to the fields in this dialog box: • Name—Specifies the name assigned to the IP address pool. • Starting IP Address—Specifies the first IP address in the pool. • Ending IP Address—Specifies the last IP address in the pool. Cisco ASA Series VPN ASDM Configuration Guide 4-94 Chapter 4 General VPN Setup Configuring Client Addressing • Subnet Mask—Selects the subnet mask to apply to the addresses in the pool. Add/Edit Connection Profile > General > Authentication You can get to this panel through various paths. This dialog box is available for IPsec on Remote Access and Site-to-Site tunnel groups. The settings on this dialog box apply to the tunnel group globally across the ASA. To set authentication server group settings per interface, click Advanced. This dialog box lets you configure the following attributes: • Authentication Server Group—Lists the available authentication server groups, including the LOCAL group (the default). You can also select None. Selecting something other than None or Local makes available the Use LOCAL if Server Group Fails check box. To set the authentication server group per interface, click Advanced. • Use LOCAL if Server Group fails—Enables or disables fallback to the LOCAL database if the group specified by the Authentication Server Group attribute fails. Add/Edit SSL VPN Connection > General > Authorization You can get to this panel through various paths. The settings on this dialog box apply to the connection (tunnel group) globally across the ASA. This dialog box lets you configure the following attributes: • Authorization Server Group—Lists the available authorization server groups, including the LOCAL group. You can also select None (the default). Selecting something other than None makes available the check box for Users must exist in authorization database to connect. • Users must exist in the authorization database to connect—Tells the ASA to allow only users in the authorization database to connect. By default this feature is disabled. You must have a configured authorization server to use this feature. • Interface-Specific Authorization Server Groups—(Optional) Lets you configure authorization server groups on a per-interface basis. Interface-specific authorization server groups take precedence over the global server group. If you do not explicitly configure interface-specific authorization, authorization takes place only at the group level. – Interface—Select the interface on which to perform authorization. The standard interfaces are outside (the default), inside, and DMZ. If you have configured other interfaces, they also appear in the list. – Server Group—Select an available, previously configured authorization server group or group of servers, including the LOCAL group. You can associate a server group with more than one interface. – Add—Click Add to add the interface/server group setting to the table and remove the interface from the available list. – Remove—Click Remove to remove the interface/server group from the table and restore the interface to the available list. • Authorization Settings—Lets you set values for usernames that the ASA recognizes for authorization. This applies to users that authenticate with digital certificates and require LDAP or RADIUS authorization. – Use the entire DN as the username—Allows the use of the entire Distinguished Name (DN) as the username. Cisco ASA Series VPN ASDM Configuration Guide 4-95 Chapter 4 General VPN Setup Configuring Client Addressing – Specify individual DN fields as the username—Enables the use of individual DN fields as the username. – Primary DN Field—Lists all of the DN field identifiers for your selection. DN Field Definition Country (C) Two-letter country abbreviation. These codes conform to ISO 3166 country abbreviations. Common Name (CN) Name of a person, system, or other entity. This is the lowest (most specific) level in the identification hierarchy. DN Qualifier (DNQ) Specific DN attribute. E-mail Address (EA) E-mail address of the person, system or entity that owns the certificate. Generational Qualifier (GENQ) Generational qualifier such as Jr., Sr., or III. Given Name (GN) First name of the certificate owner. Initials (I) First letters of each part of the certificate owner’s name. Locality (L) City or town where the organization is located. Name (N) Name of the certificate owner. Organization (O) Name of the company, institution, agency, association, or other entity. Organizational Unit (OU) Subgroup within the organization. Serial Number (SER) Serial number of the certificate. Surname (SN) Family name or last name of the certificate owner. State/Province (S/P) State or province where the organization is located. Title (T) Title of the certificate owner, such as Dr. User ID (UID) Identification number of the certificate owner. User Principal Name (UPN) Used with Smart Card certificate authentication. – Secondary DN Field—Lists all of the DN field identifiers (see the foregoing table) for your selection and adds the option None for no selection. Add/Edit SSL VPN Connections > Advanced > Accounting You can get to this panel through various paths. The settings on this dialog box apply to the connection (tunnel group) globally across the ASA. This dialog box lets you configure the following attribute: • Accounting Server Group—Lists the available accounting server groups. You can also select None (the default). LOCAL is not an option. • Manage—Opens the Configure AAA Server Groups dialog box. Cisco ASA Series VPN ASDM Configuration Guide 4-96 Chapter 4 General VPN Setup Configuring Client Addressing Add/Edit Tunnel Group > General > Client Address Assignment You can get to this panel through various paths. To specify whether to use DHCP or address pools for address assignment, go to Configuration > VPN > I P Address Management > Assignment. The Add or Edit Tunnel Group dialog box > General > Client Address Assignment dialog box, lets you configure the following Client Address Assignment attributes: • DHCP Servers—Specifies a DHCP server to use. You can add up to 10 servers, one at a time. – IP Address—Specifies the IP address of a DHCP server. – Add—Adds the specified DHCP server to the list for client address assignment. – Delete—Deletes the specified DHCP server from the list for client address assignment. There is no confirmation or undo. • Address Pools—Lets you specify up to 6 address pools, using the following parameters: – Available Pools—Lists the available, configured address pools you can choose. – Add—Adds the selected address pool to the list for client address assignment. – Remove—Moves the selected address pool from the Assigned Pools list to the Available Pools list. – Assigned Pools—Lists the address pools selected for address assignment. Note To configure interface-specific address pools, click Advanced. Add/Edit Tunnel Group > General > Advanced You can get to this panel through various paths. The Add or Edit Tunnel Group dialog box, General, Advanced dialog box, lets you configure the following interface-specific attributes: • Interface-Specific Authentication Server Groups—Lets you configure an interface and server group for authentication. – Interface—Lists available interfaces for selection. – Server Group—Lists authentication server groups available for this interface. – Use LOCAL if server group fails—Enables or disables fallback to the LOCAL database if the server group fails. – Add—Adds the association between the selected available interface and the authentication server group to the assigned list. – Remove—Moves the selected interface and authentication server group association from the assigned list to the available list. – Interface/Server Group/Use Fallback—Show the selections you have added to the assigned list. • Interface-Specific Client IP Address Pools—-Lets you specify an interface and Client IP address pool. You can have up to 6 pools. – Interface—Lists the available interfaces to add. – Address Pool—Lists address pools available to associate with this interface. – Add—Adds the association between the selected available interface and the client IP address pool to the assigned list. Cisco ASA Series VPN ASDM Configuration Guide 4-97 Chapter 4 General VPN Setup Configuring Client Addressing – Remove—Moves the selected interface/address pool association from the assigned list to the available list. – Interface/Address Pool—Shows the selections you have added to the assigned list. Add/Edit Tunnel Group > IPsec for Remote Access > IPsec Configuration > VPN > General > Tunnel Group > Add/Edit Tunnel Group > IPSec for Remote Access > IPSec Tab On the Add or Edit Tunnel Group dialog box for IPsec for Remote Access, the IPsec dialog box lets you configure or edit IPsec-specific tunnel group parameters. Fields • Pre-shared Key—Lets you specify the value of the pre-shared key for the tunnel group. The maximum length of the pre-shared key is 128 characters. • Trustpoint Name—Selects a trustpoint name, if any trustpoints are configured. A trustpoint is a representation of a certificate authority. A trustpoint contains the identity of the CA, CA-specific configuration parameters, and an association with one enrolled identity certificate. • Authentication Mode—Specifies the authentication mode: none, xauth, or hybrid. – none—Specifies no authentication mode. – xauth—Specifies the use of IKE Extended Authentication mode, which provides the capability of authenticating a user within IKE using TACACS+ or RADIUS. – hybrid—Specifies the use of Hybrid mode, which lets you use digital certificates for security appliance authentication and a different, legacy method—such as RADIUS, TACACS+ or SecurID—for remote VPN user authentication. This mode breaks phase 1 of the Internet Key Exchange (IKE) into the following steps, together called hybrid authentication: Note 1. The security appliance authenticates to the remote VPN user with standard public key techniques. This establishes an IKE security association that is unidirectionally authenticated. 2. An extended authentication (xauth) exchange then authenticates the remote VPN user. This extended authentication can use one of the supported legacy authentication methods. Before setting the authentication type to hybrid, you must configure the authentication server and create a pre-shared key. • IKE Peer ID Validation—Selects whether IKE peer ID validation is ignored, required, or checked only if supported by a certificate. • Enable sending certificate chain—Enables or disables sending the entire certificate chain. This action includes the root certificate and any subordinate CA certificates in the transmission. • ISAKMP Keep Alive—Enables and configures ISAKMP keep alive monitoring. – Disable Keep Alives—Enables or disables ISAKMP keep alives. – Monitor Keep Alives—Enables or disables ISAKMP keep alive monitoring. Selecting this option makes available the Confidence Interval and Retry Interval fields. – Confidence Interval—Specifies the ISAKMP keep alive confidence interval. This is the number of seconds the ASA should allow a peer to idle before beginning keepalive monitoring. The minimum is 10 seconds; the maximum is 300 seconds. The default for a remote access group is 300 seconds. Cisco ASA Series VPN ASDM Configuration Guide 4-98 Chapter 4 General VPN Setup Configuring Client Addressing – Retry Interval—Specifies number of seconds to wait between ISAKMP keep alive retries. The default is 2 seconds. – Head end will never initiate keepalive monitoring—Specifies that the central-site ASA never initiates keepalive monitoring. • Interface-Specific Authentication Mode—Specifies the authentication mode on a per-interface basis. – Interface—Lets you select the interface name. The default interfaces are inside and outside, but if you have configured a different interface name, that name also appears in the list. – Authentication Mode—Lets you select the authentication mode, none, xauth, or hybrid, as above. – Interface/Authentication Mode table—Shows the interface names and their associated authentication modes that are selected. – Add—Adds an interface/authentication mode pair selection to the Interface/Authentication Modes table. – Remove—Removes an interface/authentication mode pair selection from the Interface/Authentication Modes table. • Client VPN Software Update Table—Lists the client type, VPN Client revisions, and image URL for each client VPN software package installed. For each client type, you can specify the acceptable client software revisions and the URL or IP address from which to download software upgrades, if necessary. The client update mechanism (described in detail under the Client Update dialog box) uses this information to determine whether the software each VPN client is running is at an appropriate revision level and, if appropriate, to provide a notification message and an update mechanism to clients that are running outdated software. – Client Type—Identifies the VPN client type. – VPN Client Revisions—Specifies the acceptable revision level of the VPN client. – Image URL—Specifies the URL or IP address from which the correct VPN client software image can be downloaded. For dialog boxes-based VPN clients, the URL must be of the form http:// or https://. For ASA 5505 in client mode or VPN 3002 hardware clients, the URL must be of the form tftp://. Add/Edit Tunnel Group for Site-to-Site VPN Configuration > VPN > General > Tunnel Group > Add/Edit Tunnel Group > IPSec for Remote Access > IPSec Tab The Add or Edit Tunnel Group dialog box lets you configure or edit tunnel group parameters for this Site-to-Site connection profile. Fields • Certificate Settings—Sets the following certificate chain and IKE peer validation attributes: – Send certificate chain—Enables or disables sending the entire certificate chain. This action includes the root certificate and any subordinate CA certificates in the transmission. – IKE Peer ID Validation—Selects whether IKE peer ID validation is ignored, required, or checked only if supported by a certificate. • IKE Keep Alive—Enables and configures IKE (ISAKMP) keepalive monitoring. – Disable Keepalives—Enables or disables IKE keep alives. Cisco ASA Series VPN ASDM Configuration Guide 4-99 Chapter 4 General VPN Setup Configuring Client Addressing – Monitor Keepalives—Enables or disables IKE keep alive monitoring. Selecting this option makes available the Confidence Interval and Retry Interval fields. – Confidence Interval—Specifies the IKE keepalive confidence interval. This is the number of seconds the ASA should allow a peer to idle before beginning keepalive monitoring. The minimum is 10 seconds; the maximum is 300 seconds. The default for a remote access group is 300 seconds. – Retry Interval—Specifies number of seconds to wait between IKE keepalive retries. The default is 2 seconds. – Head end will never initiate keepalive monitoring—Specifies that the central-site ASA never initiates keepalive monitoring. • Default Group Policy—Specifies the following group-policy attributes: – Group Policy—Selects a group policy to use as the default group policy. The default value is DfltGrpPolicy. – Manage—Opens