Brocade Communications Systems Serveriron Adx 12 4 00A Users Manual Security Guide

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53-1002440-03
June 2012

ServerIron ADX
Security Guide
Supporting Brocade ServerIron ADX version 12.4.00a

®

© 2012 Brocade Communications Systems, Inc. All Rights Reserved.
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Document History
Title

Publication number

Summary of changes

Date

ServerIron ADX Security Guide

53-1002440-01

New document

January, 2012

ServerIron ADX Security Guide

53-1002440-02

Corrections made to ACL
chapter

April, 2012

ServerIron ADX Security Guide

53-1002440-03

Updates made to
documentation.

June, 2012

Contents

About This Document
Audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
Supported hardware and software . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
Document conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
Text formatting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
Notes, cautions, and danger notices . . . . . . . . . . . . . . . . . . . . . xiv
Notice to the reader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiv
Related publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
Getting technical help . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv

Chapter 1

Network Security
TCP SYN attacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
IP TCP syn-proxy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Granular application of syn-proxy feature . . . . . . . . . . . . . . . . . . . . . . 2
Syn-def . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
show server traffic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
SYN-def-dont-send-ack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
show server debug. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
No response to non-SYN first packet of a TCP flow . . . . . . . . . . . . . . 4
Prioritizing management traffic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Protection against attack in hardware . . . . . . . . . . . . . . . . . . . . . 6
Peak BP utilization with TRAP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Show CPU-utilization command enhancement . . . . . . . . . . . . . . 6
BP utilization threshold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
MP utilization threshold. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

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Transaction Rate Limit (TRL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Understanding transaction rate limit . . . . . . . . . . . . . . . . . . . . . . 7
Configuring transaction rate limit . . . . . . . . . . . . . . . . . . . . . . . . . 8
Configuring the maximum number of rules . . . . . . . . . . . . . . . . 12
Saving a TRL configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Transaction rate limit command reference . . . . . . . . . . . . . . . . 13
Global TRL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
TRL plus security ACL-ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
security acl-id . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Transaction rate limit hold-down value. . . . . . . . . . . . . . . . . . . . 15
Displaying TRL rules statistics. . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Displaying TRL rules in a policy. . . . . . . . . . . . . . . . . . . . . . . . . . 15
Displaying IP address with held down traffic . . . . . . . . . . . . . . . 16
Refusing new connections from a specified IP address . . . . . . 16
HTTP TRL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Overview of HTTP TRL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
HTTP TRL features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Configuring HTTP TRL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Configuring HTTP TRL client . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Configuring HTTP TRL defaults . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Sample HTTP TRL configuration . . . . . . . . . . . . . . . . . . . . . . . . . 20
Displaying HTTP TRL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Display all HTTP TRL policies. . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Display HTTP TRL policy from index . . . . . . . . . . . . . . . . . . . . . . 22
Display HTTP TRL policy client. . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Display HTTP TRL policy starting from index . . . . . . . . . . . . . . . 23
Display HTTP TRL policy matching a regular expression . . . . . . 24
Display HTTP TRL policy client index (MP) . . . . . . . . . . . . . . . . . 24
Display HTTP TRL policy client index (BP). . . . . . . . . . . . . . . . . . 25
Display HTTP TRL policy for all client entries (BP) . . . . . . . . . . . 26
Downloading an HTTP TRL policy through TFTP . . . . . . . . . . . . . . . . 26
HTTP TRL policy commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Client-name  monitor-interval . . . . . . . . . . . . . . . 27
Client-name  max-conn . . . . . . . . . . . . . . . . . . . . 27
Client-name  exceed-action . . . . . . . . . . . . . . . . 28
Default monitor-interval. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Default max-conn. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Default exceed-action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Logging for DoS Attacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Configuration commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
show server conn-rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Maximum connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
clear statistics dos-attack. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Maximum concurrent connection limit per client . . . . . . . . . . . . . . . 32
Limiting the number of concurrent connections per client. . . . 32

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Firewall load balancing enhancements . . . . . . . . . . . . . . . . . . . . . . . 34
Enabling firewall strict forwarding. . . . . . . . . . . . . . . . . . . . . . . . 34
Enabling firewall VRRPE priority . . . . . . . . . . . . . . . . . . . . . . . . . 34
Enabling track firewall group. . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Enabling firewall session sync delay. . . . . . . . . . . . . . . . . . . . . . 35
Syn-cookie threshhold trap. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Service port attack protection in hardware. . . . . . . . . . . . . . . . . . . . 35
Traffic segmentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
VLAN bridging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Considerations when configuring VLAN bridging . . . . . . . . . . . . 38
Configuring VLAN bridging. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Displaying VLAN bridge information . . . . . . . . . . . . . . . . . . . . . . 39
Traffic segmentation using the use-session-for-vip-mac command41
DNS attack protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Notes: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Configuring DNS attack protection . . . . . . . . . . . . . . . . . . . . . . . 43
Displaying DNS attack protection information . . . . . . . . . . . . . . 46

Chapter 2

Access Control List
How ServerIron processes ACLs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Prior to release 12.3.01 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Beginning with release 12.3.01 and later . . . . . . . . . . . . . . . . . 49
Rule-based ACLs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
How fragmented packets are processed . . . . . . . . . . . . . . . . . . 51
Default ACL action. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Types of IP ACLs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
ACL IDs and entries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
ACL entries and the Layer 4 CAM. . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Aging out of entries in the Layer 4 CAM . . . . . . . . . . . . . . . . . . . 53
Displaying the number of Layer 4 CAM entries . . . . . . . . . . . . . 53
Specifying the maximum number of CAM entries for rule-based ACLs
54
Configuring numbered and named ACLs. . . . . . . . . . . . . . . . . . . . . . 54
Configuring standard numbered ACLs . . . . . . . . . . . . . . . . . . . . 55
Configuring extended numbered ACLs . . . . . . . . . . . . . . . . . . . . 56
Extended ACL syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Configuring standard or extended named ACLs . . . . . . . . . . . . 62
Displaying ACL definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Displaying ACLs using keywords . . . . . . . . . . . . . . . . . . . . . . . . . 64
Modifying ACLs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Displaying a list of ACL entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Applying an ACLs to interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Reapplying modified ACLs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

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ACL logging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Displaying ACL log entries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Displaying ACL statistics for flow-based ACLs . . . . . . . . . . . . . . 72
Clearing flow-based ACL statistics . . . . . . . . . . . . . . . . . . . . . . . 72
Dropping all fragments that exactly match a flow-based ACL . . . . . 72
Clearing the ACL statistics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Enabling ACL filtering of fragmented packets . . . . . . . . . . . . . . . . . . 73
Filtering fragmented packets for rule-based ACLs. . . . . . . . . . . 73
Enabling hardware filtering for packets denied by flow-based ACLs75
Enabling strict TCP or UDP mode for flow-based ACLs . . . . . . . . . . . 76
Enabling strict TCP mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Enabling strict UDP mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Configuring ACL packet and flow counters. . . . . . . . . . . . . . . . . 78
ACLs and ICMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Using flow-based ACLs to filter ICMP packets based on the IP packet
length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
ICMP filtering with flow-based ACLs . . . . . . . . . . . . . . . . . . . . . . 79
Using ACLs and NAT on the same interface (flow-based ACLs) . . . . 82
Displaying ACL bindings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Troubleshooting rule-based ACLs. . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

Chapter 3

IPv6 Access Control Lists
IACL overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
Configuration Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Processing of IPv6 ACLs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Configuring an IPv6 ACL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Applying an IPv6 ACL to an interface . . . . . . . . . . . . . . . . . . . . . 93
Displaying ACLs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Displaying ACLs bound to an interface. . . . . . . . . . . . . . . . . . . . 94
Using an ACL to Restrict SSH Access. . . . . . . . . . . . . . . . . . . . . . . . . 94
Using an ACL to Restrict Telnet Access . . . . . . . . . . . . . . . . . . . . . . . 95
Logging IPv6 ACLs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

Chapter 4

Network Address Translation
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Configuring NAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Configuring static NAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Configuring dynamic NAT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
NAT configuration examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
PAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103
Forwarding packets without NAT translation. . . . . . . . . . . . . . . . . .103

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Translation timeouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104
Configuring the NAT translation aging timer . . . . . . . . . . . . . .104
Stateless static IP NAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105
Redundancy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105
Enabling IP NAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106
Enabling static NAT redundancy . . . . . . . . . . . . . . . . . . . . . . . .106
Enabling dynamic NAT redundancy . . . . . . . . . . . . . . . . . . . . . 107
Displaying NAT information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Displaying NAT statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .108
Displaying NAT translation. . . . . . . . . . . . . . . . . . . . . . . . . . . . .110
Displaying NAT redundancy information. . . . . . . . . . . . . . . . . .111
Displaying VRRPE information . . . . . . . . . . . . . . . . . . . . . . . . .112
Clearing NAT entries from the table . . . . . . . . . . . . . . . . . . . . . . . . .112

Chapter 5

Syn-Proxy and DoS Protection
Understanding Syn-Proxy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113
Syn-Proxy auto control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113
Difference between ServerIron ADX and JetCore Syn-Proxy Behavior
113
Configuring Syn-Proxy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .114
Setting a minimum MSS value for SYN-ACK packets . . . . . . . 117
Configuring Syn-Proxy auto control . . . . . . . . . . . . . . . . . . . . . .120
Displaying Syn-Proxy Commands . . . . . . . . . . . . . . . . . . . . . . .121
DDoS protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .124
Configuring a security filter . . . . . . . . . . . . . . . . . . . . . . . . . . . .125
Configuring a Generic Rule . . . . . . . . . . . . . . . . . . . . . . . . . . . .125
Configuring a rule for common attack types. . . . . . . . . . . . . .127
Configuring a rule for ip-option attack types . . . . . . . . . . . . . .129
Configuring a rule for icmp-type options . . . . . . . . . . . . . . . . .130
Configuring a rule for IPv6 ICMP types . . . . . . . . . . . . . . . . . . .131
Configuring a rule for IPv6 ext header types . . . . . . . . . . . . . .132
Binding the filter to an interface . . . . . . . . . . . . . . . . . . . . . . . .133
Clearing DOS attack statistics. . . . . . . . . . . . . . . . . . . . . . . . . .133
Clearing all DDOS Filter & Attack Counters . . . . . . . . . . . . . . .133
Logging for DoS attacks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .133
Displaying security filter statistics . . . . . . . . . . . . . . . . . . . . . .134
Address-sweep and port-scan logging . . . . . . . . . . . . . . . . . . .134

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Chapter 6

Secure Socket Layer (SSL) Acceleration
SSL overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .135
Public Key Infrastructure (PKI) . . . . . . . . . . . . . . . . . . . . . . . . .135
Asymmetric cryptography . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136
Certificate Authority (CA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136
Certificate Revocation List (CRL) . . . . . . . . . . . . . . . . . . . . . . .136
Cipher suite . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136
Digital certificate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136
Digital signature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136
Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136
Key pair. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136
Private key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .136
Public key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137
SSL acceleration on the ServerIron ADX . . . . . . . . . . . . . . . . . . . . .137
SSL Termination Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137
SSL Proxy Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138
ServerIron ADX SSL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .138
Configuring SSL on a ServerIron ADX . . . . . . . . . . . . . . . . . . . . . . .140
Obtaining a ServerIron ADX keypair file . . . . . . . . . . . . . . . . . .140
Certificate management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Converting certificate formats. . . . . . . . . . . . . . . . . . . . . . . . . . 147
Importing keys and certificates. . . . . . . . . . . . . . . . . . . . . . . . .148
Support for SSL renegotiation. . . . . . . . . . . . . . . . . . . . . . . . . .164
Basic SSL profile configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . .164
Specifying a keypair file . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165
Specifying a cipher suite . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165
Specifying a certificate file . . . . . . . . . . . . . . . . . . . . . . . . . . . .166
Advanced SSL profile configuration . . . . . . . . . . . . . . . . . . . . . . . . .166
Configuring client authentication . . . . . . . . . . . . . . . . . . . . . . .166
Enabling session caching . . . . . . . . . . . . . . . . . . . . . . . . . . . . .170
Configuring session cache size. . . . . . . . . . . . . . . . . . . . . . . . .170
Configuring a session cache timeout . . . . . . . . . . . . . . . . . . . . 171
Enabling SSL Version 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Enabling close notify . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Disabling certificate verification . . . . . . . . . . . . . . . . . . . . . . . . 171
Enabling a ServerIron ADX SSL to respond with renegotiation
headers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .172
Configuring Real and Virtual Servers for SSL Termination and Proxy Mode
172
Configuring Real and Virtual Servers for SSL Termination Mode173
Configuring Real and Virtual Servers for SSL Proxy Mode . . . 174
Configuration Examples for SSL Termination and Proxy Modes . . 176
Configuring SSL Termination Mode . . . . . . . . . . . . . . . . . . . . . 176
Configuring SSL Proxy Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
TCP configuration issues with SSL Terminate and SSL Proxy .178
Other protocols supported for SSL . . . . . . . . . . . . . . . . . . . . . .184
Configuring the system max values . . . . . . . . . . . . . . . . . . . . .185

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SSL debug and troubleshooting commands . . . . . . . . . . . . . . . . . .187
Diagnostics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .187
Displaying SSL information . . . . . . . . . . . . . . . . . . . . . . . . . . . .188
Displaying the status of a CRL record . . . . . . . . . . . . . . . . . . .191
Displaying socket information . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199
Displaying SSL Statistics information . . . . . . . . . . . . . . . . . . . .201
Displaying TCP IP information . . . . . . . . . . . . . . . . . . . . . . . . . .205
ASM SSL dump commands. . . . . . . . . . . . . . . . . . . . . . . . . . . .209

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About This Document

Audience
This document is designed for system administrators with a working knowledge of Layer 2 and
Layer 3 switching and routing.
If you are using a Brocade Layer 3 Switch, you should be familiar with the following protocols if
applicable to your network – IP, RIP, OSPF, BGP, ISIS, IGMP, PIM, DVMRP, and VRRP.

Supported hardware and software
Although many different software and hardware configurations are tested and supported by
Brocade Communications Systems, Inc. for 12.3 documenting all possible configurations and
scenarios is beyond the scope of this document.
The following hardware platforms are supported by this release of this guide:

•
•
•
•

ServerIron ADX 1000
ServerIron ADX 4000
ServerIron ADX 8000
ServerIron ADX 10000

Document conventions
This section describes text formatting conventions and important notice formats used in this
document.

Text formatting
The narrative-text formatting conventions that are used are as follows:

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bold text

Identifies command names
Identifies the names of user-manipulated GUI elements
Identifies keywords
Identifies text to enter at the GUI or CLI

italic text

Provides emphasis
Identifies variables
Identifies document titles

code text

Identifies CLI output

For readability, command names in the narrative portions of this guide are presented in bold: for
example, show version.

Notes, cautions, and danger notices
The following notices and statements are used in this manual. They are listed below in order of
increasing severity of potential hazards.

NOTE

A note provides a tip, guidance or advice, emphasizes important information, or provides a reference
to related information.

CAUTION
A Caution statement alerts you to situations that can be potentially hazardous to you or cause
damage to hardware, firmware, software, or data.

DANGER
A Danger statement indicates conditions or situations that can be potentially lethal or extremely
hazardous to you. Safety labels are also attached directly to products to warn of these conditions
or situations.

Notice to the reader
This document may contain references to the trademarks of the following corporations. These
trademarks are the properties of their respective companies and corporations.
These references are made for informational purposes only.

xiv

Corporation

Referenced Trademarks and Products

Sun Microsystems

Solaris

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Corporation

Referenced Trademarks and Products

Microsoft Corporation

Windows NT, Windows 2000

The Open Group

Linux

Related publications
The following Brocade documents supplement the information in this guide:

•
•
•
•
•
•
•
•
•
•
•

Release Notes for ServerIron Switch and Router Software TrafficWorks 12.2.00
ServerIron ADX Graphical User Interface
ServerIron ADX Server Load Balancing Guide
ServerIron ADX Advanced Server Load Balancing Guide
ServerIron ADX Global Server Load Balancing Guide
ServerIron ADX Security Guide
ServerIron ADX Administration Guide
ServerIron ADX Switching and Routing Guide
ServerIron ADX Firewall Load Balancing Guide
ServerIron ADX Chassis Hardware Installation Guide
Ironware MIB Reference Manual

Getting technical help
To contact Technical Support, got to http://www.brocade.com/services-support/index.page for the
latest e-mail and telephone contact information..

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Chapter

Network Security

1

TCP SYN attacks
ServerIron software contains many intrusion detection and prevention capabilities. The ServerIron
can be configured to defend against a variety of TCP SYN attacks, Denial of Service (DoS) attacks,
and Smurf attacks.
TCP SYN attacks disrupt normal traffic flow by exploiting the way TCP connections are established.
When a normal TCP connection occurs, the connecting host first sends a TCP SYN packet to the
destination host. The destination host (actually the ServerIron, acting as an intermediary between
the source and destination hosts) responds with a SYN ACK packet. The connecting host then
returns an ACK packet. This process, known as a “TCP three-way handshake”, establishes the TCP
connection.
A TCP SYN attack floods a host with TCP SYN packets. For each of these TCP SYN packets, the
ServerIron responds with a SYN ACK packet and adds an entry to its session table. However, no
ACK packet is actually sent back, so the connection is incomplete. If the attacker sends enough
TCP SYN packets, the session table fills up with incomplete connections, and service can be denied
to legitimate TCP connections.
syn-proxy

IP TCP syn-proxy
Configure the ip tcp syn-proxy command as shown in the following.
1. Configure syn-proxy in the global mode.
ServerIronADX(config)# ip tcp syn-proxy

Syntax: ip tcp syn-proxy

NOTE

You must configure ip tcp syn-proxy command only at the global level, to turn on and off the
global syn-proxy flag.
2. Enable syn-proxy on each interface handling inbound SYN requests (no change here).
ServerIronADX(config)#interface e 3/1
ServerIronADX(config-if-3/1)# ip tcp syn-proxy in

Usage guidelines:
• The default value for a valid ACK time is 32 seconds and is not user configurable.

• If you enter a value, it is ignored. The command remains in the config file the way you enter it,
in case you need to downgrade to the previous release.

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Granular application of syn-proxy feature

• ServerIron may accept the ACK during 33 seconds to 64 seconds due to the syn-proxy
algorithm, but it does not accept the ACK after 64 seconds.

• If you enter a value for the ip tcp syn-proxy  command from the CLI or upgrade from an
older release such as 09.4.x to 09.5.2a with the ip tcp syn-proxy  command in the
config file, you receive the following warning message.
Warning: The value 10 is being ignored.
Default ACK validate time of 32 seconds will be used.
To change the MSL value, issue 'server msl '.

Granular application of syn-proxy feature
This feature applies to ServerIron ADX Syn-Proxy. When this feature is enabled, traffic destined to a
virtual server IP is denied if the destination port is not defined under any of the virtual server
definitions.
This feature prevents ServerIron ADX from responding with TCP SYN-ACK to TCP SYN for ports not
defined under VIP.
Use the following command to validate traffic against a configured virtual port.
ServerIronADX(config)# server syn-cookie-check-vport

Syntax: [no] server syn-cookie-check-vport

Syn-def
Introduction
Use SYN-def (also known as SYN-Defense) to protect the hosts behind the ServerIron (not the
ServerIron itself) by the ServerIron to complete the TCP three-way handshake on behalf of a
connecting client. There is no SYN-cookie functionality with SYN-def.

NOTE
SYN-Defense is recommened for only where Direct Server Return (DSR) is used. DSR is not
supported with SYN-proxy and is supported with SYN-def. For non DSR scenarios, use Syn-Proxy only.

show server traffic
Use the show server traffic command to display information about the number of times the
incomplete connection threshold was reached.

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Syn-def

ServerIronADX# show server traffic
Client->Server
=
0 Server->Client
Drops
=
0 Aged
Fw_drops
=
0 Rev_drops
FIN_or_RST
=
0 old-conn
Disable_drop
=
0 Exceed_drop
Stale_drop
=
0 Unsuccessful
TCP SYN-DEF RST
=
0 Server Resets
Out of Memory
=
0 Out of Memory

=
=
=
=
=
=
=
=

1

0
0
0
0
0
0
0
0

The last line contains information relevant to the incomplete connection threshold. The TCP
SYN-DEF RST field displays the number of times the incomplete connection threshold was reached.
The Server Resets field displays the number of times the ServerIron sent a TCP RESET packet to
the destination real server.

SYN-def-dont-send-ack
The SYN-def feature allows the ServerIron to complete the TCP three-way handshake on behalf of a
connecting client. When a connecting client sends a TCP SYN to a server, the ServerIron forwards
the SYN to the real server, then forwards the SYN ACK from the server to the client. Next, the
ServerIron sends an ACK to the real server, completing the three-way handshake on behalf of the
connecting client. This action allows the real server to move the connection from its pending
connection queue to its established (and much larger) connection queue.
Use the server syn-def-dont-send-ack command to prevent the ServerIron from sending the ACK to
the real server to complete the three-way handshake.
Example
ServerIronADX(config)#server syn-def-dont-send-ack

show server debug
Use the show server debug command to display information about the configuration, as shown in
the following example.

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No response to non-SYN first packet of a TCP flow

SLB-chassis1/1#show server debug

Generic Deug Info
BP Distribution
No of BPs
Partner Chassis MAC
Partner BP1 MAC
Partner BP3 MAC
Partner BP5 MAC

=
=
=
=
=
=

Enabled
3
0000.0000.0000
0000.0000.0000
0000.0000.0000
0000.0000.0000

JetCore
No of Partner BPs

=
=

No
0

Partner BP2 MAC
Partner BP4 MAC
Partner BP6 MAC

=
=
=

0000.0000.0000
0000.0000.0000
0000.0000.0000

Server Load Balancing Debug Info
Total Get
=
3
Get Fails
=
0
Forward Sp
=
0
Bad creates
=
0
Fw resets
=
0
Double Free
=
0
Free inv Sess Idx
=
0
Cache-Reassigns
=
0
Multi Path Fwd Use
=
0
Bad non-owner
=
0
FTP-trans-error
=
0
Fw tcp inside move
=
0
Fw SYNC delayed
=
0
FW stale to conns
=
0
FW stale from conns =
0
FW stale from nuke c =
0

Total Free
Get Buffer failure
Reverse Sp
TCP Resets
Rev Resets
Error
Free list Idx inv
Trans-Denied
Multi Path Rev Use
Select Fwall
Cache track-error
Fw udp inside move
ownership contention
FW stale to delq con
FW stale from delq c
Sac frwds

=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=

0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0

Unxpectd udata
Client->Server
Drops
Fw_drops
FIN_or_RST
Disable_drop
Stale_drop
SYN def/proxy RST
Out of Memory
last conn rate
last TCP attack rate
fast vport found
Fwd to non-static FI

=
=
=
=
=
=
=
=
=
=
=
=
=

0
0
0
0
0
0
0
0
0
0
0
0
0

Unxpectd udata(def)
Server->Client
Aged
Rev_drops
old-conn
Exceed_drop
Unsuccessful
Server Resets
Out of Memory
max conn rate
max TCP attack rate
fast vport n found
Dup stale SYN