the Configure Group Policies dialog box. – IPsec Protocol—Enables or disables the use of the IPsec protocol for this connection profile. Add/Edit Tunnel Group > PPP Configuration > VPN > General > Tunnel Group > Add/Edit Tunnel Group > PPP Tab On the Add or Edit Tunnel Group dialog box for a IPsec remote access tunnel group, the PPP dialog box lets you configure or edit the authentication protocols permitted of a PPP connection. This dialog box applies only to IPsec remote access tunnel groups. Fields • CHAP—Enables the use of the CHAP protocol for a PPP connection. • MS-CHAP-V1—Enables the use of the MS-CHAP-V1 protocol for a PPP connection. • MS-CHAP-V2—Enables the use of the MS-CHAP-V2 protocol for a PPP connection. • PAP—Enables the use of the PAP protocol for a PPP connection. • EAP-PROXY—Enables the use of the EAP-PROXY protocol for a PPP connection. EAP refers to the Extensible Authentication protocol. Add/Edit Tunnel Group > IPsec for LAN to LAN Access > General > Basic Configuration > VPN > General > Tunnel Group > Add/Edit Tunnel Group > IPSec for LAN to LAN Access > General Tab > Basic Tab On the Add or Edit Tunnel Group dialog box for Site-to-Site Remote Access, the General, Basic dialog box you can specify a name for the tunnel group that you are adding (Add function only) and select the group policy. On the Edit Tunnel Group dialog box, the General dialog box displays the name and type of the tunnel group you are modifying. Fields • Name—Specifies the name assigned to this tunnel group. For the Edit function, this field is display-only. Cisco ASA Series VPN ASDM Configuration Guide 4-100 Chapter 4 General VPN Setup Configuring Client Addressing • Type—(Display-only) Displays the type of tunnel group you are adding or editing. The contents of this field depend on your selection on the previous dialog box. • Group Policy—Lists the currently configured group policies. The default value is the default group policy, DfltGrpPolicy. • Strip the realm (administrative domain) from the username before passing it on to the AAA server—Enables or disables stripping the realm from the username before passing the username on to the AAA server. Check the Strip Realm check box to remove the realm qualifier of the username during authentication. You can append the realm name to the username for AAA: authorization, authentication and accounting. The only valid delimiter for a realm is the @ character. The format is username@realm, for example, JaneDoe@example.com. If you check this Strip Realm check box, authentication is based on the username alone. Otherwise, authentication is based on the full username@realm string. You must check this box if your server is unable to parse delimiters. Note You can append both the realm and the group to a username, in which case the ASA uses parameters configured for the group and for the realm for AAA functions. The format for this option is username[@realm]]<#or!>group], for example, JaneDoe@example.com#VPNGroup. If you choose this option, you must use either the # or ! character for the group delimiter because the ASA cannot interpret the @ as a group delimiter if it is also present as the realm delimiter. A Kerberos realm is a special case. The convention in naming a Kerberos realm is to capitalize the DNS domain name associated with the hosts in the Kerberos realm. For example, if users are in the example.com domain, you might call your Kerberos realm EXAMPLE.COM. The ASA does not include support for the user@grouppolicy, as the VPN 3000 Concentrator did. Only the L2TP/IPsec client supports the tunnel switching via user@tunnelgroup. • Strip the group from the username before passing it on to the AAA server—Enables or disables stripping the group name from the username before passing the username on to the AAA server. Check Strip Group to remove the group name from the username during authentication. This option is meaningful only when you have also checked the Enable Group Lookup box. When you append a group name to a username using a delimiter, and enable Group Lookup, the ASA interprets all characters to the left of the delimiter as the username, and those to the right as the group name. Valid group delimiters are the @, #, and ! characters, with the @ character as the default for Group Lookup. You append the group to the username in the format usernamegroup, the possibilities being, for example, JaneDoe@VPNGroup, JaneDoe#VPNGroup, and JaneDoe!VPNGroup. • Password Management—Lets you configure parameters relevant to overriding an account-disabled indication from a AAA server and to notifying users about password expiration. – Override account-disabled indication from AAA server—Overrides an account-disabled indication from a AAA server. Note Allowing override account-disabled is a potential security risk. – Enable notification upon password expiration to allow user to change password—Checking this check box makes the following two parameters available. If you do not also check the Enable notification prior to expiration check box, the user receives notification only after the password has expired. Cisco ASA Series VPN ASDM Configuration Guide 4-101 Chapter 4 General VPN Setup Configuring Client Addressing – Enable notification prior to expiration—When you check this option, the ASA notifies the remote user at login that the current password is about to expire or has expired, then offers the user the opportunity to change the password. If the current password has not yet expired, the user can still log in using that password. This parameter is valid for AAA servers that support such notification; that is, RADIUS, RADIUS with an NT server, and LDAP servers. The ASA ignores this command if RADIUS or LDAP authentication has not been configured. Note that this does not change the number of days before the password expires, but rather, it enables the notification. If you check this check box, you must also specify the number of days. – Notify...days prior to expiration—Specifies the number of days before the current password expires to notify the user of the pending expiration. The range is 1 through 180 days. Add/Edit Tunnel Group > IPsec for LAN to LAN Access > IPsec Configuration > VPN > General > Tunnel Group > Add/Edit Tunnel Group > IPSec for LAN to LAN Access > IPSec Tab The Add or Edit Tunnel Group dialog box for IPsec for Site-to-Site access, IPsec dialog box, lets you configure or edit IPsec Site-to-Site-specific tunnel group parameters. Fields • Name—Specifies the name assigned to this tunnel group. For the Edit function, this field is display-only. • Type—(Display-only) Displays the type of tunnel group you are adding or editing. The contents of this field depend on your selection on the previous dialog box. • Pre-shared Key—Lets you specify the value of the pre-shared key for the tunnel group. The maximum length of the pre-shared key is 128 characters. • Trustpoint Name—Selects a trustpoint name, if any trustpoints are configured. A trustpoint is a representation of a certificate authority. A trustpoint contains the identity of the CA, CA-specific configuration parameters, and an association with one enrolled identity certificate. • Authentication Mode—Specifies the authentication mode: none, xauth, or hybrid. – none—Specifies no authentication mode. – xauth—Specifies the use of IKE Extended Authentication mode, which provides the capability of authenticating a user within IKE using TACACS+ or RADIUS. – hybrid—Specifies the use of Hybrid mode, which lets you use digital certificates for security appliance authentication and a different, legacy method—such as RADIUS, TACACS+ or SecurID—for remote VPN user authentication. This mode breaks phase 1 of the Internet Key Exchange (IKE) into the following steps, together called hybrid authentication: Note • 1. The security appliance authenticates to the remote VPN user with standard public key techniques. This establishes an IKE security association that is unidirectionally authenticated. 2. An extended authentication (xauth) exchange then authenticates the remote VPN user. This extended authentication can use one of the supported legacy authentication methods. Before setting the authentication type to hybrid, you must configure the authentication server and create a pre-shared key. IKE Peer ID Validation—Selects whether IKE peer ID validation is ignored, required, or checked only if supported by a certificate. Cisco ASA Series VPN ASDM Configuration Guide 4-102 Chapter 4 General VPN Setup Configuring Client Addressing • Enable sending certificate chain—Enables or disables sending the entire certificate chain. This action includes the root certificate and any subordinate CA certificates in the transmission. • ISAKMP Keep Alive—Enables and configures ISAKMP keep alive monitoring. – Disable Keep Alives—Enables or disables ISAKMP keep alives. – Monitor Keep Alives—Enables or disables ISAKMP keep alive monitoring. Selecting this option makes available the Confidence Interval and Retry Interval fields. – Confidence Interval—Specifies the ISAKMP keep alive confidence interval. This is the number of seconds the ASA should allow a peer to idle before beginning keepalive monitoring. The minimum is 10 seconds; the maximum is 300 seconds. The default for a remote access group is 300 seconds. – Retry Interval—Specifies number of seconds to wait between ISAKMP keep alive retries. The default is 2 seconds. – Head end will never initiate keepalive monitoring—Specifies that the central-site ASA never initiates keepalive monitoring. • Interface-Specific Authentication Mode—Specifies the authentication mode on a per-interface basis. – Interface—Lets you select the interface name. The default interfaces are inside and outside, but if you have configured a different interface name, that name also appears in the list. – Authentication Mode—Lets you select the authentication mode, none, xauth, or hybrid, as above. – Interface/Authentication Mode table—Shows the interface names and their associated authentication modes that are selected. – Add—Adds an interface/authentication mode pair selection to the Interface/Authentication Modes table. – Remove—Removes an interface/authentication mode pair selection from the Interface/Authentication Modes table. • Client VPN Software Update Table—Lists the client type, VPN Client revisions, and image URL for each client VPN software package installed. For each client type, you can specify the acceptable client software revisions and the URL or IP address from which to download software upgrades, if necessary. The client update mechanism (described in detail under the Client Update dialog box) uses this information to determine whether the software each VPN client is running is at an appropriate revision level and, if appropriate, to provide a notification message and an update mechanism to clients that are running outdated software. – Client Type—Identifies the VPN client type. – VPN Client Revisions—Specifies the acceptable revision level of the VPN client. – Image URL—Specifies the URL or IP address from which the correct VPN client software image can be downloaded. For Windows-based VPN clients, the URL must be of the form http:// or https://. For ASA 5505 in client mode or VPN 3002 hardware clients, the URL must be of the form tftp://. Clientless SSL VPN Access > Connection Profiles > Add/Edit > General > Basic Configuration > VPN > General > Tunnel Group > Add/Edit> WebVPN Access > General Tab > Basic Tab Cisco ASA Series VPN ASDM Configuration Guide 4-103 Chapter 4 General VPN Setup Configuring Client Addressing The Add or Edit pane, General, Basic dialog box lets you specify a name for the tunnel group that you are adding, lets you select the group policy, and lets you configure password management. On the Edit Tunnel Group dialog box, the General dialog box displays the name and type of the selected tunnel group. All other functions are the same as for the Add Tunnel Group dialog box. Fields • Name—Specifies the name assigned to this tunnel group. For the Edit function, this field is display-only. • Type—Displays the type of tunnel group you are adding or editing. For Edit, this is a display-only field whose contents depend on your selection in the Add dialog box. • Group Policy—Lists the currently configured group policies. The default value is the default group policy, DfltGrpPolicy. • Strip the realm —Not available for Clientless SSL VPN. • Strip the group —Not available or Clientless SSL VPN. • Password Management—Lets you configure parameters relevant to overriding an account-disabled indication from a AAA server and to notifying users about password expiration. – Override account-disabled indication from AAA server—Overrides an account-disabled indication from a AAA server. Allowing override account-disabled is a potential security risk. Note – Enable notification upon password expiration to allow user to change password—Checking this check box makes the following two parameters available. If you do not also check the Enable notification prior to expiration check box, the user receives notification only after the password has expired. – Enable notification prior to expiration—When you check this option, the ASA notifies the remote user at login that the current password is about to expire or has expired, then offers the user the opportunity to change the password. If the current password has not yet expired, the user can still log in using that password. This parameter is valid for AAA servers that support such notification; that is, RADIUS, RADIUS with an NT server, and LDAP servers. The ASA ignores this command if RADIUS or LDAP authentication has not been configured. Note that this does not change the number of days before the password expires, but rather, it enables the notification. If you check this check box, you must also specify the number of days. – Notify...days prior to expiration—Specifies the number of days before the current password expires to notify the user of the pending expiration. The range is 1 through 180 days. Configuring Internal Group Policy IPsec Client Attributes Use this dialog box to specify whether to strip the realm and group from the username before passing them to the AAA server, and to specify password management options. Fields • Strip the realm from username before passing it on to the AAA server—Enables or disables stripping the realm (administrative domain) from the username before passing the username on to the AAA server. Check the Strip Realm check box to remove the realm qualifier of the username during authentication. You can append the realm name to the username for AAA: authorization, Cisco ASA Series VPN ASDM Configuration Guide 4-104 Chapter 4 General VPN Setup Configuring Client Addressing authentication and accounting. The only valid delimiter for a realm is the @ character. The format is username@realm, for example, JaneDoe@example.com. If you check this Strip Realm check box, authentication is based on the username alone. Otherwise, authentication is based on the full username@realm string. You must check this box if your server is unable to parse delimiters. Note You can append both the realm and the group to a username, in which case the ASA uses parameters configured for the group and for the realm for AAA functions. The format for this option is username[@realm]]<#or!>group], for example, JaneDoe@example.com#VPNGroup. If you choose this option, you must use either the # or ! character for the group delimiter because the ASA cannot interpret the @ as a group delimiter if it is also present as the realm delimiter. A Kerberos realm is a special case. The convention in naming a Kerberos realm is to capitalize the DNS domain name associated with the hosts in the Kerberos realm. For example, if users are in the example.com domain, you might call your Kerberos realm EXAMPLE.COM. The ASA does not include support for the user@grouppolicy, as the VPN 3000 Concentrator did. Only the L2TP/IPsec client supports the tunnel switching via user@tunnelgroup. • Strip the group from the username before passing it on to the AAA server—Enables or disables stripping the group name from the username before passing the username on to the AAA server. Check Strip Group to remove the group name from the username during authentication. This option is meaningful only when you have also checked the Enable Group Lookup box. When you append a group name to a username using a delimiter, and enable Group Lookup, the ASA interprets all characters to the left of the delimiter as the username, and those to the right as the group name. Valid group delimiters are the @, #, and ! characters, with the @ character as the default for Group Lookup. You append the group to the username in the format usernamegroup, the possibilities being, for example, JaneDoe@VPNGroup, JaneDoe#VPNGroup, and JaneDoe!VPNGroup. • Password Management—Lets you configure parameters relevant to overriding an account-disabled indication from a AAA server and to notifying users about password expiration. – Override account-disabled indication from AAA server—Overrides an account-disabled indication from a AAA server. Note Allowing override account-disabled is a potential security risk. – Enable notification upon password expiration to allow user to change password—Checking this check box makes the following two parameters available. You can select either to notify the user at login a specific number of days before the password expires or to notify the user only on the day that the password expires. The default is to notify the user 14 days prior to password expiration and every day thereafter until the user changes the password. The range is 1 through 180 days. Note This does not change the number of days before the password expires, but rather, it enables the notification. If you select this option, you must also specify the number of days. In either case, and, if the password expires without being changed, the ASA offers the user the opportunity to change the password. If the current password has not yet expired, the user can still log in using that password. Cisco ASA Series VPN ASDM Configuration Guide 4-105 Chapter 4 General VPN Setup Configuring Client Addressing This parameter is valid for AAA servers that support such notification; that is, RADIUS, RADIUS with an NT server, and LDAP servers. The ASA ignores this command if RADIUS or LDAP authentication has not been configured. Configuring Client Addressing for SSL VPN Connections Use this dialog box to specify the global client address assignment policy and to configure interface-specific address pools. You can also add, edit, or delete interface-specific address pools using this dialog box. The table at the bottom of the dialog box lists the configured interface-specific address pools. Fields • Interface-Specific IPv4 Address Pools—Lists the configured interface-specific address pools. • Interface-Specific IPv6 Address Pools—Lists the configured interface-specific address pools. • Add—Opens the Assign Address Pools to Interface dialog box, on which you can select an interface and select an address pool to assign. • Edit—Opens the Assign Address Pools to Interface dialog box with the interface and address pool fields filled in. • Delete—Deletes the selected interface-specific address pool. There is no confirmation or undo. Assign Address Pools to Interface Use this dialog box to select an interface and assign one or more address pools to that interface. Fields • Interface—Select the interface to which you want to assign an address pool. The default is DMZ. • Address Pools—Specify an address pool to assign to the specified interface. • Select—Opens the Select Address Pools dialog box, in which you can select one or more address pools to assign to this interface. Your selection appears in the Address Pools field of the Assign Address Pools to Interface dialog box. Select Address Pools The Select Address Pools dialog box shows the pool name, starting and ending addresses, and subnet mask of address pools available for client address assignment and lets you add, edit, or delete entries from that list. Fields • Add—Opens the Add IP Pool dialog box, on which you can configure a new IP address pool. • Edit—Opens the Edit IP Pool dialog box, on which you can modify a selected IP address pool. • Delete—Removes the selected address pool. There is no confirmation or undo. • Assign—Displays the address pool names that remained assigned to the interface. Double-click each unassigned pool you want to add to the interface. The Assign field updates the list of pool assignments. Cisco ASA Series VPN ASDM Configuration Guide 4-106 Chapter 4 General VPN Setup System Options Add or Edit an IP Address Pool Configures or modifies an IP address pool. Fields • Name—Specifies the name assigned to the IP address pool. • Starting IP Address—Specifies the first IP address in the pool. • Ending IP Address—Specifies the last IP address in the pool. • Subnet Mask—Selects the subnet mask to apply to the addresses in the pool. Authenticating SSL VPN Connections The SSL VPN Connections > Advanced > Authentication dialog box lets you configure authentication attributes for SSL VPN connections. System Options This panel can be reached by navigating these paths: • Configuration > Site-to-Site VPN > Advanced > System Options • Configuration > Remote Access VPN > Network (Client) Access > Advanced > IPsec > System Options The System Options pane lets you configure features specific to VPN sessions on the ASA. Fields • Limit the maximum number of active IPsec VPN sessions—Enables or disables limiting the maximum number of active IPsec VPN sessions. The range depends on the hardware platform and the software license. – Maximum IPsec Sessions—Specifies the maximum number of active IPsec VPN sessions allowed. This field is active only when you select the preceding check box to limit the maximum number of active IPsec VPN sessions. • L2TP Tunnel Keep-alive Timeout—Specifies the frequency, in seconds, of keepalive messages. The range is 10 through 300 seconds. The default is 60 seconds. This is an advanced system option for Network (Client) Access only. • Reclassify existing flows when VPN tunnels establish • Preserve stateful VPN flows when the tunnel drops—Enables or disables preserving IPsec tunneled flows in Network-Extension Mode (NEM). With the persistent IPsec tunneled flows feature enabled, as long as the tunnel is recreated within the timeout dialog box, data continues flowing successfully because the security appliance still has access to the state information. This option is disabled by default. Note Tunneled TCP flows are not dropped, so they rely on the TCP timeout for cleanup. However, if the timeout is disabled for a particular tunneled flow, that flow remains in the system until being cleared manually or by other means (for example, by a TCP RST from the peer). Cisco ASA Series VPN ASDM Configuration Guide 4-107 Chapter 4 General VPN Setup Zone Labs Integrity Server • IPsec Security Association Lifetime—Configures the duration of a Security Association (SA). This parameter specifies how to measure the lifetime of the IPsec SA keys, which is how long the IPsec SA lasts until it expires and must be renegotiated with new keys. – Time—Specifies the SA lifetime in terms of hours (hh), minutes (mm) and seconds (ss). – Traffic Volume—Defines the SA lifetime in terms of kilobytes of traffic. Enter the number of kilobytes of payload data after which the IPsec SA expires, or check unlimited. Minimum is 100 KB, default is 10000 KB, maximum is 2147483647 KB. • Enable PMTU (Path Maximum Transmission Unit) Aging—Allows an administrator to enable PMTU aging. – Interval to Reset PMTU of an SA (Security Association)—Enter the number of seconds at which the PMTU value is reset to its original value. Zone Labs Integrity Server Configuration > Remote Access VPN > Network (Client) Access > Advanced > IPsec > Zone Labs Integrity Server The Zone Labs Integrity Server panel lets you configure the ASA to support a Zone Labs Integrity Server. This server is part of the Integrity System, a system designed to enforce security policies on remote clients entering the private network. In essence, the ASA acts as a proxy for the client PC to the Firewall Server and relays all necessary Integrity information between the Integrity client and the Integrity server. Cisco ASA Series VPN ASDM Configuration Guide 4-108 Chapter 4 General VPN Setup Easy VPN Remote Note The current release of the security appliance supports one Integrity Server at a time even though the user interfaces support the configuration of up to five Integrity Servers. If the active Server fails, configure another Integrity Server on the ASA and then reestablish the client VPN session. Fields • Server IP address—Type the IP address of the Integrity Server. Use dotted decimal notation. • Add—Adds a new server IP address to the list of Integrity Servers. This button is active when an address is entered in the Server IP address field. • Delete—Deletes the selected server from the list of Integrity Servers. • Move Up—Moves the selected server up in the list of Integrity Servers. This button is available only when there is more than one server in the list. • Move Down—Moves the selected server down in the list of Integrity Servers. This button is available only when there is more than one server in the list. • Server Port—Type the ASA port number on which it listens to the active Integrity server. This field is available only if there is at least one server in the list of Integrity Servers. The default port number is 5054, and it can range from 10 to 10000. This field is only available when there is a server in the Integrity Server list. • Interface—Choose the interface ASA interface on which it communicates with the active Integrity Server. This interface name menu is only available when there is a server in the Integrity Server list. • Fail Timeout—Type the number of seconds that the ASA should wait before it declares the active Integrity Server to be unreachable. The default is 10 and the range is from 5 to 20. • SSL Certificate Port: Specify the ASA port to be used for SSL Authorization. The default is port 80. • Enable SSL Authentication—Check to enable authentication of the remote client SSL certificate by the ASA. By default, client SSL authentication is disabled. • Close connection on timeout—Check to close the connection between the ASA and the Integrity Server on a timeout. By default, the connection remains open. • Apply—Click to apply the Integrity Server setting to the ASA running configuration. • Reset—Click to remove Integrity Server configuration changes that have not yet been applied. Easy VPN Remote Configuration > VPN > Easy VPN Remote Easy VPN Remote lets the ASA 5505 act as an Easy VPN client device. The ASA 5505 can then initiate a VPN tunnel to an Easy VPN server, which can be an ASA, a Cisco VPN 3000 Concentrator, a Cisco IOS-based router, or a firewall acting as an Easy VPN server. The Easy VPN client supports one of two modes of operation: Client Mode or Network Extension Mode (NEM). The mode of operation determines whether the Easy VPN Client inside hosts are accessible from the Enterprise network over the tunnel. Specifying a mode of operation is mandatory before making a connection because Easy VPN Client does not have a default mode. Client mode, also called Port Address Translation (PAT) mode, isolates all devices on the Easy VPN Client private network from those on the enterprise network. The Easy VPN Client performs Port Address Translation (PAT) for all VPN traffic for its inside hosts. IP address management is neither required for the Easy VPN Client inside interface or the inside hosts. Cisco ASA Series VPN ASDM Configuration Guide 4-109 Chapter 4 General VPN Setup Easy VPN Remote NEM makes the inside interface and all inside hosts routable across the enterprise network over the tunnel. Hosts on the inside network obtain their IP addresses from an accessible subnet (statically or via DHCP) pre-configured with static IP addresses. PAT does not apply to VPN traffic in NEM. This mode does not require a VPN configuration for each client. The Cisco ASA 5505 configured for NEM mode supports automatic tunnel initiation. The configuration must store the group name, user name, and password. Automatic tunnel initiation is disabled if secure unit authentication is enabled. The network and addresses on the private side of the Easy VPN Client are hidden, and cannot be accessed directly. Fields • Enable Easy VPN Remote—Enables the Easy VPN Remote feature and makes available the rest of the fields on this dialog box for configuration. • Mode—Selects either Client mode or Network extension mode. – Client mode—Uses Port Address Translation (PAT) mode to isolate the addresses of the inside hosts, relative to the client, from the enterprise network. – Network extension mode—Makes those addresses accessible from the enterprise network. Note If the Easy VPN Remote is using NEM and has connections to secondary servers, establish an ASDM connection to each headend and check Enable Reverse Route Injection on the Configuration > VPN > IPsec > IPsec Rules > Tunnel Policy (Crypto Map) - Advanced dialog box to configure dynamic announcements of the remote network using RRI. – Auto connect—The Easy VPN Remote establishes automatic IPsec data tunnels unless both of the following are true: Network extension mode is configured locally, and split-tunneling is configured on the group policy pushed to the Easy VPN Remote. If both are true, checking this attribute automates the establishment of IPsec data tunnels. Otherwise, this attribute has no effect. • Group Settings—Specifies whether to use a pre-shared key or an X.509 certificate for user authentication. – Pre-shared key—Enables the use of a pre-shared key for authentication and makes available the subsequent Group Name, Group Password, and Confirm Password fields for specifying the group policy name and password containing that key. – Group Name—Specifies the name of the group policy to use for authentication. – Group Password—Specifies the password to use with the specified group policy. – Confirm Password—Requires