=
=
=
=
=
=
=
=
=
=
=
=
=

0
0
0
0
0
0
0
0
0
0
0
0
0

TCP forward FIN
Fast path FWD FIN
Fast path SLB SYN
Duplicate SYN
TCP ttl FIN recvd
Sessions in DEL_Q
Fwd sess not found
Sess rmvd from delQ
Fragment buf full er
New sess sync sent
L4 msg sent
foundry packet sent
TCP SYN received
TCP SYN to MP
TCP SYN ACK received
TCP pkt received
TCP pkt to MP

=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=

0 TCP reverse FIN
=
0
0 Fast path REV FIN
=
0
0 Dup SYN after FIN
=
0
0 Duplicate sessions
=
0
0 TCP ttl reset recvd =
0
0 Sess force deleted
=
0
0 sess already in delQ =
0
0
0 Incoming TCP cksum e =
0
0 New sess sync recvd =
0
0 L4 msg recvd
=
0
0 ipc packet sent
=
2818942
0 TCP SYN dropped
=
0
0 TCP SYN ACK to MP
=
0
0 TCP SYN ACK dropped =
0
0 TCP pkt dropped
=
0
0 PBSLB tftp status
= In progres

Avail. Sessions
Hash size

=
=

1999996
200001

Total Sessions

=

2000000

Total C->S Conn
=
0 Total S->C Conn
=
0
Total Reassign
=
0 Unsuccessful Conn
=
0
Server State - 0: diasbled, 1:enabled, 2:failed, 3:test, 4:suspect, 5:grace_dn, 6:active
Real Server

St CurrConn

TotConn

TotRevConn CurrSess

PeakConn

R1
rs1

1
1

0
0

0
0

0
0

0/0/0
0/0/0

0
0

No response to non-SYN first packet of a TCP flow
ServerIron can remain passive for non-SYN packet in the beginning of the flow. The default
behavior is to send TCP RESET to client when a non-SYN packet is received in the beginning.

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Prioritizing management traffic

1

By default, when ServerIron ADX receives TCP packet that is destined to VIP and there is no session
match then it sends TCP reset to the sender. However, if one desires to remain passive then the
above feature can be enabled.
To not send the reset packet, use the following command.
ServerIronADX(config)# server reset-on-syn-only

To remove the configuration, use the following command.
ServerIronADX(config)# no server reset-on-syn-only

Syntax: [no] server reset-on-syn-only

Prioritizing management traffic
ServerIron ADX software allows the system to prioritize traffic destined to the management IP
address in order to facilitate uninterrupted access to the ServerIron switch even under heavy load
conditions. This feature allows you to prioritize management traffic based on the following.
1. Client IP address/subnet
2. Protocol (TCP/UDP/IP) and
3. TCP or UDP port number
With this feature turned on, the specified traffic is directly forwarded to the Management Module in
hardware. In the following example, traffic from the source subnet 1.1.1.1 and destined to
management IP 10.45.16.104 for TCP port 22 (SSH) is prioritized.
ServerIronADX(config)# server prioritize-mgmt-traffic 1.1.1.1 255.255.255.0
10.45.16.104 6 22

Syntax: server prioritize-mgmt-traffic    [] []
The  variable specifies the Source IP address.
The  variable specifies the Mask for the source IP address.
The  variable specifies the Destination management IP address. The destination IP
address must already be configured on the ServerIron ADX. If the IP address is not configured, the
command is rejected.
The  variable specifies any protocol.
The  variable specifies a TCP or UDP port.
It is also possible to prioritize management traffic from any source ip as shown in the example
below.
ServerIronADX(config)# server prioritize-mgmt-traffic any 10.45.16.104 6 22

Syntax: [no] server prioritize-mgmt-traffic any  [] []

NOTE

The prioritizing management traffic feature should not be enabled for a ServerIron ADX router VE
address if this interface is used for source-NAT as that would break the SLB traffic flow.
Refer to the following examples.
Prioritization of TCP port 80 traffic to management IP 200.1.1.1

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Peak BP utilization with TRAP

ServerIronADX# server prioritize-mgmt-traffic 1.1.1.1 255.255.255.0 200.1.1.1 6
80

Prioritization of TCP port 80 traffic to management IP 200.1.1.1 from any source IP address
ServerIronADX# server prioritize-mgmt-traffic any 200.1.1.1 6 80

Prioritization of UDP port 2222 traffic to management IP 200.1.1.1
ServerIronADX# server prioritize-mgmt-traffic 1.1.1.1 255.255.255.0 200.1.1.1 17
2222

Prioritization of IP protocol 89 (OSPF) traffic to management IP 200.1.1.1
ServerIronADX# server prioritize-mgmt-traffic 1.1.1.1 255.255.255.0 200.1.1.1 89

Protection against attack in hardware
ServerIron ADX allows for protection against attack in hardware without impacting MP or BP CPU
utilization. Configure the server the drop-all-mgmt-access command to drop all traffic destined to a
specified management IP address.
The following command drops all traffic destined to the management IP address 10.45.16.104.
ServerIronADX(config)# server drop-all-mgmt-access 10.45.16.104

Syntax: [no] server drop-all-mgmt-access 

NOTE
For a router, the destination IP address is the physical or ve interface IP address For a switch, the
destination IP address is the management IP address.
The server drop-all-mgmt-access feature when used in combination with the server
prioritize-mgmt-traffic feature allows you to prioritize valid traffic while blocking unwanted traffic
destined to the management IP address.
For example, with the following configuration, only ssh, telnet and http traffic destined to
management IP address 10.45.16.104 will be prioritized and all other traffic destined to
10.45.16.104 will be dropped.
ServerIronADX(config)#server
10.45.16.104 6 22
ServerIronADX(config)#server
10.45.16.104 6 23
ServerIronADX(config)#server
10.45.16.104 6 80
ServerIronADX(config)#server

prioritize-mgmt-traffic 1.1.1.1 255.255.255.0
prioritize-mgmt-traffic 1.1.1.1 255.255.255.0
prioritize-mgmt-traffic 1.1.1.1 255.255.255.0
drop-all-mgmt-access 10.45.16.104

Peak BP utilization with TRAP
Show CPU-utilization command enhancement
The show cpu-utilization command displays CPU utilization peaks since the system boot or the last
reset of counters (using the clear cpu utilization command).
The command, clear cpu-utilization, on both the MP and the BP is used to reset the counter.

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1

BP utilization threshold
The bp-utilization-threshold command allows you to specify a threshold for BP CPU utilization.
Define this command under the global configuration mode.
When the threshold is exceeded, the event is logged and a trap is sent. The log and trap are
rate-limited to one per two minutes.
The command takes a percentage string as parameter.
Example
ServerIronADX(config)# bp-utilization-threshold 80.5%

Syntax: bp-utilization-threshold 

MP utilization threshold
The mp-utilization-threshold command specifies a threshold for BP CPU utilization. Define this
command under the global configuration mode.
When the threshold is exceeded, the event is logged and a trap is sent. The log and trap are
rate-limited to one every two minutes.
The command takes a percentage string as parameter.
Example
ServerIronADX(config)# mp-utilization-threshold 80.5%

Syntax: mp-utilization-threshold 

Transaction Rate Limit (TRL)
Transaction Rate Limit, allows the ServerIron ADX to monitor and limit traffic from any one IP
address.

Understanding transaction rate limit
Transaction Rate Limit counts the number of transactions received from any one IP address. If the
transaction count exceeds a specified threshold value, traffic from that IP address is held and not
processed for a specified number of minutes.
Transaction rate limit provides the flexibility to specify different configurations for different clients,
based on the client IP address/prefix.
Transaction rate limit provides the following benefits:

• Ability to apply a default transaction rate limit value to all clients, while maintaining an
exception list.

• Ability to apply a different transaction rate limit rate per client IP or prefix.
• Ability to exclude specific IP addresses or prefixes from transaction rate limit and maintain an
exclude list.

• Ability to apply transaction rate limit to traffic coming to a specific VIP only.

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Transaction Rate Limit (TRL)

• Ability to operate on a per VIP basis, whereby a different rate limit can be applied to traffic
coming to a different VIP.

Configuring transaction rate limit
To enable transaction rate limit, you must configure parameters for each client address/prefix and
apply the transaction rate limit configuration to a specific VIP.

Prerequisites
Before you can configure transaction rate limit, you must configure a virtual server. The following
example shows how to configure a virtual server.
ServerIronADX> enable
ServerIronADX# config terminal
ServerIronADX(config)# server virtual-name-or-ip bwVIP 1.1.1.33

Syntax: [no] server virtual-name-or-ip  

Configure transaction rate limit rule set
The transaction rate limit parameters are grouped into a set and each set is associated with a
name. To create a set of transaction rate limit rules, follow these steps.
1. Enable privileged EXEC mode.
ServerIronADX> enable

2. Enter global configuration mode.
ServerIronADX# configure terminal

3. Configure name of a transaction rate limit rule set and enter client transaction rate limit
configuration mode.
ServerIronADX(config)#client-trans-rate-limit tcp TRL1

Syntax: [no] client-trans-rate-limit tcp | udp | icmp 
4. Specify the trl keyword for client subnet and set connection rate.
For IPv4:
ServerIronADX(config-client-trl-trl1)# trl 100.1.1.0 255.255.255.0
monitor-interval 3 conn-rate 10 hold-down-time 1

For IPv6:
ServerIronADX(config-client-trl-trl1)# trl 100::1/128 monitor-interval 3
conn-rate 10 hold-down-time 1

Syntax: [no] trl {   |   } monitor-interval
 conn-rate  hold-down-time 

Configure transaction rate limit to exclude a client
You can configure a client address/prefix to be excluded from transaction rate limiting within a
transaction rate limit configuration group.
To exclude a client from transaction rate limit, follow these steps.

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1

1. Enable privileged EXEC mode.
ServerIronADX> enable

2. Enter global configuration mode.
ServerIronADX# configure terminal

3. Specify the name of the transaction rate limit rule set and enter client transaction rate limit
configuration mode.
ServerIronADX(config)# client-trans-rate-limit tcp TRL1

Syntax: [no] client-trans-rate-limit tcp | udp | icmp 
4. Specify the trl parameter for the client subnet and the exclude keyword.
For IPv4:
ServerIronADX(config-client-trl-TRL1)# trl 100.1.1.0 255.255.255.0 exclude

For IPv6:
ServerIronADX(config-client-trl-TRL1)# trl 300::1/128 exclude

Syntax: [no] trl {   |   } exclude

Configure a transaction rate limit default
You can specify a default transaction rate limit configuration for all other clients that are not
explicitly configured. To create a transaction rate limit default for a group, follow these steps.
1. Enable privileged EXEC mode.
ServerIronADX> enable

2. Enter global configuration mode.
ServerIronADX# configure terminal

3. Specify name of transaction rate limit rule set and enter client transaction rate limit
configuration mode.
ServerIronADX(config)# client-trans-rate-limit tcp TRL1

Syntax: [no] client-trans-rate-limit tcp | udp | icmp 
4. Specify the default trl parameter for this group.
ServerIronADX(config-client-trl)# trl default monitor-interval 3 conn-rate 10
hold-down-time 1

Syntax: [no] trl default monitor-interval  conn-rate  hold-down-time


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Configure transaction rate limit for pass through traffic
You can configure transaction rate limit for traffic that is not going to a virtual server. You can
configure only one group for pass through traffic.
To create a transaction rate limit group for pass through traffic, follow these steps.
1.