you to confirm the group password just entered. – X.509 Certificate—Specifies the use of an X.509 digital certificate, supplied by a Certificate Authority, for authentication. – Select Trustpoint—Lets you select a trustpoint, which can be an IP address or a hostname, from the drop-down list. To define a trustpoint, click the link to Trustpoint(s) configuration at the bottom of this area. – Send certificate chain—Enables sending a certificate chain, not just the certificate itself. This action includes the root certificate and any subordinate CA certificates in the transmission. • User Settings—Configures user login information. Cisco ASA Series VPN ASDM Configuration Guide 4-110 Chapter 4 General VPN Setup Advanced Easy VPN Properties – User Name—Configures the VPN username for the Easy VPN Remote connection. Xauth provides the capability of authenticating a user within IKE using TACACS+ or RADIUS. Xauth authenticates a user (in this case, the Easy VPN hardware client) using RADIUS or any of the other supported user authentication protocols. The Xauth username and password parameters are used when secure unit authentication is disabled and the server requests Xauth credentials. If secure unit authentication is enabled, these parameters are ignored, and the ASA prompts the user for a username and password. – User Password—Configures the VPN user password for the Easy VPN Remote connection. – Confirm Password—Requires you to confirm the user password just entered. • Easy VPN Server To Be Added—Adds or removes an Easy VPN server. Any ASA or VPN 3000 Concentrator Series can act as a Easy VPN server. A server must be configured before a connection can be established. The ASA supports IPv4 addresses, the names database, or DNS names and resolves addresses in that order. The first server in the Easy VPN Server(s) list is the primary server. You can specify a maximum of ten backup servers in addition to the primary server. – Name or IP Address—The name or IP address of an Easy VPN server to add to the list. – Add—Moves the specified server to the Easy VPN Server(s) list. – Remove—Moves the selected server from the Easy VPN Server(s) list to the Name or IP Address file. Once you do this, however, you cannot re-add the same address unless you re-enter the address in the Name or IP Address field. – Easy VPN Server(s)—Lists the configured Easy VPN servers in priority order. – Move Up/Move Down—Changes the position of a server in the Easy VPN Server(s) list. These buttons are available only when there is more than one server in the list. Advanced Easy VPN Properties Configuration > VPN > Easy VPN Remote > Advanced Device Pass-Through Certain devices like Cisco IP phones, printers, and the like are incapable of performing authentication, and therefore of participating in individual unit authentication. To accommodate these devices, the device pass-through feature, enabled by the MAC Exemption attributes, exempts devices with the specified MAC addresses from authentication when Individual User Authentication is enabled. The first 24 bits of the MAC address indicate the manufacturer of the piece of equipment. The last 24 bits are the unit’s serial number in hexadecimal format. Tunneled Management When operating an ASA model 5505 device behind a NAT device, use the Tunneled Management attributes to specify how to configure device management— in the clear or through the tunnel—and specify the network or networks allowed to manage the Easy VPN Remote connection through the tunnel. The public address of the ASA 5505 is not accessible when behind the NAT device unless you add static NAT mappings on the NAT device. When operating a Cisco ASA 5505 behind a NAT device, use the vpnclient management command to specify how to configure device management— with additional encryption or without it—and specify the hosts or networks to be granted administrative access. The public address of the ASA 5505 is not accessible when behind the NAT device unless you add static NAT mappings on the NAT device. Cisco ASA Series VPN ASDM Configuration Guide 4-111 Chapter 4 General VPN Setup Advanced Easy VPN Properties Fields • MAC Exemption—Configures a set of MAC addresses and masks used for device pass-through for the Easy VPN Remote connection – MAC Address—Exempts the device with the specified MAC address from authentication. The format for specifying the MAC address this field uses three hex digits, separated by periods; for example, 45ab.ff36.9999. – MAC Mask—The format for specifying the MAC mask in this field uses three hex digits, separated by periods; for example, the MAC mask ffff.ffff.ffff matches just the specified MAC address. A MAC mask of all zeroes matches no MAC address, and a MAC mask of ffff.ff00.0000 matches all devices made by the same manufacturer. – Add—Adds the specified MAC address and mask pair to the MAC Address/Mask list. – Remove—Moves the selected MAC address and mask pair from the MAC Address/MAC list to the individual MAC Address and MAC Mask fields. • Tunneled Management—Configures IPsec encryption for device management and specifies the network or networks allowed to manage the Easy VPN hardware client connection through the tunnel. Selecting Clear Tunneled Management merely removes that IPsec encryption level and does not affect any other encryption, such as SSH or https, that exists on the connection. – Enable Tunneled Management—Adds a layer of IPsec encryption to the SSH or HTTPS encryption already present in the management tunnel. – Clear Tunneled Management—Uses the encryption already present in the management tunnel, without additional encryption. – IP Address— Specifies the IP address of the host or network to which you want to grant administrative access to the Easy VPN hardware client through the VPN tunnel. You can individually add one or more IP addresses and their respective network masks. – Mask—Specifies the network mask for the corresponding IP address. – Add—Moves the specified IP address and mask to the IP Address/Mask list. – Remove—Moves the selected IP address and mask pair from the IP Address/Mask list to the individual IP Address and Mask fields in this area. – IP Address/Mask—Lists the configured IP address and mask pairs to be operated on by the Enable or Clear functions in this area. • IPsec Over TCP—Configure the Easy VPN Remote connection to use TCP-encapsulated IPsec. – Enable—Enables IPsec over TCP. Note Choose Configuration > VPN > IPsec > Pre-Fragmentation, double-click the outside interface, and set the DF Bit Setting Policy to Clear if you configure the Easy VPN Remote connection to use TCP-encapsulated IPsec. The Clear setting lets the ASA send large packets. – Enter Port Number—Specifies the port number to use for the IPsec over TCP connection. • Server Certificate—Configures the Easy VPN Remote connection to accept only connections to Easy VPN servers with the specific certificates specified by the certificate map. Use this parameter to enable Easy VPN server certificate filtering. To define a certificate map, go to Configuration > VPN > IKE > Certificate Group Matching > Rules. Cisco ASA Series VPN ASDM Configuration Guide 4-112 Chapter 4 General VPN Setup AnyConnect Essentials AnyConnect Custom Attributes Custom attributes are added here to support special features that are not defined in the ASDM. Deferred upgrade is the feature in AnyConnect 3.1 that uses custom attributes. See Configuring AnyConnect Client Custom Attributes for an Internal Group Policy, page 4-23 AnyConnect Essentials AnyConnect Essentials is a separately licensed SSL VPN client, entirely configured on the ASA, that provides the full AnyConnect capability, with the following exceptions: • No CSD (including HostScan/Vault/Cache Cleaner) • No clientless SSL VPN • Optional Windows Mobile Support (requires AnyConnect for Windows Mobile license) The AnyConnect Essentials client provides remote end users running Microsoft Windows Vista, Windows Mobile, Windows XP or Windows 2000, Linux, or Macintosh OS X, with the benefits of a Cisco SSL VPN client. To enable AnyConnect Essentials, check the Enable AnyConnect Essentials check box on the AnyConnect Essentials pane, which appears only if the AnyConnect Essentials license is installed on the ASA. When AnyConnect Essentials is enabled, AnyConnect clients use Essentials mode, and clientless SSL VPN access is disabled. When AnyConnect Essentials is disabled, AnyConnect clients use the full AnyConnect SSL VPN Client. Note The status information about the AnyConnect Essentials license on the Configuration > Device Management > Licensing > Activation Key pane simply reflects whether the AnyConnect Essentials license is installed. This status is not affected by the setting of the Enable AnyConnect Essentials License check box. AnyConnect Essentials mode cannot be enabled when active clientless sessions exist to the device. To view SSL VPN session details click the Monitoring > VPN > VPN Sessions link in the SSL VPN Sessions section. This opens the Monitoring > VPN > VPN > VPN Statistics > Sessions pane. To see session details, choose Filter By: Clientless SSL VPN and click Filter. This displays session details. To see how many clientless SSL VPN sessions are currently active, without showing session details, click Check Number of Clientless SSL Sessions. If the SSL VPN session count is zero, you can enable AnyConnect Essentials. Note Secure Desktop does not work when AnyConnect Essentials is enabled. You can, however, disable AnyConnect Essentials when you enable Secure Desktop. DTLS Settings Enabling Datagram Transport Layer Security (DTLS) allows the AnyConnect VPN client establishing an SSL VPN connection to use two simultaneous tunnels—an SSL tunnel and a DTLS tunnel. Using DTLS avoids latency and bandwidth problems associated with some SSL connections and improves the performance of real-time applications that are sensitive to packet delays. Cisco ASA Series VPN ASDM Configuration Guide 4-113 Chapter 4 General VPN Setup AnyConnect VPN Client Images If you do not enable DTLS, AnyConnect client users establishing SSL VPN connections connect with an SSL VPN tunnel only. Fields • Interface—Displays a list of interfaces on the ASA. • DTLS Enabled—Click to enable DTLS connections with the AnyConnect client on the interfaces. • UDP Port (default 443)—(Optional) Specify a separate UDP port for DTLS connections. AnyConnect VPN Client Images This pane lists the AnyConnect client images that are configured in ASDM. Fields • AnyConnect Client Images table—Displays the package files configured in ASDM, and allows you to establish the order that the ASA downloads the images to the remote PC. – Add—Displays the Add AnyConnect Client Image dialog box, where you can specify a file in flash memory as a client image file, or you can browse flash memory for a file to specify as a client image. You can also upload a file from a local computer to the flash memory. – Replace—Displays the Replace AnyConnect Client Image dialog box, where you can specify a file in flash memory as an client image to replace an image highlighted in the SSL VPN Client Images table. You can also upload a file from a local computer to the flash memory. – Delete—Deletes an image from the table. This does not delete the package file from flash. – Move Up and Move Down—The up and down arrows change the order in which the ASA downloads the client images to the remote PC. It downloads the image at the top of the table first. Therefore, you should move the image used by the most commonly-encountered operating system to the top. Add/Replace AnyConnect VPN Client Image In this pane, you can specify a filename for a file on the ASA flash memory that you want to add as an AnyConnect client image, or to replace an image already listed in the table. You can also browse the flash memory for a file to identify, or you can upload a file from a local computer. Fields • Flash SVC Image—Specify the file in flash memory that you want to identify as an SSL VPN client image. • Browse Flash—Displays the Browse Flash dialog box where you can view all the files on flash memory. • Upload—Displays the Upload Image dialog box where you can upload a file from a local PC that you want to identify as an client image. • Regular expression to match user-agent—Specifies a string that the ASA uses to match against the User-Agent string passed by the browser. For mobile users, you can decrease the connection time of the mobile device by using the feature. When the browser connects to the ASA, it includes the User-Agent string in the HTTP header. When the ASA receives the string, if the string matches an expression configured for an image, it immediately downloads that image without testing the other Cisco ASA Series VPN ASDM Configuration Guide 4-114 Chapter 4 General VPN Setup Bypass Interface ACL client images. Upload Image In this pane, you can specify the path of a file on the local computer or in flash memory of the security appliance that you want to identify as an AnyConnect client image. You can also browse the local computer or the flash memory of the security appliance for a file to identify. Fields • Local File Path—Identifies the filename of the file in on the local computer that you want to identify as an SSL VPN client image. • Browse Local Files—Displays the Select File Path dialog box where you can view all the files on local computer and where you can select a file to identify as a client image. • Flash File System Path—Identifies the filename of the file in the flash memory of the security appliance that you want to identify as an SSL VPN client image. • Browse Flash—Displays the Browse Flash Dialog dialog box where you can view all the files on flash memory of the security appliance and where you can choose a file to identify as a client image. • Upload File—Initiates the file upload. Bypass Interface ACL You can require an access rule to apply to the local IP addresses by unchecking this check box. The access rule applies to the local IP address, and not to the original client IP address used before the VPN packet was decrypted. • Enable inbound IPsec sessions to bypass interface access-lists. Group policy and per-user authorization ACLs still apply to the traffic—By default, the ASA allows VPN traffic to terminate on an ASA interface; you do not need to allow IKE or ESP (or other types of VPN packets) in an access rule. When this check box is checked, you also do not need an access rule for local IP addresses of decrypted VPN packets. Because the VPN tunnel was terminated successfully using VPN security mechanisms, this feature simplifies configuration and maximizes the ASA performance without any security risks. (Group policy and per-user authorization ACLs still apply to the traffic.) Configuring AnyConnect Host Scan Configuration > Remote Access VPN > Host Scan Image The AnyConnect Posture Module provides the AnyConnect Secure Mobility Client the ability to identify the operating system, anti-virus, anti-spyware, and firewall software installed on the host. The Host Scan application gathers this information. Using the secure desktop manager tool in the Adaptive Security Device Manager (ASDM), you can create a prelogin policy which evaluates the operating system, anti-virus, anti-spyware, and firewall software Host Scan identifies. Based on the result of the prelogin policy’s evaluation, you can control which hosts are allowed to create a remote access connection to the security appliance. Cisco ASA Series VPN ASDM Configuration Guide 4-115 Chapter 4 General VPN Setup Configuring AnyConnect Host Scan The Host Scan support chart contains the product name and version information for the anti-virus, anti-spyware, and firewall applications you use in your prelogin policies. We deliver Host Scan and the Host Scan support chart, as well as other components, in the Host Scan package. Starting with AnyConnect Secure Mobility Client, release 3.0, Host Scan is available separately from CSD. This means you can deploy Host Scan functionality without having to install CSD and you will be able to update your Host Scan support charts by upgrading the latest Host Scan package. Posture assessment and the AnyConnect telemetry module require Host Scan to be installed on the host. This chapter contains the following sections: • Host Scan Dependencies and System Requirements, page 4-116 • Host Scan Packaging, page 4-117 • Installing and Enabling Host Scan on the ASA, page 4-117 • Other Important Documentation Addressing Host Scan, page 4-121 Host Scan Dependencies and System Requirements Dependencies The AnyConnect Secure Mobility Client with the posture module requires these minimum ASA components: • ASA 8.4 • ASDM 6.4 These AnyConnect features require that you install the posture module. • SCEP authentication • AnyConnect Telemetry Module System Requirements The posture module can be installed on any of these platforms: • Windows XP (x86 and x86 running on x64) • Windows Vista (x86 and x86 running on x64) • Windows 7 (x86 and x86 running on x64) • Mac OS X 10.5,10.6 (32-bit and 32-bit running on 64-bit) • Linux (32-bit and 32-bit running on 64-bit) • Windows Mobile Licensing These are the AnyConnect licensing requirements for the posture module: • AnyConnect Premium for basic Host Scan. • Advanced Endpoint Assessment license is required for – Remediation Cisco ASA Series VPN ASDM Configuration Guide 4-116 Chapter 4 General VPN Setup Configuring AnyConnect Host Scan – Mobile Device Management Entering an Activation Key to Support Advanced Endpoint Assessment Advanced Endpoint Assessment includes all of the Endpoint Assessment features and lets you configure an attempt to update noncompliant computers to meet version requirements. You can use ASDM to activate a key to support Advanced Endpoint Assessment after acquiring it from Cisco, as follows: Step 1 Choose Configuration > Device Management > Licensing > Activation Key. Step 2 Enter the key in the New Activation Key field. Step 3 Click Update Activation Key. Step 4 Choose File > Save Running Configuration to Flash. An Advanced Endpoint Assessment entry appears and the Configure button becomes active in the Host Scan Extensions area of the Configuration > Remote Access VPN > Secure Desktop Manager > Host Scan pane, which is accessible only if CSD is enabled. Host Scan Packaging You can load the Host Scan package on to the ASA in one of these ways: • You can upload it as a standalone package: hostscan-version.pkg • You can upload it by uploading an AnyConnect Secure Mobility package: anyconnect-NGC-win-version-k9.pkg • You can upload it by uploading a Cisco Secure Desktop package: csd_version-k9.pkg File Description hostscan-version.pkg This file contains the Host Scan software as well as the Host Scan library and support charts. anyconnect-NGC-win-version-k9.pkg This package contains all the Cisco AnyConnect Secure Mobility Client features including the hostscan-version.pkg file. csd_version-k9.pkg This file contains all Cisco Secure Desktop features including Host Scan software as well as the Host Scan library and support charts. This method requires a separate license for Cisco Secure Desktop. Installing and Enabling Host Scan on the ASA These tasks describe installing and enabling Host Scan on the ASA: • Installing or Upgrading Host Scan • Enabling or Disabling Host Scan Cisco ASA Series VPN ASDM Configuration Guide 4-117 Chapter 4 General VPN Setup Configuring AnyConnect Host Scan • Enabling or Disabling CSD on the ASA • Viewing the Host Scan Version Enabled on the ASA • Uninstalling Host Scan • Uninstalling CSD from the ASA • Assigning AnyConnect Posture Module to a Group Policy Installing or Upgrading Host Scan Use this procedure to upload, or upgrade, and enable a new Host Scan image on the ASA. This image can enable the host scan functionality for AnyConnect, or you can use it to upgrade the host scan support chart for an existing deployment of Cisco Secure Desktop (CSD). You can specify a standalone Host Scan package or an AnyConnect Secure Mobility Client version 3.0 or later package in the field. If you previously uploaded a CSD image to the ASA, the Host Scan image you specify will upgrade or downgrade the existing Host Scan files that were delivered with that CSD package. You do not need to restart the security appliance after you install or upgrade Host Scan; however, you must exit and restart Adaptive Security Device Manager (ASDM) to access Secure Desktop Manager. Note Host scan requires an AnyConnect Secure Mobility Client premium license. Step 1 Use your Internet browser to download the hostscan_version-k9.pkg file or anyconnect-NGC-win-version-k9.pkg file to your computer. You cannot use a csd_version-k9.pkg with this procedure. Step 2 Open ASDM and choose Configuration > Remote Access VPN > Host Scan Image. ASDM opens the Host Scan Image panel (Figure 4-7). Figure 4-7 Host Scan Image Panel Step 3 Click Upload to prepare to transfer a copy of the Host Scan package from your computer to a drive on the ASA. Step 4 In the Upload Image dialog box, click Browse Local Files to search for the Host Scan package on your local computer. Cisco ASA Series VPN ASDM Configuration Guide 4-118 Chapter 4 General VPN Setup Configuring AnyConnect Host Scan Step 5 Select the hostscan_version.pkg file or anyconnect-NGC-win-version-k9.pkg file you downloaded in Step 1 and click Select. The path to the file you selected is in the Local File Path field and the Flash File System Path field reflects the destination path of the Host Scan package. If your ASA has more than one flash drive, you can edit the Flash File System Path to indicate another flash drive. Step 6 Click Upload File. ASDM transfers a copy of the file to the flash card. An Information dialog box displays the following message: File has been uploaded to flash successfully. Step 7 Click OK. Step 8 In the Use Uploaded Image dialog, click OK to use the Host Scan package file you just uploaded as the current image. Step 9 Check Enable Host Scan/CSD if it is not already checked. Step 10 Click Apply. Note Step 11 If AnyConnect Essentials is enabled on the ASA, you receive a message that CSD will not work with it. You have the choice to Disable or Keep AnyConnect Essentials. From the File menu, select Save Running Configuration To Flash. Enabling or Disabling Host Scan When you first install or upgrade a Host Scan image using ASDM, you enable the image as part of that procedure. See “Installing and Enabling Host Scan on the ASA” section on page 4-117. Otherwise, to enable or disable a Host Scan image using ASDM, follow this procedure: Step 1 Open ASDM and choose Configuration > Remote Access VPN > Host Scan Image. ASDM opens the Host Scan Image panel (Figure 4-7). Step 2 Check Enable Host Scan/CSD to enable Host Scan or uncheck Enable Host Scan/CSD to disable Host Scan. Step 3 Click Apply. Enabling or Disabling CSD on the ASA Enabling CSD loads the CSD configuration file, data.xml, from the flash device to the running configuration. Disabling CSD does not alter the CSD configuration. Use ASDM to enable or disable CSD as follows: Step 1 Choose Configuration > Clientless SSL VPN > Secure Desktop > Setup. ASDM opens the Setup pane (Figure 4-7). Cisco ASA Series VPN ASDM Configuration Guide 4-119 Chapter 4 General VPN Setup Configuring AnyConnect Host Scan Note Step 2 The Secure Desktop Image field displays the image (and version) that is currently installed. The Enable Secure Desktop check box indicates whether CSD is enabled. Check or uncheck Enable Secure Desktop and click Apply. ASDM enables or disables CSD. Step 3 Click the X in the upper right corner of the ASDM window to exit. A window displays the following message: The configuration has been modified. Do you want to save the running configuration to flash memory? Step 4 Click Save. ASDM saves the configuration and closes. Viewing the Host Scan Version Enabled on the ASA Open ASDM and select Configuration > Remote Access VPN > Host Scan Image. If there is a Host Scan image designated in the Host Scan Image location field, and the Enable HostScan/CSD box is checked, the version of that image is the Host Scan version being used by the ASA. If the Host Scan Image filed is empty, and the Enable HostScan/CSD box is checked, select Configuration > Remote Access VPN > Secure Desktop Manager. The version of CSD in the Secure Desktop Image Location field is the Host Scan version being used by the ASA. Uninstalling Host Scan Uninstalling Host Scan package removes it from view on the ASDM interface and prevents the ASA from deploying it even if Host Scan or CSD is enabled. Uninstalling Host Scan does not delete the Host Scan package from the flash drive. Uninstall Host Scan on the security appliance as follows: Step 1 Open ASDM and select Configuration > Remote Access VPN > Host Scan Image. Step 2 In the Host Scan Image pane, click Uninstall. ASDM removes the text from the Location text box. Step 3 From the File menu select Save Running Configuration to Flash. Uninstalling CSD from the ASA Uninstalling CSD removes the CSD configuration file, data.xml, from the desktop directory on the flash card. If you want to retain the file, copy it using an alternative name or download it to your workstation before you uninstall CSD. Uninstall CSD on the security appliance as follows: Step 1 Open ASDM and choose Configuration > Remote Access VPN > Secure Desktop Manager > Setup. ASDM opens the Setup pane (Figure 4-7). Cisco ASA Series VPN ASDM Configuration Guide 4-120 Chapter 4 General VPN Setup Configuring AnyConnect Host Scan Step 2 Click Uninstall. A confirmation window displays the following message: Do you want to delete disk0:/csd_..*.pkg and all CSD data files? Step 3 Click Yes. ASDM removes the text from the Location text box and removes the Secure Desktop Manager menu options below Setup. Step 4 Click the X in the upper right corner of the ASDM window to exit. A window displays the following message: The configuration has been modified. Do you want to save the running configuration to flash memory? Step 5 Click Save. ASDM saves the configuration and closes. Assigning AnyConnect Posture Module to a Group Policy Step 1 Open ASDM and choose Configuration > Remote Access VPN > Network (Client) Access > Group Policies. Step 2 In the Group Policies panel, click Add to create a new group policy or select the group policy to which you want to assign the Host Scan package and click Edit. Step 3 In the Edit Internal Group Policy panel, expand the Advanced navigation tree on the left side of the panel and select AnyConnect Client. Step 4 Uncheck the Optional Client Modules to Download Inherit checkbox. Step 5 In the Optional Client Modules to Download drop down menu, check the AnyConnect Posture Module and click OK. Step 6 Click OK. Other Important Documentation Addressing Host Scan Once Host Scan gathers the posture credentials from the endpoint computer, you will need to understand subjects like, configuring prelogin policies, configuring dynamic access policies, and using Lua expressions to make use of the information. These topics are covered in detail in these documents: • Cisco Secure Desktop Configuration Guides • Cisco Adaptive Security Device Manager Configuration Guides See also the Cisco AnyConnect Secure Mobility Client Administrator Guide, Release 3.0 for more information about how Host Scan works with AnyConnect clients. Cisco ASA Series VPN ASDM Configuration Guide 4-121 Chapter 4 General VPN Setup Configuring Maximum VPN Sessions Configuring Maximum VPN Sessions To specify the maximum allowed number of VPN sessions or AnyConnect client VPN sessions, perform the following steps: Step 1 Choose Configuration > Remote Access VPN > Advanced > Maximum VPN Sessions. Step 2 In the Maximum AnyConnect Sessions field, enter the maximum number of sessions allowed. Valid values range from 1 to the maximum number of sessions that are allowed by your license. Step 3 In the Maximum Other VPN Sessions field, enter the maximum number of VPN sessions allowed, which includes Cisco VPN client (IPsec IKEv1) LAN-to-LAN VPN, and clientless SSL VPN sessions. Valid values range from 1 to the maximum number of sessions that are allowed by your license. Step 4 Click Apply. Configuring the Pool of Cryptographic Cores You can change the allocation of cryptographic cores on Symmetric Multi-Processing (SMP) platforms to give you better throughput performance for AnyConnect TLS/DTLS traffic. These changes can accelerate the SSL VPN datapath and provide customer-visible performance gains in AnyConnect, smart tunnels, and port forwarding. To configure the pool of cryptographic cores, perform the following steps. Limitations • Cryptographic core rebalancing is available on the following platforms: – 5585-X – 5580 – 5545-X – 5555-X – ASASM • The large modulus operation is only available for 5510, 5520, 5540, and 5550 platforms. Detailed Steps Step 1 Choose Configuration > Remote Access VPN > Advanced > Crypto Engine. Step 2 Check Enable Large Modulus Acceleration if you want to perform large modulus operations in the hardware. Step 3 From the Accelerator Bias drop-down menu, choose one of the following: Note • This field only shows up if the feature is available in ASA. balanced—Equally distributes cryptography hardware resources (Admin/SSL and IPsec cores). Cisco ASA Series VPN ASDM Configuration Guide 4-122 Chapter 4 General VPN Setup Configuring the Pool of Cryptographic Cores Step 4 • ipsec—Allocates cryptography hardware resources to favor IPsec (includes SRTP encrypted voice traffic). • ssl—Allocates cryptography hardware resources to favor Admin/SSL. Click Apply. Cisco ASA Series VPN ASDM Configuration Guide 4-123 Chapter 4 Configuring the Pool of Cryptographic Cores Cisco ASA Series VPN ASDM Configuration Guide 4-124 General VPN Setup CH AP TE R 5 Configuring IP Addresses for VPNs This chapter describes IP address assignment methods. IP addresses make internetwork connections possible. They are like telephone numbers: both the sender and receiver must have an assigned number to connect. But with VPNs, there are actually two sets of addresses: the first set connects client and server on the public network. Once that connection is made, the