Enable privileged EXEC mode.
ServerIronADX> enable

2. Enter global configuration mode.
ServerIronADX# configure terminal

3. Specify name of BW rule set and enter client bandwidth configuration mode.
ServerIronADX(config)# client-trans-rate-limit tcp default

Syntax: [no] client-trans-rate-limit tcp | udp | icmp default
4. Specify the trl parameter for the client subnet and set a connection rate.
For IPv4:
ServerIronADX(config-client-trl)#trl 100.1.1.0 255.255.255.0 monitor-interval
3 conn-rate 10 hold-down-time 1

For IPv6:
ServerIronADX(config-client-trl)#trl 300:11/128 monitor-interval 3 conn-rate
10 hold-down-time 1

Syntax: [no] trl {   |   } monitor-interval
 conn-rate  hold-down-time 
5. The transaction rate limit policy pertaining to the protocol and the port must be applied to
either the physical or the virtual interface for pass through traffic. This will ensure that the
traffic is brought to the application processor (BP) for rate-limitation.
Applying policy on physical interface
ServerIronADX(config) # interface eth 1/1
ServerIronADX(config-if-1/1) # ip tcp trans-rate 80

Applying policy on virtual interface
ServerIronADX(config) # interface ve 20
ServerIronADX(config-vif-20) # ip udp trans-rate 53

Syntax: [no} ip tcp | udp trans-rate 
Syntax: [no} ip icmp trans-rate
The  parameter specifies one or more TCP or UDP ports to monitor. You can monitor up
to four ports.

Apply transaction rate limit to a VIP
After configuring transaction rate limit, you must bind transaction rate limit to a VIP. To enable
transaction rate limit, follow these steps.
1. Enable privileged EXEC mode.
ServerIronADX> enable

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2. Enter global configuration mode.
ServerIronADX# configure terminal

3. Specify server virtual-name-or-ip command and VIP name to enter virtual server configuration
mode.
ServerIronADX(config)# server virtual-name-or-ip bwVIP

Syntax: [no] server virtual-name-or-ip 
4. Specify the BW parameter and BW rule set.
ServerIronADX(config-vs-bwVIP)# client-trans-rate-limit trl

Syntax: [no] client-trans-rate-limit 
5. The transaction rate limit policy pertaining to the protocol and the port must be applied to
either the physical or the virtual interface for traffic hitting to Virtual IP.
Applying policy on physical interface
ServerIronADX(config) # interface eth 1/1
ServerIronADX(config-if-1/1) # ip tcp trans-rate 80

Applying policy on virtual interface
ServerIronADX(config) # interface ve 20
ServerIronADX(config-vif-20) # ip udp trans-rate 53

Syntax: [no} ip tcp | udp trans-rate 
Syntax: [no} ip icmp trans-rate
The  parameter specifies one or more TCP or UDP ports to monitor. You can monitor up
to four ports.

Deleting all TRL rules in a policy
You can delete all TRL rules in a policy as shown.
ServerIronADX(config)# client-trans-rate-limit tcp trl1
ServerIronADX(config-client-trl-trl1)# trl delete-all-rules

Syntax: trl delete-all-rules

Download transaction rate limit configuration from a TFTP server. (optional)
When a Transaction Rate Limit configuration becomes very large, you can download the
configuration from a TFTP server.

NOTE

A TRL configuration file can have IPv4 as well as IPv6 rules.
The following example shows how to download a Transaction Rate Limit configuration from a TFTP
server.
ServerIronADX(config)# server trl tftp 100.1.1.1 test.trl 2

Syntax: server trl tftp   
Specify the following values.

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 —IP address of the TFTP server.
 —File name of Transaction Rate Limit configuration.
 —Retry number for the download.
Verify that the Transaction Rate Limit configuration file is in the following format.
client-trans-rate-limit tcp trl101
trl 10.2.24.0/24 monitor-interval 50 conn-rate 100 hold-down-time 60
trl 10.2.24.10/32 exclude

NOTE

This is the same format as the show running-configuration command generates.

Configuring the maximum number of rules
By default a TRL a policy can have up to 2500 IPv4 rules and 2500 IPv6 rules. A maximum of
15,000 IPv4 and 15,000 IPv6 rules are supported on a ServerIron ADX for all policies. While the
maximum number of rules cannot be increased over the 15,000 maximum, these limits can be
changed globally or locally per-policy.

Changing the maximum number of rules globally.
You can change the maximum number of TRL rules globally on a ServerIron ADX for all policies as
shown.
ServerIronADX(config)# client-trans-rate-limit max-ipv4-rules 2000

Syntax: [no] client-trans-rate-limit { max-ipv4-rules | max-ipv6-rules } 
The max-ipv4-rules parameter specifies that the rules limit is being set for IPv4 rules.
The max-ipv6-rules parameter specifies that the rules limit is being set for IPv6 rules.
The  variable specifies the number of rules that will be supported globally. The
maximum values (also the default) are: 15,000 for IPv4 and 15,000 for IPv6.

Changing the maximum number of rules locally per-policy.
You can change the maximum number of TRL rules for an individual policy on a ServerIron ADX for
as shown.
ServerIronADX(config)# client-trans-rate-limit tcp trl1
ServerIronADX(config-client-trl-trl1)# trl max-ipv4-rules 2000

Syntax: [no] trl { max-ipv4-rules | max-ipv6-rules } 
The max-ipv4-rules parameter specifies that the rules limit is being set for IPv4 rules for the
specified policy.
The max-ipv6-rules parameter specifies that the rules limit is being set for IPv6 rules for the
specified policy.
The  variable specifies the number of rules that will be supported for the specified
policy that this command is being configured under. The default values are: 2500 for IPv4 and
2500 for IPv6. The value for each (IPv4 and IPv6) can be set to any number as long as the global
limits are observed.

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Saving a TRL configuration
The following applies to saving a TRL config:

• the startup-config cannot store 15,000 IPv4 and 15,000 IPv6 rules.
• If the total number of IPv4 and IPv6 rules exceeds 2500, issuing the write mem command
stores the TRL rules in the “trl_conf.txt” file on the internal USB drive.

• the policy config and global/local maximum rule count config is always stored in the
startup-config.

Disabling the storage of TRL rules on the internal USB drive
By default, storage of TRL rules on the internal USB drive of a ServerIron ADX is enabled. You can
disable the storage of TRL rules on the internal USB drive of a ServerIron ADX as shown.
ServerIronADX(config)# no client-trans-rate-limit usb-config-gen

Syntax: no client-trans-rate-limit usb-config-gen

NOTE

Where the storage of TRL rules on the internal USB drive of a ServerIron ADX is disabled and the
total rules exceeds 2500, only 2500 rules would be saved in startup-config.

Transaction rate limit command reference
This section describes the syntax, semantics, and usage for each transaction rate limit command.
This section contains the following sections:

• “client-trans-rate-limit”
• “trl”

client-trans-rate-limit
Use the client-trans-rate-limit command in the global configuration mode to configure a transaction
rate limit rule name and traffic type.
Syntax: client-trans-rate-limit {icmp  | default} | {tcp  | default} |
{udp  | default}
icmp - Specifies ICMP transaction rate limit for client subnet.
tcp - Specifies TCP transaction rate limit for client subnet.
udp - Specifies UDP transaction rate limit for client subnet.
 - Specifies the name for this configuration.
default - Specifies default.

trl
Use the trl command in the global configuration client-trl mode to configure transaction rate limit
rules.

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Syntax: trl {default | {   |   } {exclude |
monitor-interval
 conn-rate  hold-down-time }}
default - Specifies default transaction rate limit parameter.
 - Specifies IPv4 client subnet and  - Specifies the IPv4 client mask.
 - Specifies IPv6 client subnet and  - Specifies the IPv6 client mask bits.
exclude - Specifies to exclude the prefix from transaction rate limit.
monitor-interval - Specifies time interval for monitoring in 100ms.
 - Specifies value of time interval for monitoring.
conn-rate - Specifies connection rate.
 - Specifies value of connection rate for client.
hold-down-time - Specifies time for holding down source.
 - Specifies hold down time in minutes.
Command modes
Global configuration mode.

Global TRL
If TRL per client subnet is not needed, Global TRL can be used to create a configuration to apply to
all the incoming traffic.
Use ip [tcp | udp | icmp] trans-rate to enable TRL on the ServerIron for TCP, UDP, or ICMP traffic. If
any more than a specified number packets per second come from the same IP address over a
specified interval, then all traffic from that IP address is held down for a specified number of
minutes.
Syntax: [no] ip [tcp | udp | icmp] trans-rate monitor-interval  conn-rate 
hold-down-time 
monitor-interval  Amount of time used to measure incoming traffic. This parameter is
specified in increments of 100ms. For example, to measure traffic over a 1 second interval, you
would specify 10 for this.
conn-rate  Threshold for the number of connections per second from any one IP address.
Traffic exceeding this rate over the specified interval is subject to hold down.
hold-down-time  Number of minutes that traffic from an IP address that has sent
packets at rate higher than the configured threshold is to be held down.
Example
ServerIronADX(config)# ip tcp trans-rate monitor-interval 600 conn-rate 100
hold-down-time 5

This command configures the ServerIron to monitor incoming TCP traffic. If more than 100 TCP
connections per second arrive from the same IP address over a 60-second interval (600 X 100ms),
then all TCP traffic from that IP address is held down for 5 minutes.
To apply TRL to TCP traffic coming into port 80 on interface 1/1.

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ServerIronADX(config)# interface ethernet 1/1
ServerIronADX(config-if-1/1)# ip tcp trans-rate 80

where  sets one or more TCP or UDP ports to monitor. With TRL, the ServerIron can monitor
up to 4 specific ports. The ServerIron can also monitor traffic to all the ports by configuring the
default port.

TRL plus security ACL-ID
Even though TRL is applied to an interface and effects all traffic received on this interface, with the
security acl-id  command TRL can be applied only to specific traffic coming in on that
interface.Refer to “security acl-id” on page 15.

security acl-id
The security global command accepts acl-id  as a parameter.
Syntax: [no] security acl-id 
Example
ServerIronADX(config)# security acl-id 4

Once security acl-id  is configured, only packets matching the configured ACL will be
subject to the L4 security rules configured on the system. (Specifically, TRL and manual hold down
will take effect only for packets matching this configured ACL). If you want specific traffic to bypass
the L4 security features, then do not include those IP addresses in the access list.

NOTE
The security acl-id takes precedence over all TRL configuration.

Transaction rate limit hold-down value
if you configure "hold down 0," the incoming request is not held down. Instead it generates a log.

Displaying TRL rules statistics
You can display statistics for TRL rules as shown.
ServerIronADX#show client-trl rules-stat
Policy-Name default-rule ipv4-rules-alloted ipv4-rules-added
trl1
0
2500
0
trl2
0
2500
0
trl3
0
2500
0
Global ipv4 rule num: 2500, total-alloted-ipv4-rules: 7500
Global ipv6 rule num: 2500, total-alloted-ipv6-rules: 7500

ipv6-rules-alloted
2500
2500
2500

ipv6-rules-added
0
0
0

Syntax: show client-trl rules-stat

Displaying TRL rules in a policy
You can display TRL rules in a policy as shown.

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ServerIronADX#show client-trl trl-policy1 ipv6 40
Max Count: 2500
Total Count: 2
IP address/Mask
--------------300::3a95/128
300::3a96/128

interval
-------1
66

attempts
-------67
38

holddown
-------93
34

Syntax: show client-trl  { ipv4 | ipv6} 
The  variable specifies the TRL policy that you want to display rules for.
The show client-trl command displays entries in the TRL policy list, starting from the point specified
with the  parameter.

Displaying IP address with held down traffic
To display a list of IPv4 and IPv6 addresses whose traffic has been held down, enter commands
such as the following.
ServerIronADX# rconsole 2 1
ServerIronADX2/1 #show security holddown
source
192.168.2.30
192.168.2.40

destination
Any tcp
Any tcp

vers attempt start
0
000ab6ae
0
000ab6ea

last
HD time
00000000 Y 9
00000000 Y 9

Syntax: rconsole  
Syntax: show security holddown
The following table lists the output from the show security holddown command.