second set connects client and server through the VPN tunnel. In ASA address management, we are dealing with the second set of IP addresses: those private IP addresses that connect a client with a resource on the private network, through the tunnel, and let the client function as if it were directly connected to the private network. Furthermore, we are dealing only with the private IP addresses that get assigned to clients. The IP addresses assigned to other resources on your private network are part of your network administration responsibilities, not part of VPN management. Therefore, when we discuss IP addresses here, we mean those IP addresses available in your private network addressing scheme that let the client function as a tunnel endpoint. This chapter includes the following sections: • Configuring an IP Address Assignment Policy, page 5-1 • Configuring Local IP Address Pools, page 5-3 • Configuring DHCP Addressing, page 5-5 • Configuring DHCP Addressing, page 5-5 Configuring an IP Address Assignment Policy The ASA can use one or more of the following methods for assigning IP addresses to remote access clients. If you configure more than one address assignment method, the ASA searches each of the options until it finds an IP address. By default, all methods are enabled. • Use authentication server — Retrieves addresses from an external authentication, authorization, and accounting server on a per-user basis. If you are using an authentication server that has IP addresses configured, we recommend using this method. You can configure AAA servers in the Configuration > AAA Setup pane.This method is available for IPv4 and IPv6 assignment policies. • Use DHCP — Obtains IP addresses from a DHCP server. If you want to use DHCP, you must configure a DHCP server. You must also define the range of IP addresses that the DHCP server can use. If you use DHCP, configure the server in the Configuration > Remote Access VPN > DHCP Server pane. This method is available for IPv4 assignment policies. Cisco ASA Series VPN ASDM Configuration Guide 5-1 Chapter 5 Configuring IP Addresses for VPNs Configuring an IP Address Assignment Policy • Use an internal address pool — Internally configured address pools are the easiest method of address pool assignment to configure. If you use this method, configure the IP address pools in Configuration > Remote Access VPN > Network (Client) Access > Address Assignment > Address Pools pane. This method is available for IPv4 and IPv6 assignment policies. – Allow the reuse of an IP address so many minutes after it is released—Delays the reuse of an IP address after its return to the address pool. Adding a delay helps to prevent problems firewalls can experience when an IP address is reassigned quickly. By default, this is unchecked, meaning the ASA does not impose a delay. If you want one, check the box and enter the number of minutes in the range 1 - 480 to delay IP address reassignment.This configurable element is available for IPv4 assignment policies. Use one of these methods to specify a way to assign IP addresses to remote access clients. • Configuring IP Address Assignment Options using ASDM Configuring IP Address Assignment Options using ASDM Step 1 Select Configuration > Remote Access VPN > Network (Client) Access > Address Assignment > Assignment Policy Step 2 In the IPv4 Policy area, check the address assignment method to enabled it or uncheck the address assignment method to disable it. These methods are enabled by default: • Use Authentication server. Enables the use of a Authentication Authorization and Accounting (AAA) server you have configured to provide IP addresses. • Use DHCP. Enables the use of a Dynamic Host Configuration Protocol (DHCP) server you have configured to provide IP addresses. • Use internal address pools: Enables the use of a local address pool configured on the ASA. If you enable Use internal address pools, you can also enable the reuse of an IPv4 address after it has been released. You can specify a range of minutes from 0-480 after which the IP v4 address can be reused. Step 3 In the IPv6 Policy area, check the address assignment method to enable it or uncheck the address assignment method to disable it. These methods are enabled by default: • Use Authentication server. Enables the use of a Authentication Authorization and Accounting (AAA) server you have configured to provide IP addresses. • Use internal address pools: Enables the use of a local address pool configured on the ASA. Step 4 Click Apply. Step 5 Click OK. Modes The following table shows the modes in which this feature is available: Cisco ASA Series VPN ASDM Configuration Guide 5-2 Chapter 5 Configuring IP Addresses for VPNs Configuring Local IP Address Pools Firewall Mode Security Context Multiple Routed • Transparent Single Context System — — — • Viewing Address Assignment Methods Use one of these methods to view the address assignment method configured on the ASA: Viewing IPv4 and IPv6 Address Assignments using ASDM Select Configuration > Remote Access VPN > Network (Client) Access > Address Assignment > Assignment Policy Configuring Local IP Address Pools To configure IPv4 or IPv6 address pools for VPN remote access tunnels, open ASDM and select Configuration > Remote Access VPN > Network (Client) Access > Address Management > Address Pools > Add/Edit IP Pool. To delete an address pool, open ASDM and select Configuration > Remote Access VPN > Network (Client) Access > Address Management > Address Pools. Select the address pool you want to delete and click Delete. The ASA uses address pools based on the connection profile or group policy for the connection. The order in which you specify the pools is important. If you configure more than one address pool for a connection profile or group policy, the ASA uses them in the order in which you added them to the ASA. If you assign addresses from a non-local subnet, we suggest that you add pools that fall on subnet boundaries to make adding routes for these networks easier. Use one of these methods to configure a local IP address pool: • Configuring Local IPv4 Address Pools Using ASDM, page 5-3 • Configuring Local IPv6 Address Pools Using ASDM, page 5-4 Configuring Local IPv4 Address Pools Using ASDM The IP Pool area shows each configured address pool by name with their IP address range, for example: 10.10.147.100 to 10.10.147.177. If no pools exist, the area is empty. The ASA uses these pools in the order listed: if all addresses in the first pool have been assigned, it uses the next pool, and so on. If you assign addresses from a non-local subnet, we suggest that you add pools that fall on subnet boundaries to make adding routes for these networks easier. Step 1 Select Configuration > Remote Access VPN > Network (Client) Access > Address Assignment > Address Pools. Step 2 To add an IPv4 address, click Add > IPv4 Address pool. To edit an existing address pool, select the address pool in the address pool table and click Edit. Cisco ASA Series VPN ASDM Configuration Guide 5-3 Chapter 5 Configuring IP Addresses for VPNs Configuring Local IP Address Pools Step 3 In the Add/Edit IP Pool dialog box enter this information: • Pool Name—Enter the name of the address pool. It can be up to 64 characters • Starting Address—Enter the first IP address available in each configured pool. Use dotted decimal notation, for example: 10.10.147.100. • Ending Address—Enter the last IP address available in each configured pool. User dotted decimal notation, for example: 10.10.147.177. • Subnet Mask—Identifies the subnet on which this IP address pool resides. Step 4 Click Apply. Step 5 Click OK. Configuring Local IPv6 Address Pools Using ASDM The IP Pool area shows each configured address pool by name with a starting IP address range, the address prefix, and the number of addresses configurable in the pool. If no pools exist, the area is empty. The ASA uses these pools in the order listed: if all addresses in the first pool have been assigned, it uses the next pool, and so on. If you assign addresses from a non-local subnet, we suggest that you add pools that fall on subnet boundaries to make adding routes for these networks easier. Step 1 Select Configuration > Remote Access VPN > Network (Client) Access > Address Assignment > Address Pools. Step 2 To add an IPv6 address, click Add > IPv6 Address pool. To edit an existing address pool, select the address pool in the address pool table and click Edit. Step 3 In the Add/Edit IP Pool dialog box enter this information: • Name—Displays the name of each configured address pool. • Starting IP Address—Enter the first IP address available in the configured pool. For example: 2001:DB8::1. • Prefix Length— Enter the IP address prefix length in bits. For example 32 represents /32 in CIDR notation. The prefix length defines the subnet on which the pool of IP addresses resides. • Number of Addresses—Identifies the number of IPv6 addresses, starting at the Starting IP Address, there are in the pool. Step 4 Click Apply. Step 5 Click OK. Cisco ASA Series VPN ASDM Configuration Guide 5-4 Chapter 5 Configuring IP Addresses for VPNs Configuring DHCP Addressing Configuring DHCP Addressing To use DHCP to assign addresses for VPN clients, you must first configure a DHCP server and the range of IP addresses that the DHCP server can use. Then you define the DHCP server on a connection profile basis. Optionally, you can also define a DHCP network scope in the group policy associated with a connection profile or username. This is either an IP network number or IP Address that identifies to the DHCP server which pool of IP addresses to use. The following examples define the DHCP server at IP address 172.33.44.19 for the connection profile named firstgroup. They also define a DHCP network scope of 192.86.0.0 for the group policy called remotegroup. (The group policy called remotegroup is associated with the connection profile called firstgroup). If you do not define a network scope, the DHCP server assigns IP addresses in the order of the address pools configured. It goes through the pools until it identifies an unassigned address. The following configuration includes more steps than are necessary, in that previously you might have named and defined the connection profile type as remote access, and named and identified the group policy as internal or external. These steps appear in the following examples as a reminder that you have no access to subsequent tunnel-group and group-policy commands until you set these values. Guidelines and Limitations You can only use an IPv4 address to identify a DHCP server to assign client addresses. Assigning IP addresses using DHCP Configure your DHCP servers, then create group policies that use those servers. When a user selects that that group policy, the DHCP server will assign an address for the VPN connection. Configure Your DHCP Servers DHCP server, configure the IP address Assignment policy to use DHCP follow the instructions below. You cannot assign IPv6 addresses to AnyConnect clients using a DHCP server. Step 1 Connect to the ASA using ASDM. Step 2 Verify that DHCP is enabled on Configuration > Remote Access VPN > Network (Client) Access > Address Assignment > Assignment Policy. Step 3 Configure your DHCP servers by selecting Configuration > Remote Access VPN > DHCP Server. Assign the DHCP IP Addressing to a Group Policy Step 1 Select Configuration > Remote Access VPN > Network (Client) Access> AnyConnect Connection Profiles. Step 2 In the Connection Profiles Area click Add or Edit. Step 3 Click Basic in the configuration tree for the connection profile. Step 4 In the Client Address Assignment area, enter the IPv4 address of the DHCP server you want to use to assign IP addresses to clients. For example, 172.33.44.19. Cisco ASA Series VPN ASDM Configuration Guide 5-5 Chapter 5 Configuring IP Addresses for VPNs Assigning IP Addresses to Local Users Step 5 Edit the group-policy associated with the connection profile to define the DHCP scope. Select Configuration > Remote Access VPN > Network (Client) Access> Group Policies. Step 6 Double-click the group policy you want to edit. Step 7 Click Servers in the configuration tree. Step 8 Expand the More Options area by clicking the down arrow. Step 9 Uncheck DHCP Scope Inherit. Step 10 Enter the IP network number or IP Address that identifies to the DHCP server which pool of IP addresses to use. For example, 192.86.0.0. Step 11 Click OK. Step 12 Click Apply. Assigning IP Addresses to Local Users Local user accounts can be configured to use a group policy, and some AnyConnect attributes can also be configured. These user accounts provide fallback if the other sources of IP address fail, so administrators will still have access. This section describes how to configure all the attributes of a local user. Prerequisites This procedure describes how to edit an existing user. To add a user select Configuration > Remote Access VPN > AAA/Local Users > Local Users and click Add. For more information see “Adding a User Account to the Local Database” in Chapter 42, Configuring AAA Servers and the Local Database in the Cisco ASA 5500 Configuration Guide Using ASDM. User Edits By default, the Inherit check box is checked for each setting on the Edit User Account screen, which means that the user account inherits the value of that setting from the default group policy, DfltGrpPolicy. To override each setting, uncheck the Inherit check box, and enter a new value. The detailed steps that follow describe each of the settings on the Edit User Account screen. Detailed Steps Step 1 Start ASDM and select Configuration > Remote Access VPN > AAA/Local Users > Local Users. Step 2 Select the user you want to configure and click Edit. The Edit User Account screen opens. Step 3 In the left pane, click VPN Policy. Step 4 Specify a group policy for the user. The user policy will inherit the attributes of this group policy. If there are other fields on this screen that are set to Inherit the configuration from the Default Group Policy, the attributes specified in this group policy will take precedence over those in the Default Group Policy. Cisco ASA Series VPN ASDM Configuration Guide 5-6 Chapter 5 Configuring IP Addresses for VPNs Assigning IP Addresses to Local Users Step 5 Specify which tunneling protocols are available for the user, or whether the value is inherited from the group policy. Check the desired Tunneling Protocols check boxes to choose the VPN tunneling protocols that are available for use. Only the selected protocols are available for use. The choices are as follows: • Clientless SSL VPN (VPN via SSL/TLS) uses a web browser to establish a secure remote-access tunnel to a VPN Concentrator; requires neither a software nor hardware client. Clientless SSL VPN can provide easy access to a broad range of enterprise resources, including corporate websites, web-enabled applications, NT/AD file shares (web-enabled), e-mail, and other TCP-based applications from almost any computer that can reach HTTPS Internet sites. • The SSL VPN Client lets users connect after downloading the Cisco