TABLE 1

Output from the show security holddown command

Field

Description

source

Source IPv4 or IPv6 address that is currently being held down

destination

TCP, UDP, or ICMP depending on the type of traffic sent by the client.

vers

Used by Brocade Technical Support.

attempt

Number of connection attempts made by the client during the current monitoring interval.

start

Time stamp representing the start of the monitoring interval.

last

Time stamp representing the last time the ServerIron received a connection request from
the client.

HD

Whether the IP address is currently being held down. Y indicates that the address is being
held down. N indicates that it is not.

time

Time remaining for this IP address to be held down, if the HD field contains Y.

Refusing new connections from a specified IP address
Use the security hold-source-ip command to refuse new connections from a specified IP address
for a specified amount of time. This feature applies to all TCP, UDP, and ICMP traffic originating
from the specified IP address.
Syntax: [no] security hold-source-ip  

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Example

To configure the ServerIron to refuse connections from 192.168.9.210 for 20 minutes, enter.
ServerIronADX(config)# security hold-source-ip 192.168.9.210 20

To display the IP addresses from which connections are currently being refused.
ServerIronADX# rconsole 2 1
ServerIronADX2/1 # show security holddown
source
192.168.2.30
192.168.2.40

destination
Any tcp
Any tcp

vers attempt start
0
000ab6ae
0
000ab6ea

last
HD time
00000000 Y 9
00000000 Y 9

The IP addresses for which connections are being refused are displayed in the source column.

HTTP TRL
This section describes how to use the HTTP Transaction Rate Limiting (TRL) feature with ServerIron
devices.

Overview of HTTP TRL
HTTP TRL provides HTTP transaction rate limiting for SSL and HTTP traffic, based on a customer ID.
Existing ServerIron TRL features, which are based on source IP addresses, are inadequate in
environments where a client is identified by an application user ID. HTTP TRL allows you to prevent
per-client over subscription by allowing you to configure features, such as transaction and
connection rate limiting, based on customer IDs.
With HTTP TRL, the rate limit configuration for each customer is grouped into a set. Each of these
groups can be applied to multiple VIPs. A counter is maintained on per-VIP basis. When a client
request is received, the client customer ID is extracted and decoded. A table lookup is performed
on the customer ID and, if the client is subjected to a rate limit, a session lookup is done to locate
the current connection information.
For each BP, the current counter is checked against the configuration. If the limit is exceeded, the
configured action occurs.

HTTP TRL features
Before you configure HTTP TRL, you should be aware of the following benefits and restrictions for
this feature:

• The customer ID is contained within the HTTP header, is alphanumeric, and can be up to 101
characters in length.

• Maximum customer ID entries is 35K.
• Customer ID entries can be manually configured or have dynamic upload support.
• All customer connections are supported on a single VIP with support for up to 10K
connections.

• Customer report response times can run up to 120 seconds before they timeout at the
gateway tier.

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• Rate-limiting functionality must support rate over time and total connections, based on
customer ID.

• Max-conn currently works only for HTTP1.0.
• This feature supports http redirect, or drop client response actions once rate-limit has been
exceeded.

• This feature provides event and threshold alert monitoring and notification, based on specific
customer connection SLAs.

Configuring HTTP TRL
This section describes how to configure the HTTP TRL feature.

NOTE

For traffic going through a VIP, Brocade recommends that you apply the TRL policy to the VIP and
Interface.

Configuring HTTP TRL client
Use the following procedures to configure the HTTP TRL client rate limit and the client maximum
connection.

Configuring HTTP TRL client rate limit
To configure the HTTP TRL client rate limit, follow these steps.
1. Define an HTTP TRL policy.
ServerIronADX(config)# http-trl-policy p1

Syntax: [no] http-trl-policy 
2. Configure an HTTP TRL client rate limit.
ServerIronADX(config-http-trl-p1)# client-name c1 monitor-interval 1 10 20 0

Syntax: [no] client-name  monitor-interval  
 
For more detailed command information, refer to “Client-name 
monitor-interval” on page 27.
3. Configure the action to take if a client exceeds the configured rate limit (optional).
ServerIronADX(config-http-trl-p1)# client-name c1 exceed-action reset

Syntax: [no] client-name  exceed-action reset

Configuring HTTP TRL client maximum connection
To configure HTTP TRL client maximum connection, follow these steps.
1. Define an HTTP TRL policy.
ServerIronADX(config)# http-trl-policy p1

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Syntax: [no] http-trl-policy 
2. Configure an HTTP TRL client maximum connection.
ServerIronADX(config-http-trl-p1)# client-name c1 max-conn 10

Syntax: [no] client-name  max-conn 
—specifies maximum number of connection client can setup.
3. Configure the action to take if a client exceeds the configured maximum connections
(optional).
ServerIronADX(config-http-trl-p1)# client-name c1 exceed-action reset

Syntax: [no] client-name  exceed-action reset

Configuring HTTP TRL defaults
Use the following procedures to configure the HTTP TRL default rate limit and the default maximum
connection.

Configuring HTTP TRL default rate limit
To configure HTTP TRL default rate limit, follow these steps.
1. Define an HTTP TRL policy.
ServerIronADX(config)# http-trl-policy p1

Syntax: [no] http-trl-policy 
2. Configure an HTTP TRL default rate limit.
ServerIronADX(config-http-trl-p1)# default monitor-interval 1 10 20 0

Syntax: [no] default monitor-interval   

3. Configure the action to take if a client exceeds the configured rate limit (optional).
ServerIronADX(config-http-trl-p1)# default exceed-action reset

Syntax: [no] default exceed-action reset

Configuring HTTP TRL default maximum connection
To configure HTTP TRL default maximum connection, follow these steps.
1. Define an HTTP TRL policy.
ServerIronADX(config)# http-trl-policy p1

Syntax: [no] http-trl-policy 
2. Configure an HTTP TRL default maximum connection.
ServerIronADX(config-http-trl-p1)# default max-conn 10

Syntax: [no] default max-conn 
3. Configure the action to take if a client exceeds the configured maximum connection (optional).
ServerIronADX(config-http-trl-p1)# default exceed-action reset

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Syntax: [no] default exceed-action reset

Sample HTTP TRL configuration
This section describes how to configure a sample HTTP TRL configuration. This scenario describes
all the required steps for configuring HTTP TRL, with notes the optional steps. This configuration
consists of four parts:

•
•
•
•

Creating an HTTP TRL policy with a client rate limit
Configuring Layer 4 server load balancing
Creating a CSW rule and policy with HTTP TRL
Enabling Layer 7 server load balancing

Creating an HTTP TRL policy with client rate limit
To configure a HTTP TRL policy with client rate limit, follow these steps.
1. Define an HTTP TRL policy.
ServerIronADX(config)# http-trl-policy p1

Syntax: [no] http-trl-policy 
2. Configure an HTTP TRL client rate limit.
ServerIronADX(config-http-trl-p1)# client-name c1 monitor-interval 1 10 20 0

Syntax: [no] client-name  monitor-interval  
 
3. Configure the action to take if a client exceeds the configured rate limit (optional).
ServerIronADX(config-http-trl-p1)# client-name c1 exceed-action reset

Syntax: [no] client-name  exceed-action reset

Configuring Layer 4 SLB
To configure Layer 4 SLB, follow these steps.
1.

Define a real server (1) with an IP address.
ServerIronADX(config)# server real web1 1.1.1.1

Syntax: server real  
2. Define a real HTTP port on the real server.
ServerIronADX(config-rs-web1)# port http

Syntax: port http
3. Define a real server (2) with an IP address.
ServerIronADX(config-rs-web1)# server real web2 1.1.1.2

Syntax: server real  
4. Define a real HTTP port on the real server and exit.
ServerIronADX(config-rs-web2)# port http

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Syntax: port http
ServerIronADX(config-rs-web2)# exit

Syntax: exit
5. Define a virtual server with an IP address.
ServerIronADX(config)# server virtual-name-or-ip csw-vip 1.1.1.100

Syntax: server virtual-name-or-ip  
6. Define a virtual HTTP port on the virtual server.
ServerIronADX(config-vs-csw-vip)#port http

Syntax: port http
7.

Bind HTTP ports on real servers web1 and web2 to the virtual port HTTP.
ServerIronADX(config-vs-csw-vip)# bind http web1 http web2 http

Syntax: bind http  http 

Creating a CSW rule and policy with HTTP TRL
1. Define a CSW rule to match a pattern in the HTTP header that contains the client name.
ServerIronADX(config)# csw-rule rule1 header Authorization pattern Basic

Syntax: csw-rule  header  pattern 
2. Define a CSW policy.
ServerIronADX(config)# csw-policy policy1

Syntax: csw-policy 
3. Specify an action to apply HTTP TRL policy when the CSW rule is matched.
ServerIronADX(config-csw-policy1)# match rule1 http-trl p1

Syntax: match  http-trl 

Enabling Layer 7 SLB
To configure Layer 7 SLB, follow these steps.
1. Bind the policy to a virtual HTTP port on the virtual server.
ServerIronADX(config-vs-csw-vip)# port http csw-policy policy1

Syntax: port http csw-policy 
2. Enable CSW on the virtual port.
ServerIronADX(config-vs-csw-vip)# port http csw

Syntax: port http csw

Displaying HTTP TRL
This section describes how to display HTTP TRL information.

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Display all HTTP TRL policies
To show all running configurations for HTTP TRL policies, use the following command.
ServerIronADX# show run http-trl-policy all

Syntax: show run http-trl-policy all
Example
ServerIronADX# show run http-trl all
!Building configuration...
!Current configuration : 124813 bytes
!
http-trl-policy "my-http-trl-policy-104"
tftp 50.50.50.105 "http-trl-policy-104.txt"
client-name "root1" max-conn 1
client-name "root1" exceed-action reset
client-name "root10" max-conn 1
client-name "root10" exceed-action reset
client-name "root11" max-conn 1
client-name "root11" exceed-action reset
client-name "root12" max-conn 1
client-name "root12" exceed-action reset
client-name "root13" max-conn 1
client-name "root13" exceed-action reset
client-name "root14" max-conn 1
client-name "root14" exceed-action reset
client-name "root15" max-conn 1
client-name "root15" exceed-action reset
client-name "root16" max-conn 1
client-name "root16" exceed-action reset
client-name "root17" max-conn 1
client-name "root17" exceed-action reset...

Display HTTP TRL policy from index
To show a running configuration for an HTTP TRL policy starting from an index, enter the following
command.
ServerIronADX# show run http-trl-policy my-http-trl-policy-104 2

Syntax: show run http-trl-policy  
Example
ServerIronADX# show run http-trl my-http-trl-policy-104 2
!Building configuration...
!Current configuration : 4261 bytes
client-name "root11" max-conn 1
client-name "root11" exceed-action reset
client-name "root12" max-conn 1
client-name "root12" exceed-action reset
client-name "root13" max-conn 1
client-name "root13" exceed-action reset
client-name "root14" max-conn 1
client-name "root14" exceed-action reset
client-name "root15" max-conn 1
client-name "root15" exceed-action reset
client-name "root16" max-conn 1
client-name "root16" exceed-action reset

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client-name
client-name
client-name
client-name
client-name
client-name
client-name
client-name
client-name

1

"root17" max-conn 1
"root17" exceed-action reset
"root18" max-conn 1
"root18" exceed-action reset
"root19" max-conn 1
"root19" exceed-action reset
"root2" max-conn 1
"root2" exceed-action reset
"root20" max-conn 1...

Display HTTP TRL policy client
To show a running configuration for an HTTP TRL policy client, enter the following command.
ServerIronADX# show run http-trl-policy my-http-trl-policy-104 root1

Syntax: show run http-trl-policy  
Example
ServerIronADX#show run http-trl my-http-trl-policy-104 root1
!Building configuration...
!Current configuration : 75 bytes
client-name "root1" max-conn 1
client-name "root1" exceed-action reset

Display HTTP TRL policy starting from index
To show a running configuration for an HTTP TRL policy starting from index for a specific number of
entries, enter the following command.
ServerIronADX# show run http-trl-policy my-http-trl-policy-104 1 20

Syntax: show run http-trl-policy   
Example
ServerIronADX# show run http-trl my-http-trl-policy-104 1 20
!Building configuration...
!Current configuration : 1500 bytes
client-name "root10" max-conn 1
client-name "root10" exceed-action reset
client-name "root11" max-conn 1
client-name "root11" exceed-action reset
client-name "root12" max-conn 1
client-name "root12" exceed-action reset
client-name "root13" max-conn 1
client-name "root13" exceed-action reset
client-name "root14" max-conn 1
client-name "root14" exceed-action reset
client-name "root15" max-conn 1
client-name "root15" exceed-action reset
client-name "root16" max-conn 1
client-name "root16" exceed-action reset
client-name "root17" max-conn 1
client-name "root17" exceed-action reset
client-name "root18" max-conn 1

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Displaying HTTP TRL

client-name
client-name
client-name
client-name

"root18" exceed-action reset
"root19" max-conn 1
"root19" exceed-action reset
"root2" max-conn 1...

Display HTTP TRL policy matching a regular expression
To show a running configuration for an HTTP TRL policy matching a specific regular expression
(regex), enter the following command.

NOTE
The syntax for regex is the same as for piping.
ServerIronADX# show run http-trl-policy my-http-trl-policy-109 regex ot1

Syntax: show run http-trl-policy  regex < regular expression>
Example
ServerIronADX#show run http-trl my-http-trl-policy-104 regex ot1
!Building configuration...
!Current configuration : 825 bytes
client-name "root1" max-conn 1
client-name "root1" exceed-action reset
client-name "root10" max-conn 1
client-name "root10" exceed-action reset
client-name "root11" max-conn 1
client-name "root11" exceed-action reset
client-name "root12" max-conn 1
client-name "root12" exceed-action reset
client-name "root13" max-conn 1
client-name "root13" exceed-action reset
client-name "root14" max-conn 1
client-name "root14" exceed-action reset
client-name "root15" max-conn 1
client-name "root15" exceed-action reset
client-name "root16" max-conn 1
client-name "root16" exceed-action reset
client-name "root17" max-conn 1
client-name "root17" exceed-action reset
client-name "root18" max-conn 1
client-name "root18" exceed-action reset
client-name "root19" max-conn 1...

Display HTTP TRL policy client index (MP)
To show an HTTP TRL policy client with a starting and ending index, enter the following command
on the MP.
ServerIronADX# show http-trl policy my-http-trl-policy-103 0 10

Syntax: show http-trl policy   

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Example
ServerIronADX# show http-trl policy my-http-trl-policy-103 0 10
Policy Name:
my-http-trl-policy-103
configured client count: 1
total client count: 1
Client name TDSWS/LoadRunner
monitor-interval 1
warning rate 10
shutdown rate 20
holddown interval 0
exceed action: drop
dynamic No
max-conn track session 0
trl track session 0

Syntax: show http-trl policy   

NOTE

This command entered on the MP only displays configuration information and total entry count for
this policy. The same command entered on the BP provides traffic status.

Display HTTP TRL policy client index (BP)
To show HTTP TRL policy client with a starting and ending index, use the following command on the
BP.
ServerIronADX# show http-trl policy my-http-trl-policy-103 0 10

Syntax: show http-trl policy   

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Downloading an HTTP TRL policy through TFTP

Example
ServerIronADX# show http-trl policy my-http-trl-policy-103 0 100
Policy Name:
my-http-trl-policy-103
configured client count: 1
total client count: 2
Client name V E'Vææ\
max-conn 50
dynamic Yes
max-conn track session 1
trl track session 0
HTTP_TRL_HIT
3278
HTTP_TRL_PASS
1613
HTTP_MAX_CONN_F 1665
HTTP_TRL_DROP
1665
Client name TDSWS/LoadRunner
monitor-interval 1
warning rate 10
shutdown rate 20
holddown interval 0
exceed action: drop
dynamic No
max-conn track session 0
trl track session 1
HTTP_TRL_HIT
66352
HTTP_TRL_PASS
39524
HTTP_TRL_FAIL
26828
HTTP_TRL_DROP
26828
ServerIronADX2/1#
ServerIronADX2/1# sh http-trl session 90.90.90.103 80 my-http-trl-policy-103
HTTP-MAX: V E'Vææ\ config 50, current 50
HTTP-TRL: TDSWS/LoadRunner, config 2, attamp 3, hold 0, 1st 3089554, last 3092565

Display HTTP TRL policy for all client entries (BP)
To display HTTP TRL policy information for all client entries, enter the following command on the BP.
ServerIronADX2/1# show http-trl resource

Example
ServerIronADX2/1# show http-trl resource
Maximum client entry: 35000
Free client entry: 0
Total allocated client entry: 35000
Total freed client entry: 0
Maximum allocated client entry: 35000
Maximum client entry: 35000
Double free client entry: 0
Invalid free client entry: 0
Failed allocate client entry: 0
Double allocated client entry: 0

Downloading an HTTP TRL policy through TFTP
To download an HTTP TRL policy using TFTP, enter a command similar to the following.
ServerIronADX(config-http-trl-p1)# tftp 100.1.1.1 http-trl-config.txt

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Syntax: tftp  

NOTE

You can save this command with write memory to automatically initiate a download for this policy
after you reload. If you configure more than one policy for TFTP download, and a policy fails the
download, the ServerIron does NOT retry, and the subsequent policy does not initiate a download.
You must manually issue the command to do a TFTP download.

NOTE

When the total number of HTTP TRL entries exceeds 10k, the show run time config command cannot
display an http trl-related configuration. You must use a text file to manage it.

NOTE
When any HTTP TRL policy client entry exceeds 1K, the show run time config command cannot
display a detailed client entry for the HTTP TRL policy.

HTTP TRL policy commands
NOTE

You must configure client HTTP TRL before you configure the client exceed-limit

Client-name  monitor-interval
Use the client-name  monitor-interval option in the http-trl-policy configuration mode
to set client rate limiting parameters.
Syntax: [no] client-name  monitor-interval  
 
—specifies monitoring window in 100 ms unit.
—specifies HTTP connection rate (per second) that causes a warning if exceeded.
—specifies HTTP connection rate (per second) that causes a client to hold down.
—specifies the length of hold down period, if client exceeds rate limit in term of
minutes.

NOTE

Value 0 means do not hold down. Hold down holds all traffic.
Example
ServerIronADX(config-http-trl-p1)# client-name c1 monitor-interval 1 10 20 0

Client-name  max-conn
Use the client-name  max-conn option in the http-trl-policy configuration mode to set
client maximum connection parameters.
Syntax: [no] client-name  max-conn 

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HTTP TRL policy commands

—specifies maximum number of connections client can setup.
Example
ServerIronADX(config-http-trl-p1)# client-name c1 max-conn 10

NOTE
You must set the client HTTP max-conn configuration before you configure the client exceed-action.

NOTE

Max-conn currently supports only HTTP/1.0.

Client-name  exceed-action
Use the client-name  exceed-action option in the http-trl-policy configuration mode to
set the action to take if a client exceeds the configured rate limit,.
Syntax: [no] client-name  exceed-action [reset | drop]
[reset | drop] specifies client request be reset or dropped if exceeds limit.
Example
ServerIronADX(config-http-trl-p1)# client-name c1 exceed-action [reset]

Syntax: [no] client-name  exceed-action redirect   [port]
 and —specifies client request to be redirected to this new URL, if limit is exceeded.

NOTE
Use an asterisk (*) to keep the same domain or url. This does not apply if the client is using HTTP 1.0.
ServerIronADX(config-http-trl-p1)# client-name c1 exceed-action redirect * /new
exceed.html http

NOTE
The same domain is used in the incoming packet.
The optional [port] specifies the new TCP port number for the redirected URL.
ServerIronADX(config-http-trl-p1)# client-name c1 exceed-action redirect
www.yahoo.com exceed.html http

Default monitor-interval
Use the default monitor-interval option in the http-trl-policy configuration mode to set default rate
limiting parameters.
Syntax: [no] default monitor-interval   


• —specifies monitoring window in 100 ms unit.
• —specifies HTTP connection rate (per second) that causes a warning if
exceeded.

• —specifies HTTP connection rate (per second) that causes a client to hold
down.

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• —specifies the length of hold down period, if client exceeds rate limit in
term of minutes.

NOTE

Value 0 means do not hold down. Hold down holds all traffic.
Example
ServerIronADX(config-http-trl-p1)# default monitor-interval 1 10 20 0

Default max-conn
Use the default max-conn option in the http-trl-policy configuration mode to set default maximum
connection parameters.
Syntax: [no] default max-conn 
—specifies maximum number of connections client can setup.
Example
ServerIronADX(config-http-trl-p1)# default max-conn 10

NOTE
Max-conn currently supports only HTTP/1.0.

Default exceed-action
Use the default exceed-action option in the http-trl-policy configuration mode to set the action to
take if a default exceeds the configured rate limit.
Syntax: [no] default exceed-action [reset | drop]
[reset | drop] specifies default request be reset or dropped if the limit is exceeded.
Example
ServerIronADX(config-http-trl-p1)# default exceed-action [reset | drop]

Syntax: [no] default exceed-action redirect   [port]
 and —specifies client request to be redirected to this new URL, if limit is exceeded.

NOTE

Use an asterisk (*) to keep the same domain or url.
ServerIronADX(config-http-trl-p1)# default exceed-action redirect *
/new/exceed.html http

NOTE
The same domain is used in the incoming packet.
The optional [port] specifies the new TCP port number for the redirected URL.
ServerIronADX(config-http-trl-p1)# default exceed-action redirect
/exceed.html http

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Logging for DoS Attacks

Logging for DoS Attacks
The following sections describe how to enable logging of DoS attacks.

Configuration commands
Use the following commands to enable logging of TCP connection rate and attack rate.
Syntax: [no] ip tcp conn-rate  attack-rate 
Syntax: [no] ip tcp conn-rate-change  attack-rate 
Syntax: [no] server max-conn-trap 
Parameters
The conn-rate  parameter specifies a threshold for the number of global TCP connections
per second that are expected on the ServerIron. A global TCP connection is defined as any packet
that requires session processing. For example, 1 SLB, 1 TCS, and 1 SYN-Guard connection would
equal 3 global TCP connections, since there are three different connections that require session
processing.

NOTE

The ServerIron ADX counts only the new connections that remain in effect at the end of the one
second interval. If a connection is opened and terminated within the interval, the ServerIron ADX
does not include the connection in the total for the server.
The attack-rate  parameter specifies a threshold for the number of TCP SYN attack packets
per second that are expected on the ServerIron.
Syslog entries are generated under the following circumstances:

• If the connection rate or attack rate on the ServerIron reaches 80% of the configured
threshold.

• If the connection rate or attack rate is still between 80% and 100% of the configured threshold
6 minutes after the last message.

• If the connection rate or attack rate exceeds 100% of the configured threshold.
• If the connection rate or attack rate exceeds 100% of the configured threshold, and has gone
up by the configured rate change percentage.

• One minute after the last message indicating that the connection rate or attack rate still
exceeds 100% of the configured threshold, and has gone up by the configured rate change
percentage.