AnyConnect Client application. Users use a clientless SSL VPN connection to download this application the first time. Client updates then occur automatically as needed whenever the user connects. • IPsec IKEv1—IP Security Protocol. Regarded as the most secure protocol, IPsec provides the most complete architecture for VPN tunnels. Both Site-to-Site (peer-to-peer) connections and Cisco VPN client-to-LAN connections can use IPsec IKEv1. • IPsec IKEv2—IPsec IKEv2-Supported by the AnyConnect Secure Mobility Client. AnyConnect connections using IPsec with IKEv2 can make use of the same feature set available to SSL VPN Connections. • L2TP over IPsec allows remote users with VPN clients provided with several common PC and mobile PC operating systems to establish secure connections over the public IP network to the ASA and private corporate networks. Note Step 6 If no protocol is selected, an error message appears. Specify which filter (IPv4 or IPv6) to use, or whether to inherit the value from the group policy. Filters consist of rules that determine whether to allow or reject tunneled data packets coming through the ASA, based on criteria such as source address, destination address, and protocol. To configure filters and rules, choose Configuration > Remote Access VPN > Network (Client) Access > Group Policies > Add/Edit > General > More Options > Filter. Click Manage to display the ACL Manager pane, on which you can add, edit, and delete ACLs and ACEs. Step 7 Specify whether to inherit the Connection Profile (tunnel group) lock or to use the selected tunnel group lock, if any. Selecting a specific lock restricts users to remote access through this group only. Tunnel Group Lock restricts users by checking if the group configured in the VPN client is the same as the users assigned group. If it is not, the ASA prevents the user from connecting. If the Inherit check box is not checked, the default value is None. Step 8 Specify whether to inherit the Store Password on Client System setting from the group. Uncheck the Inherit check box to activate the Yes and No radio buttons. Click Yes to store the logon password on the client system (potentially a less-secure option). Click No (the default) to require the user to enter the password with each connection. For maximum security, we recommend that you not allow password storage. Step 9 Specify an Access Hours policy to apply to this user, create a new access hours policy for the user, or leave the Inherit box checked. The default value is Inherit, or, if the Inherit check box is not checked, the default value is Unrestricted. Click Manage to open the Add Time Range dialog box, in which you can specify a new set of access hours. Cisco ASA Series VPN ASDM Configuration Guide 5-7 Chapter 5 Configuring IP Addresses for VPNs Assigning IP Addresses to Local Users Step 10 Specify the number of simultaneous logons by the user. The Simultaneous logons parameter specifies the maximum number of simultaneous logons allowed for this user. The default value is 3. The minimum value is 0, which disables logon and prevents user access. Note While there is no maximum limit, allowing several simultaneous connections could compromise security and affect performance. Step 11 Specify the maximum connection time for the user connection time in minutes. At the end of this time, the system terminates the connection. The minimum is 1 minute, and the maximum is 2147483647 minutes (over 4000 years). To allow unlimited connection time, check the Unlimited check box (the default). Step 12 Specify the Idle Timeout for the user in minutes. If there is no communication activity on the connection by this user in this period, the system terminates the connection. The minimum time is 1 minute, and the maximum time is 10080 minutes. This value does not apply to users of clientless SSL VPN connections. Step 13 Configure the Session Alert Interval. If you uncheck the Inherit check box, the Default checkbox is checked automatically. This sets the session alert interval to 30 minutes. If you want to specify a new value, uncheck the Default check box and specify a session alert interval from 1 to 30 minutes in the minutes box. Step 14 Configure the Idle Alert Interval. If you uncheck the Inherit check box, the Default checkbox is checked automatically. This sets the idle alert interval to 30 minutes. If you want to specify a new value, uncheck the Default check box and specify a session alert interval from 1 to 30 minutes in the minutes box. Step 15 To set a dedicated IPv4 address for this user, enter an IPv4 address and subnet mask in the Dedicated IPv4 Address (Optional) area. Step 16 To set a dedicated IPv6 address for this user, enter an IPv6 address with an IPv6 prefix in the Dedicated IPv6 Address (Optional) field. The IPv6 prefix indicates the subnet on which the IPv6 address resides. Step 17 To configure clientless SSL settings, in the left pane, click Clientless SSL VPN. To override each setting, uncheck the Inherit check box, and enter a new value. Step 18 Click Apply. The changes are saved to the running configuration. Cisco ASA Series VPN ASDM Configuration Guide 5-8 CH AP TE R 6 Configuring Dynamic Access Policies This chapter describes how to configure dynamic access policies. It includes the following sections. • Information About Dynamic Access Policies, page 6-1 • Licensing Requirements for Dynamic Access Policies, page 6-3 • Dynamic Access Policies Interface, page 6-4 • Configuring Dynamic Access Policies, page 6-6 • Testing Dynamic Access Policies, page 6-8 • DAP and Authentication, Authorization, and Accounting Services, page 6-9 • Configuring Endpoint Attributes Used in DAPs, page 6-13 • Configuring DAP Access and Authorization Policy Attributes, page 6-27 • Guide to Creating DAP Logical Expressions using LUA, page 6-31 Information About Dynamic Access Policies VPN gateways operate in dynamic environments. Multiple variables can affect each VPN connection, for example, intranet configurations that frequently change, the various roles each user may inhabit within an organization, and logins from remote access sites with different configurations and levels of security. The task of authorizing users is much more complicated in a VPN environment than it is in a network with a static configuration. Dynamic access policies (DAP) on the ASA let you configure authorization that addresses these many variables. You create a dynamic access policy by setting a collection of access control attributes that you associate with a specific user tunnel or session. These attributes address issues of multiple group membership and endpoint security. That is, the ASA grants access to a particular user for a particular session based on the policies you define. The ASA generates a DAP at the time the user connects by selecting and/or aggregating attributes from one or more DAP records. It selects these DAP records based on the endpoint security information of the remote device and the AAA authorization information for the authenticated user. It then applies the DAP record to the user tunnel or session. The DAP system includes the following components that require your attention: • DAP Selection Configuration File—A text file containing criteria that the ASA uses for selecting and applying DAP records during session establishment. Stored on the ASA. You can use ASDM to modify it and upload it to the ASA in XML data format. DAP selection configuration files include all of the attributes that you configure. These can include AAA attributes, endpoint attributes, and access policies as configured in network and web-type ACL filter, port forwarding and URL lists. Cisco ASA Series VPN ASDM Configuration Guide 6-1 Chapter 6 Configuring Dynamic Access Policies Information About Dynamic Access Policies • DfltAccess Policy—Always the last entry in the DAP summary table, always with a priority of 0. You can configure Access Policy attributes for the default access policy, but it does not contain—and you cannot configure—AAA or endpoint attributes. You cannot delete the DfltAccessPolicy, and it must be the last entry in the summary table. Refer to the Dynamic Access Deployment Guide (https://supportforums.cisco.com/docs/DOC-1369) for additional information. DAP and Endpoint Security The ASA obtains endpoint security attributes by using posture assessment tools that you configure. These posture assessment tools include the AnyConnect posture module, the independent Host Scan package, Cisco Secure Desktop, and NAC. Table 6-1 identifies each of the remote access protocols DAP supports, the posture assessment tools available for that method, and the information that tool provides. Table 6-1 DAP Posture Assessment AnyConnect Posture Module Host Scan package Cisco Secure Desktop (without Endpoint Assessment Host Scan Extension enabled) AnyConnect Posture Module Host Scan package Cisco Secure Desktop (with Endpoint Assessment Host Scan Extension enabled) NAC Returns file information, registry key values, running processes, operating system Returns antivirus, antispyware, and personal firewall software information Returns NAC Returns VLAN status Type and VLAN IDs IPsec VPN No No Yes Yes Cisco AnyConnect VPN Yes Yes Yes Yes Clientless VPN Yes Yes No No PIX Cut-through Proxy No No No No Remote Access Protocol Cisco NAC Appliance DAP Support for Remote Access Connection Types The DAP system supports the following remote access methods: • IPsec VPN • Clientless (browser-based) SSL VPN • Cisco AnyConnect Secure Mobility Client (SSL VPN) • PIX cut-through proxy (posture assessment not available) Remote Access Connection Sequence with DAPs The following sequence outlines a typical remote access connection establishment. 1. A remote client attempts a VPN connection. 2. The ASA performs posture assessment, using configured NAC and Cisco Secure Desktop Host Scan values. Cisco ASA Series VPN ASDM Configuration Guide 6-2 Chapter 6 Configuring Dynamic Access Policies Licensing Requirements for Dynamic Access Policies 3. The ASA authenticates the user via AAA. The AAA server also returns authorization attributes for the user. 4. The ASA applies AAA authorization attributes to the session, and establishes the VPN tunnel. 5. The ASA selects DAP records based on the user AAA authorization information and the session posture assessment information. 6. The ASA aggregates DAP attributes from the selected DAP records, and they become the DAP policy. 7. The ASA applies the DAP policy to the session. Licensing Requirements for Dynamic Access Policies The following tables shows the licensing requirements for enforcing Dynamic Access Policies. Advanced Endpoint Assessment license Note This feature is not available on No Payload Encryption models. Model License Requirement All models Advanced Endpoint Assessment License. SSL VPN license (client) Note This feature is not available on No Payload Encryption models. Model License Requirement All models AnyConnect Premium License AnyConnect Mobile License Note This feature is not available on No Payload Encryption models. Cisco ASA Series VPN ASDM Configuration Guide 6-3 Chapter 6 Configuring Dynamic Access Policies Dynamic Access Policies Interface Model License Requirement All models AnyConnect Mobile license.1 1. This license requires activation of one of the following licenses to specify the total number of SSL VPN sessions permitted: AnyConnect Essentials or AnyConnect Premium. Dynamic Access Policies Interface Figure 6-1 shows the Dynamic Access Policies pane. Figure 6-1 Dynamic Access Policies ASDM pane Fields • ACL Priority—Displays the priority of the DAP record. The ASA uses this value to logically sequence the ACLs when aggregating the network and web-type ACLs from multiple DAP records. The ASA orders the records from highest to lowest priority number, with lowest at the bottom of the table. Higher numbers have a higher priority, that is a DAP record with a value of 4 has a higher priority than a record with a value of 2. You cannot manually sort them. • Name—Displays the name of the DAP record. Cisco ASA Series VPN ASDM Configuration Guide 6-4 Chapter 6 Configuring Dynamic Access Policies Dynamic Access Policies Interface • Network ACL List—Displays the name of the firewall ACL that applies to the session. • Web-Type ACL List—Displays the name of the SSL VPN ACL that applies to the session. • Description—Describes the purpose of the DAP record. • Test Dynamic Access Policies button—Click to test already configured DAP records. • Find — You can search for a Dynamic Access Policy (DAP) by using the Find field. Start typing in the field and the tool will search the beginning characters of every field of the DAP table for a match. You can use wild cards to expand your search. For example typing sal in the Find field will match a DAP named Sales but not a DAP named the Find field, the search will find the first instance of either Sales or Wholesalers in the table. Wholesalers. If you type *sal in • Find Arrows — Use the up and down arrows to skip up or down to the next string match. • Match Case — Checking the Match Case check box will make your search case-sensitive. Figure 6-2 shows the Add Dynamic Access Policy pane. Figure 6-2 Add/Edit Dynamic Access Policies Pane Cisco ASA Series VPN ASDM Configuration Guide 6-5 Chapter 6 Configuring Dynamic Access Policies Configuring Dynamic Access Policies Configuring Dynamic Access Policies Prerequisites • Other than where noted, you must install Cisco Secure Desktop or Host Scan before configuring DAP endpoint attributes. • Before configuring File, Process, and Registry endpoint attributes, configure File, Process, and Registry Basic Host Scan attributes. For instructions, start ASDM and select Configuration > Remote Access VPN > Secure Desktop Manager > Host Scan and click Help. Guidelines and Limitations DAP supports only ASCII characters. Mobile Device Guidelines ASA administrators will use AnyConnect Mobile Posture DAP Attributes differently depending on the AnyConnect license they have installed. See Adding Mobile Posture Attributes to a DAP, page 6-16 for more information. Detailed Steps Step 1 Start ASDM and select Configuration > Remote Access VPN > Network (Client) Access or Clientless SSL VPN Access > Dynamic Access Policies. The Configure Dynamic Access Policies pane opens. Step 2 To include certain antivirus, antispyware, or personal firewall endpoint attributes, click the CSD configuration link near the top of the pane. Then enable Cisco Secure Desktop and Host Scan extensions. This link does not display if you have previously enabled both of these features. If you enable Cisco Secure Desktop, but do not enable Host Scan extensions, when you apply your changes ASDM includes a link to enable Host Scan configuration. Step 3 To create a new dynamic access policy, click Add. To modify an existing policy, click Edit. The Add/Edit Dynamic Access Policy pane opens. Step 4 Step 5 At the top of the Add/Edit Dynamic Access Policy pane, provide a name (required) and a description (optional) of this dynamic access policy. • The Policy Name is a string of 4 through 32 