• Three minutes after the last message, if the connection rate or attack rate is still between 80%
and 100% of the configured threshold, and has gone up by the configured rate change
percentage.
The server max-conn-trap  command specifies the number of seconds that elapse
between traps, where  can be from 1 to 300. The default is 30.
Example
ServerIronADX(config)# ip tcp conn-rate 10000 attack-rate 10000
ServerIronADX(config)# ip tcp conn-rate-change 50 attack-rate 100
ServerIronADX(config)# server max-conn-trap 30

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show server conn-rate
Use show server conn-rate to display the global TCP connection rate (per second) and TCP SYN
attack rate (per second). This command reports global connection rate information for the
ServerIron as well as for each real server.
ServerIronADX# show server conn-rate
Avail. Sessions
=
524286 Total Sessions
=
524288
Total C->S Conn
=
0 Total S->C Conn
=
0
Total Reassign
=
0 Unsuccessful Conn
=
0
last conn rate
=
0 max conn rate
=
0
last TCP attack rate =
0 max TCP attack rate =
0
SYN def RST
=
0 SYN flood
=
0
Server State - 1:enabled, 2:failed, 3:test, 4:suspect, 5:grace_dn, 6:active
Real Server
rs1

State
3

CurrConn
0

TotConn
0

LastRate
0

CurrRate
0

MaxRate
0

Maximum connections
Use max-conn to set the number of maximum connections on a global real server level (all ports) or
a single port.

All ports
One port

!
server real rs1 10.10.1.30
max-conn 1200
port http
port http max-conn 1000
port http url "HEAD /"
!

clear statistics dos-attack
Use clear statistics dos-attack to reset counters for ICMP and TCP SYN packet burst thresholds, as
displayed by show statistics dos-attack.
Example
ServerIronADX# clear statistics dos-attack
ServerIronADX# show statistics dos-attack

NOTE

The above commands are used to reset and verify counters for ICMP and TCP SYN packet burst
thresholds. The ServerIron ADX has introduced more a powerful feature to detect and block DoS
attacks. Please refer to the chapter titled: “Syn-Proxy and DoS Protection” on page 113 to view
details about verifying and clearing DOS-attack counters and filters.

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Maximum concurrent connection limit per client

Maximum concurrent connection limit per client
This feature restricts each client to a specified number of connections, based on the client’s
subnet, to prevent any one client from using all available connections.

Limiting the number of concurrent connections per client
This feature restricts each client to a specified number of concurrent connections, based on the
client’s subnet, to prevent any one client from using all available connections.
You associate a configured client subnet with a maximum permissible connection value. The
association is stored in the ServerIron by means of a Dynamic Prefix (DP) trie. The key stored in the
DP trie is the associated maximum connection value. The choice of the DP trie for storing the client
subnet allows to define different prefix lengths and subnet masks for each client subnet. Since the
DP trie lookup returns the longest prefix match, it is not required that all configured client subnets
should have the same subnet mask.
Configuring the max connection limit per client consists of the following tasks:

• Configure the maximum connections allowed per client address or prefix
• Applying configured number of maximum connections to a specific VIP

Configure the maximum number of connections
1. Begin by creating a policy set or group by entering commands such as the following.
ServerIronADX(config)#client-connection-limit max-conn1

Syntax: [no] client-connection-limit 
Enter a name for the policy set or group for .
Use the no form of the command to delete the policy group.
After creating a name, the CLI changes to the config-client-max-conn level.
2. Next, create the policy for maximum number of connections using one of the following
methods.
Create a policy for the maximum number of connections for specific clients
To set a maximum number of connections for a clients in a subnet, enter the a command such as
the following.
ServerIronADX(config)# client-connection-limit max-conn1
ServerIronADX(config-client-max-conn)# max-conn 100.1.1.0 255.255.255.0 10

In the example above, clients with IP addresses in the 100.1.1.0 subnet will be allowed only 10
connections.
Syntax: [no] max-conn [  
Enter the clients’ IP address and subnet mask for  
Enter a number from 0 to any value for . There is not default for this parameter.
Specifying a maximum number of connections for clients not specified in a policy
You can specify a default maximum number of connections for all clients that are not specified in
any max connection group by entering a command such as the following.

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ServerIronADX(config)# client-connection-limit max-conn1
ServerIronADX(config-client-max-conn)# max-conn default 10

In this example, all clients not specified in any max connection group will have a maximum of 10
connections.
Syntax: [no] max-conn [  default 
Enter a default maximum number of connections for 
Excluding clients from maximum connection policy
If you want certain clients to be excluded from any maximum connection policies, enter a command
such as the following.
ServerIronADX(config)# client-connection-limit max-conn1
ServerIronADX(config-client-trl)# max-conn 100.1.4.0 255.255.255.0 exclude

In this example, clients in the 100.1.4.0 subnet will be excluded for any maximum connection rules.
Syntax: [no] max-conn [  exclude
Displaying the maximum number of connections for clients that are currently connected
To show the maximum number connection policy for a client that is currently connected, enter
command such as the following on the barrel processor (BP) console.
ServerIronADX1# show conn pass1 0
Max Count: 2500 Total Count: 55
IP address Mask config hit denied
0.0.0.0 0.0.0.0 10 0 0
120.20.1.0 255.255.255.192 12 0 0
120.20.1.16 255.255.255.240 15 0 0
120.20.1.21 255.255.255.255 exclude
120.20.1.23 255.255.255.255 exclude
120.20.1.24 255.255.255.255 15 20 5
Current connections:
VIP 20.20.1.6: 15
120.20.1.25 255.255.255.255 exclude
120.20.1.27 255.255.255.255 exclude
Current connections:
VIP 20.20.1.6: 20
120.20.1.29 255.255.255.255 exclude
120.20.1.30 255.255.255.255 15 20 5
Current connections:
VIP 20.20.1.6: 15
120.20.1.33 255.255.255.255 exclude
ServerIronADX1#

0 0
0 0

0 0
20 0

0 0

20 0

Syntax: show connection-limit  
Enter the name of the max connection policy for .
Enter the starting entry for 

Binding the policy to a VIP
After creating a maximum connection policy, bind it to a VIP by entering commands such as the
following.
ServerIronADX(config)#server virtual-name-or-ip virt-2
ServerIronADX(config-vs-virt-2)#client-max-conn-limit max-conn1

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Firewall load balancing enhancements

Syntax: [no] client-max-conn-limit 
Enter the name of the max connection policy for .

NOTE

When the policy is bound to a VIP, the policy limits the number of connections that a client can have
on any real server on the network.

Firewall load balancing enhancements
This section contains the following sections:

•
•
•
•

“Enabling firewall strict forwarding”
“Enabling firewall VRRPE priority”
“Enabling track firewall group”
“Enabling firewall session sync delay”

Enabling firewall strict forwarding
To enable load balancing only when traffic is going to a firewall, use the following command.
ServerIronADX(config)# server fw-strict-fwd

Syntax: server fw-strict-fwd
Use the server fw-strict-fwd command in the global configuration mode. Without this command,
when the ServerIron receives traffic that matches the firewall flow session and the traffic is not
received from a firewall, then the ServerIron assumes that it needs to be load balanced to a
firewall.
This command checks to ensure that traffic is going to a firewall and only then does the ServerIron
load balance it to a firewall.

Enabling firewall VRRPE priority
To configure VRRPE state to track the firewall group state, use the following command.
ServerIronADX(config)# server fw-g 2
ServerIronADX(config-tc-2)#fw-vrrpe-priority
ServerIronADX(config-tc-2)#

Syntax: fw-vrrpe-priority 
Use the fw-vrrpe-priority command in the fw-group configuration mode.  is the VRRPE
priority associated with current firewall group state. Valid values are 1 to 255.

NOTE

This command can be used with the track-fw-group command below to force VRRPE state to track
the firewall group state for a specific vrid.

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Enabling track firewall group
To enable track-fw-group to track the firewall group state, use the following commands.
ServerIronADX(config)#int ve 1
ServerIronADX(config-vif-1)# ip vrrp-e vrid 1
ServerIronADX(config-vif-1-vrid-1)# track-fw-group

Syntax: track-fw-group 
Use the track-fw-group command under the VRRPE config level.  is the firewall group
that needs to be tracked for this VRRPE. This command is used along with the fw-vrrpe-priority
command to force VRRPE state to track the FW group state. This command works similar to the
track-port command. When the firewall group state is STANDBY, then the VRRPE current priority is
decremented by the fw-vrrpe-priority specified under that firewall group. It is recommended that
you track only the firewall group state and no other port, because tracking firewall group state
automatically tracks the router ports, firewall paths, and more.

Enabling firewall session sync delay
To enable server fw-sess-sync-delay, use the following command.
ServerIronADX(config)#server fw-sess-sync-delay 10

Syntax: server fw-sess-sync-delay 
Use the server fw-sess-sync-delay command added at the global config level.  is the number
of seconds to delay the fast session sync after one of the ServerIrons is reloaded in HA FWLB. Valid
values range from 1 to 100. This command can be useful in configurations where many real
servers or firewalls are configured.

Syn-cookie threshhold trap
To configure the syn cookie attack rate threshold, use the following command.
ServerIronADX(config)# server syn-cookie-attack-rate-threshold 10000

Syntax: syn-cookie-attack-rate-threshold 
The  variable is a decimal number ranging from 1 to 10000000.
If the current syn cookie attack rate is larger than the syn cookie attack rate threshhold, the
snTrapSynCookieAttackThreshReached trap is generated.
To configure the snTrapSynCookieAttackThreshReached trap interval, use the following command.
ServerIronADX(config)# server max-conn-trap-interval 10

Syntax: server max-conn-trap-interval 
The  variable is a decimal number in seconds. The default value is 60 seconds.

Service port attack protection in hardware
A ServerIron can be enabled to deny traffic that is destined to VIP address but to a port that is not
defined under a VIP. Such traffic can be dropped in hardware without impacting the MP or BP CPUs.

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Traffic segmentation

NOTE

VIP protection works for IPv4 VIPs alone and cannot be enabled for IPv6 VIPs.
You can enable this feature globally by entering the following command.
ServerIronADX(config)# server vip-protection

Syntax: [no] server vip-protection
Once enabled, the VIP protection applies to all existing and new VIP configurations.
If you want to enable the feature on individual VIPs, enter the following command.
ServerIronADX(config)# server virtual-name-or-ip v1
ServerIronADX(config-vs-v1)# vip-protection

NOTE

A reload is required for VIP protection to take effect when enabled on a global level using the server
vip-protection command.
Syntax: [no] vip-protection
VIP protection adds CAM entries for each defined virtual port associated with each VIP. An
additional CAM entry is defined for ICMP traffic destined to each VIP. An entry to drop the traffic is
also added in the CAM for each VIP, which makes sure that traffic destined to any destination port
other than the virtual ports is dropped by hardware.
NOTES:

• VIP protection does not support complex protocols such as FTP, TFTP, MMS, RTSP, SIP, that
establish data connections based on the information exchanged on control channel.

• VIP protection cannot be enabled on a VIP that is part of a dynamic NAT address pool.
• VIP protection cannot be used along with features that require binding of virtual default port to
real server default port.

Traffic segmentation
The traffic segmentation feature allows you to create segmentation among multiple L4-7 SLB
domains of a single ServerIron ADX. The purpose of this feature is to ensure that traffic from one
SLB domain to another SLB domain goes through the upstream firewall and does not get switched
locally. This can be accomplished using either of the following methods:

• VLAN bridging
• Using the server use-session-for-vip-mac
These features help meet some of the security requirements for PCI compliance.

VLAN bridging
The VLAN bridging feature allows you to bridge together two VLANs so that packets will be layer-2
switched from one VLAN to the other. When two VLANs are bridged together, all packets received
on one VLAN are translated to the other VLAN and switched.

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When used for creating Layer-2 segmentation among SLB domains, this feature ensures that traffic
from one SLB domain destined to another SLB domain goes through the upstream gateway and is
not switched locally. This ensures that every packet between a client and server has to go through
the ServerIron ADX for load-balancing.
Figure 1 is an example of the VLAN bridging feature deployed in a one-armed topology. In this
example when traffic from “Domain1” is bound for“Domain2” it is translated from VLAN 2 to VLAN
12 at the ServerIron ADX. It is then able to reach the “Gateway” on VLAN 12. The return traffic from
the “Gateway” leaves on VLAN 13 and is translated to VLAN 3 at the ServerIron ADX. It is then able
to reach “Domain2” on VLAN 3.