characters, no spaces allowed. • You are allowed a maximum of 80 charaters in the DAP Description field. In the ACL Priority field, set a priority for the dynamic access policy. The security appliance applies access policies in the order you set here, highest number having the highest priority. Values of 0 to 2147483647 are valid. The default value is 0. Step 6 In the Add/Edit AAA Attributes field, use the ANY/ALL/NONE drop-down list (unlabeled) to choose whether a user must have any, all, or none of the AAA attribute values you configure to use this dynamic access policy, as well as satisfying every endpoint attribute. Duplicate entries are not allowed. If you configure a DAP record with no AAA or endpoint attributes, the ASA always selects it since all selection criteria are satisfied. Step 7 To Set AAA attributes, click Add or Edit in the AAA Attributes field. Use one or more of these procedures: See the “Configuring AAA Attributes in a DAP” section on page 6-9 for more information. Cisco ASA Series VPN ASDM Configuration Guide 6-6 Chapter 6 Configuring Dynamic Access Policies Configuring Dynamic Access Policies Step 8 Use one or more of these procedures to add or edit endpoint attributes to the DAP policy: • Adding an Anti-Spyware or Anti-Virus Endpoint Attribute to a DAP, page 6-14 • Adding an Application Attribute to a DAP, page 6-15 • Adding Mobile Posture Attributes to a DAP, page 6-16 • Adding a File Endpoint Attribute to a DAP, page 6-17 • Adding a Device Endpoint Attribute to a DAP, page 6-18 • Adding a NAC Endpoint Attribute to a DAP, page 6-19 • Adding an Operating System Endpoint Attribute to a DAP, page 6-20 • Adding a Personal Firewall Endpoint Attribute to a DAP, page 6-20 • Adding a Policy Endpoint Attribute to a DAP, page 6-21 • Adding a Process Endpoint Attribute to a DAP, page 6-22 • Adding a Registry Endpoint Attribute to a DAP, page 6-23 You can create multiple instances of each type of endpoint attribute. For each of these types, you need to decide whether the DAP policy should require that the user have all instances of a type (Match all = AND) or only one of them (Match Any = OR). To set this value for each of the end point attributes, click the Logical Op. button. Step 9 In the Advanced field you can enter one or more logical expressions to set AAA or endpoint attributes other than what is possible in the AAA and Endpoint areas above. This feature that requires knowledge of the Lua programming language. • AND/OR—Click to define the relationship between the basic selection rules and the logical expressions you enter here, that is, whether the new attributes add to or substitute for the AAA and endpoint attributes already set. The default is AND. • Logical Expressions—You can configure multiple instances of each type of endpoint attribute. Enter free-form Lua text that defines new AAA and/or endpoint selection attributes. ASDM does not validate text that you enter here; it just copies this text to the DAP XML file, and the ASA processes it, discarding any expressions it cannot parse. • Guide—Click to display online help for creating these logical operations or see Guide to Creating DAP Logical Expressions using LUA, page 6-31. Step 10 To configure network and webtype ACLs, file browsing, file server entry, HTTP proxy, URL entry, port forwarding lists and URL lists, set values in the Access Policy Attributes fields. Attribute values that you configure here override authorization values in the AAA system, including those in existing user, group, tunnel group, and default group records. See Configuring DAP Access and Authorization Policy Attributes, page 6-27 for more information. Step 11 Click OK. Tip If you want to test your Dynamic Access Policy, in the Configure Dynamic Access Policies dialog box, click Test Dynamic Access Policies and add the attributes to the test interface. See Testing Dynamic Access Policies, page 6-8. Cisco ASA Series VPN ASDM Configuration Guide 6-7 Chapter 6 Configuring Dynamic Access Policies Testing Dynamic Access Policies Testing Dynamic Access Policies Figure 6-3 Test Dynamic Access Policies Pane This pane lets you test the retrieval of the set of DAP records configured on the device by specifying authorization attribute value pairs. To specify these pairs, use the Add/Edit buttons associated with the AAA Attribute and Endpoint Attribute tables. The dialogs that display when you click these Add/Edit buttons are similar to those in the Add/Edit AAA Attributes and Add/Edit Endpoint Attributes dialog boxes. When you enter attribute value pairs and click the “Test” button, the DAP subsystem on the device references these values when evaluating the AAA and endpoint selection attributes for each record. The results display in the “Test Results” text area. Fields • Selection Criteria—Determine the AAA and endpoint attributes to test for dynamic access policy retrieval. • AAA Attributes – AAA Attribute—Identifies the AAA attribute. – Operation Value—Identifies the attribute as =/!= to the given value. – Add/Edit—Click to add or edit a AAA attribute. • Endpoint Attributes—Identifies the endpoint attribute. – Endpoint ID—Provides the endpoint attribute ID. – Name/Operation/Value— – Add/Edit/Delete—Click to add, edit or delete and endpoint attribute. Cisco ASA Series VPN ASDM Configuration Guide 6-8 Chapter 6 Configuring Dynamic Access Policies DAP and Authentication, Authorization, and Accounting Services • Test Result—Displays the result of the test. • Test—Click to test the retrieval of the policies you have set. • Close—Click to close the pane. DAP and Authentication, Authorization, and Accounting Services DAP complements AAA services. It provides a limited set of authorization attributes that can override those AAA provides. The ASA selects DAP records based on the AAA authorization information for the user and posture assessment information for the session. The ASA can select multiple DAP records depending on this information, which it then aggregates to create DAP authorization attributes. You can specify AAA attributes from the Cisco AAA attribute hierarchy, or from the full set of response attributes that the ASA receives from a RADIUS or LDAP server. For more information about DAP and AAA, see the section, Configuring AAA Attributes in a DAP. Configuring AAA Attributes in a DAP Figure 6-4 shows the Add AAA Attribute dialog box. Figure 6-4 Add AAA Attribute Dialog Box To configure AAA attributes as selection criteria for DAP records, in the Add/Edit AAA Attributes dialog box, set the Cisco, LDAP, or RADIUS attributes that you want to use. You can set these attributes either to = or != the value you enter. There is no limit for the number of AAA attributes for each DAP record. For detailed information about AAA attributes, see AAA Attribute Definitions. Fields AAA Attributes Type—Use the drop-down list to select Cisco, LDAP or RADIUS attributes: • Cisco—Refers to user authorization attributes that are stored in the AAA hierarchical model. You can specify a small subset of these attributes for the AAA selection attributes in the DAP record.These include: – Group Policy —The group policy name associated with the VPN user session. Can be set locally on the security appliance or sent from a RADIUS/LDAP server as the IETF-Class (25) attribute. Maximum 64 characters. Cisco ASA Series VPN ASDM Configuration Guide 6-9 Chapter 6 Configuring Dynamic Access Policies DAP and Authentication, Authorization, and Accounting Services – Assigned IP Address—Enter the IPv4 address you want to specify for the policy. The assigned IP address for full tunnel VPN clients (IPsec, L2TP/IPsec, SSL VPN AnyConnect) does not apply to Clientless SSL VPN, since there is no address assignment for clientless sessions. – Assigned IPv6 Address—Enter the IPv6 address you want to specify for the policy. – Connection Profile—The connection or tunnel group name. Maximum 64 characters. – Username—The username of the authenticated user. Maximum 64 characters. Applies if you are using Local, RADIUS, LDAP authentication/authorization or any other authentication type (for example, RSA/SDI), NT Domain, etc). – =/!=—Equal to/Not equal to. • LDAP—The LDAP client (security appliance) stores all native LDAP response attribute value pairs in a database associated with the AAA session for the user. The LDAP client writes the response attributes to the database in the order in which it receives them. It discards all subsequent attributes with that name. This scenario might occur when a user record and a group record are both read from the LDAP server. The user record attributes are read first, and always have priority over group record attributes. To support Active Directory group membership, the AAA LDAP client provides special handling of the LDAP memberOf response attribute. The AD memberOf attribute specifies the DN string of a group record in AD. The name of the group is the first CN value in the DN string. The LDAP client extracts the group name from the DN string and stores it as the AAA memberOf attribute, and in the response attribute database as the LDAP memberOf attribute. If there are additional memberOf attributes in the LDAP response message, then the group name is extracted from those attributes and is combined with the earlier AAA memberOf attribute to form a comma separated string of group names, also updated in the response attribute database. In the case where the VPN remote access session to an LDAP authentication/authorization server returns the following three Active directory groups (memberOf enumerations): cn=Engineering,ou=People,dc=company,dc=com cn=Employees,ou=People,dc=company,dc=com cn=EastCoastast,ou=People,dc=company,dc=com the ASA processes three Active Directory groups: Engineering, Employees, and EastCoast which could be used in any combination as aaa.ldap selection criteria. LDAP attributes consist of an attribute name and attribute value pair in the DAP record. The LDAP attribute name is syntax/case sensitive. If for example you specify LDAP attribute Department instead of what the AD server returns as department, the DAP record will not match based on this attribute setting. Note To enter multiple values in the Value field, use the semicolon (;) as the delimiter. For example: eng;sale; cn=Audgen VPN,ou=USERS,o=OAG • RADIUS—The RADIUS client stores all native RADIUS response attribute value pairs in a database associated with the AAA session for the user. The RADIUS client writes the response attributes to the database in the order in which it receives them. It discards all subsequent attributes with that name. This scenario might occur when a user record and a group record are both read from the RADIUS server. The user record attributes are read first, and always have priority over group record attributes. Cisco ASA Series VPN ASDM Configuration Guide 6-10 Chapter 6 Configuring Dynamic Access Policies DAP and Authentication, Authorization, and Accounting Services RADIUS attributes consist of an attribute number and attribute value pair in the DAP record. See Security Appliance Supported RADIUS Attributes and Values for a table that lists RADIUS attributes that the security appliance supports. Note For RADIUS attributes, DAP defines the Attribute ID = 4096 + RADIUS ID. For example: The RADIUS attribute "Access Hours" has a Radius ID = 1, therefore DAP attribute value = 4096 + 1 = 4097. The RADIUS attribute "Member Of" has a Radius ID = 146, therefore DAP attribute value = 4096 + 146 = 4242. • LDAP and RADIUS attributes include: – Attribute ID—Names/numbers the attribute. Maximum 64 characters. – Value—The attribute name (LDAP) or number (RADIUS). To enter multiple values in the Value field, use the semicolon (;) as the delimiter. For example: eng;sale; cn=Audgen VPN,ou=USERS,o=OAG – =/!=—Equal to/Not equal to. • LDAP includes the Get AD Groups button. This button queries the Active Directory LDAP server for the list of groups the user belong to (memberOf enumerations). It retrieves the AD groups using the CLI show-ad-groups command in the background The show ad-groups command applies only to Active Directory servers using LDAP. Use this command to display AD groups that you can use for dynamic access policy AAA selection criteria. The default time that the ASA waits for a response from the server is 10 seconds. You can adjust this time using the group-search-timeout command in aaa-server host configuration mode. Note If the Active Directory server has a large number of groups, the output of the show ad-groups command might be truncated based on limitations to the amount of data the server can fit into a response packet. To avoid this problem, use the filter option to reduce the number of groups reported by the server. Retrieving Active Directory Groups Figure 6-5 shows the Retrieve AD Groups from Selected AD Server Group pane. Cisco ASA Series VPN ASDM Configuration Guide 6-11 Chapter 6 Configuring Dynamic Access Policies DAP and Authentication, Authorization, and Accounting Services Figure 6-5 Retrieve AD Groups Dialog Box You can query an Active Directory server for available AD groups in this pane. This feature applies only to Active Directory servers using LDAP. Use the group information to specify dynamic access policy AAA selection criteria. You can change the level in the Active Directory hierarchy where the search begins by changing the Group Base DN in the Edit AAA Server pane. You can also change the time that the ASA waits for a response from the server in the window. To configure these features, choose Configuration > Remote Access VPN > AAA/Local Users > AAA Server Groups > Edit AAA Server. Note If the Active Directory server has a large number of groups, the list of AD groups retrieved may be truncated based on limitations of the amount of data the server can fit into a response packet. To avoid this problem, use the filter feature to reduce the number of groups reported by the server. Fields AD Server Group—The name of the AAA server group to retrieve AD groups. Filter By—Specify a group or the partial name of a group to reduce the groups displayed. Group Name—A list of AD groups retrieved from the server. AAA Attribute Definitions The following table defines the AAA selection attribute names that are available for DAP use. The Attribute Name field shows you how to enter each attribute name in a Lua logical expression, which you might do in the Advanced section of the Add/Edit Dynamic Access Policy pane. Attribute Type Attribute Name Cisco aaa.cisco.grouppolicy AAA Source Value Max String Length string 64 Cisco ASA Series VPN ASDM Configuration Guide 6-12 Description Group policy name on the ASA or sent from a Radius/LDAP server as the IETF-CLass (25) attribute Chapter 6 Configuring Dynamic Access Policies Configuring Endpoint Attributes Used in DAPs aaa.cisco.ipaddress AAA number - Assigned IP address for full tunnel VPN clients (IPsec, L2TP/IPsec, SSL VPN AnyConnect) aaa.cisco.tunnelgroup AAA string 64 Connection profile (tunnel group) name aaa.cisco.username AAA string 64 Name of the authenticated user (applies if using Local authentication/authorization) LDAP aaa.ldap.