FIGURE 1

VLAN bridging in a one-armed topology

Gateway

Vlans
12, 13, 14

ServerIron ADX

Vlans
2, 3, 4, 12, 13, 14

Layer-2
Switch

Vlan -Bridging
2-12, 3-13, 4-14

Vlan 2

Domain1

Vlan 3

Domain2

Vlan 4

Domain3

The topology described in Figure 1 can be implemented in the hot-standby configuration as shown
in Figure 2.

FIGURE 2

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Traffic segmentation

Gateway

Vlans
12, 13, 14

ServerIron ADX
(active)

Vlans
2, 3, 4, 12, 13, 14

Layer-2
Switch

Vlans
2, 3, 4, 12, 13, 14

Vlan -Bridging
2-12, 3-13, 4-14

ServerIron ADX
(standby)
Vlan -Bridging
2-12, 3-13, 4-14

Vlan 2

Domain1

Vlan 3

Domain2

Vlan 4

Domain3

Considerations when configuring VLAN bridging
The following considerations apply when configuring VLAN bridging:

• Up to 64 unique-pair VLAN bridges can be configured.
• A VLAN cannot be part of two different VLAN bridges.
• Two VLANs forming a bridge must have the same set of member ports on the ServerIron ADX
where they are joined.

• The Control VLAN (4094) and system default VLAN cannot be used for VLAN bridging.
• The hot-standby scenario is the only High Availability configuration supported with VLAN
bridging. In a hot-standby scenario with one-armed topology, after fail over, the existing session
may not be continued if the Layer-2 Switch in the middle cannot learn the MAC address of the
Gateway through the newly-active ServerIron ADX in time.

• VLAN bridging is only supported with switch code. It is not supported with the ServerIron ADX
router code.

• VLAN bridging is not supported with the SYN-proxy feature.
• All ports within a VLAN bridge must be tagged members of a VLAN and its associated bridged
VLAN.

• MAC learning is shared for VLANs that are bridged together.

Configuring VLAN bridging
The vlan-bridge command is used to configure VLAN bridging. To configure VLAN 10 and VLAN 12
for VLAN bridging, use the following command.
ServerIron(config)# vlan-bridge 10 12

Syntax: [no] vlan-bridge  
The  variables specify the pair of VLANs that you want to create VLAN bridging for.

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NOTE

Once a bridge is created between two VLANs, the VLAN configuration mode for those VLANs is
disabled. You must remove a VLAN bridge if you want to make any changes to a VLAN contained
within the VLAN bridge.

Example
The following example configures two VLANs with each containing the same ports and a VLAN
bridge configured between them.
ServerIron(config)# vlan 222 by port
ServerIron(config-vlan-222)# tagged ethernet 1 ethernet 4
ServerIron(config-vlan-222)# exit
ServerIron(config)# vlan 333 by port
ServerIron(config-vlan-333)# tagged ethernet 1 ethernet 4
ServerIron(config-vlan-333)# exit
ServerIron(config)# vlan-bridge 222 333

Displaying VLAN bridge information
You can display information about VLAN bridging using the show vlan and show vlan-bridge
commands.
Using the show vlan command, a VLAN bridge is displayed as shown in the following.
ServerIron# show vlan
Total PORT-VLAN entries: 3
Maximum PORT-VLAN entries: 64
PORT-VLAN 1, Name DEFAULT-VLAN,
Untagged Ports: 2 3 5 6 7
Tagged Ports: None
Uplink Ports: None
DualMode Ports: None
PORT-VLAN 222, Bridge VLAN 333,
Untagged Ports: None
Tagged Ports: 1 4
Uplink Ports: None
DualMode Ports: None
PORT-VLAN 333, Bridge VLAN 222,
Untagged Ports: None
Tagged Ports: 1 4
Uplink Ports: None
DualMode Ports: None

Priority level0, Spanning tree Off
8 9 10

Name [None], Priority level0, Spanning tree Off

Name [None], Priority level0, Spanning tree Off

Syntax: show vlan [ | ethernet  ]
Using the  variable limits the display to the single VLAN whose ID is specified.
Using the ethernet  option limits the display to VLANs configured on the specified port.

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The contents of the display are defined in the following table.

TABLE 2

Display from show vlan command

This field...

Displays...

PORT-VLAN

The VLAN ID of the PORT VLAN configured.

Bridge VLAN

The VLAN ID of the associated bridge VLAN.

Name

The name of the VLAN as configured. If no name is configured, “{None]” is
displayed

Priority level

The QoS priority as configured. If no priority value is configured the value
displayed will be “0”.

Spanning tree

Displays the value of spanning tree protocol on this VLAN. Values can be “On”
or “Off”.

Untagged Ports

Displays the untagged port members of the VLAN.

Tagged Ports

Displays the tagged port members of the VLAN.

Uplink Ports

Displays the uplink port members of the VLAN.

DualMode Ports

Displays the port members of the VLAN that are in dual mode.

You can use the show vlan-bridge command to show all of the bridged VLANs as follows.
ServerIron# show vlan-bridge
IN-VLAN
Bridge VLAN
222
333
333
222

Syntax: show vlan-bridge
The contents of the display are defined in the following table.

TABLE 3

40

Display from show vlan-bridge command

This field...

Displays...

IN-VLAN

The VLAN ID of the PORT VLAN configured.

Bridge VLAN

The VLAN ID of the associated bridge VLAN.

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Traffic segmentation using the use-session-for-vip-mac command
By default, as long as there is a session match, packets with a destination IP address of a VIP are
processed regardless of whether the destination MAC is addressed to the ServerIron ADX or not.
With the server use-session-for-vip-mac command configured, only packets with a destination MAC
address of the ServerIron ADX are processed. Packets with a destination IP address of a VIP but a
destination MAC address not belonging to the ServerIron ADX are treated as pass-through traffic.
This feature is useful in traffic segmentation scenarios such as that shown in Figure 3. In the
example, packets entering the ServerIron ADX from rs-domain1 bound for vs-domain2 would, by
default, be switched at the ServerIron ADX to go directly to rs-domain2. If the server
use-session-for-vip-mac command is configured on the ServerIron ADX, the packets are sent up to
the firewall where they are subject to the security settings before being sent back down to the
ServerIron ADX for forwarding to the VIP.

FIGURE 3

Traffic Segmentation
VLAN 20

VLAN 40

Firewall

e1

e2

IP: 192.168.32.1

IP: 192.168.33.1
link 2

link 1

ServerIron ADX

e2

e1
link1

vs-domain1: 192.168.32.10
e4

rs-domain1:
192.168.32.11
GW: 192.168.32.1

vs-domain2: 192.168.33.10
e4

rs-domain2:
192.168.33.11
GW: 192.168.33.1

This feature is configured as shown in the following.
ServerIron(config)# server use-session-for-vip-mac

Syntax: [no] server use-session-for-vip-mac

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DNS attack protection
The ServerIron ADX can be configured to provide DNS attack protection to VIP traffic. This
protection is provided by performing a deep packet scan and then classifying DNS requests based
on the following: query type, query name, RD flag or the DNSSEC “OK” bit in the EDNS0 header.
Based on this classification, the following actions can be taken either individually or in
combination: forward traffic to a specific server group, drop packets, log events or rate limit DNS
traffic from the identified client.
Figure 4 displays a potential configuration of this feature. For this configuration, a DNS deep packet
inspection with DNS filtering could be configured to perform the following actions.
Block specified types of DNS queries – for example:

• Block queries with the RD flag
• Block queries with the DNSSEC “OK” bit set.
Log specified types of DNS queries – for example:

• Log the number of queries to “www.mydomain.com”
Redirect specified DNS queries to a different set of DNS servers – for example:

• Forward all requests with the DNSSEC “OK” bit to a separate set of servers.
• Forward all queries for the “ www.mydomain.com” to a different group of servers
Impose rate limiting for certain types of DNS queries per client.– for example:

• Rate limit queries to “ www.mydomain.com” for each client
• Rate limit the number of MX queries that a client can send.
FIGURE 4

DNS attack protection

DNS client A
DNS Server

ServerIron ADX

DNS client B

Internet
VIP
200.200.200.1

DNS Server

Notes:
1. Only DNS requests using UDP transport (port 53) is supported.
2. If an incoming request matches an existing L4 session (including sticky sessions), DNS filtering
will not apply on the request
3. Query not expected across multiple packet
4. When multiple queries are in a single DNS packet, only first RR will be processed
5. There is no csw dns rule to identify DNS Root requests.

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Configuring DNS attack protection
Configuring DNS attack protection involves the following steps:
1. Create DNS DPI rules.
In this step you specify the filtering parameters under a rule. A packet must match all of the
filtering parameters defined under a rule to match the rule.
2. Create a DNS DPI policy and bind the rules to it.
In this step you bind a rule to a policy and specify the action to be taken if a packet matches
the rule.
3. Bind a DNS DPI policy to a Virtual port.
In the final configuration step, you bind a policy to a virtual port. Then, all packets destined to
that virtual are subject to the DNS DPI rules and policies defined in steps 1 and 2.
In addition, there are global commands that you can optionally configure to apply to all DNS attack
protection configurations.

Defining DNS rules to filter packets
The DNS rules define the parameters that the DNS packets are filtered on. Rules can be defined for
the following parameters:

•
•
•
•

Query-name
Query type
RD flag
DNS Sec bit

To define a rule, you must first define the rule and then define the DNS filtering rule parameters
under it as shown.
ServerIron(config)# csw-rule rule1 udp-content dns

Syntax: [no] csw-rule  udp-content dns
The  variable specifies a name for the rule that must be unique across all CSW
functionality. A maximum of 512 DNS DPI rules can be configured.
The filtering rule parameters are defined within the rule as shown. The rule parameters function as
an inherent “AND” which means that all of the parameters must be met for the rule to be matched.
ServerIron(config)# csw-rule rule1 udp-content dns
ServerIron(config-csw-dns-rule-rule1) query-type MX
ServerIron(config-csw-dns-rule-rule1) query-name abc.com
ServerIron(config-csw-dns-rule-rule1) query-rd-flag on
ServerIron(config-csw-dns-rule-rule1) query-dnssec-ok off

Syntax: query-type 
The  variable specifies the DNS query type to match on.
Syntax: query-name 
The  variable specifies the name of the DNS query type to match on.
Syntax: query-rd-flag { on | off}
The on parameter is matched if the RD flag is set in the packet.

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The off parameter is matched if the RD flag is not set in the packet.
Syntax: query-dnssec-ok { on | off}
The on parameter is matched if the DNSSEC bit is set in the packet.
The off parameter is matched if the DNSSEC bit is not set in the packet.

Order of Rule matching
Matching on the query-name is first attempted in the order of the length of the query-name. THis is
followed by the rules without query-name (only if needed), in the order they were added to the
policy. If two rules with query-name have the same length of the string, then the alphabetical order
will take precedence. And, when two rules with query-name are exactly the same string, then the
order in which the rules are added to the policy, will take precedence.
For example, initially the order of rules in a policy is:
1. Rule to match query-name www.brocade.com
2. Rule to match query-type A & query-RDflag ON
Adding a couple of new rules to match query-name www.mywebsite.com and to match query-type
AAAA will rearrange the rules in policy as
1. Rule to match query-name www.brocade.com
2. Rule to match query-name www.mywebsite.com
3. Rule to match query-type A & query-RDflag ON
4. Rule to match query-type AAAA
The policy level configuration 'evaluate-generic-first' would reverse this default behavior by first
matching the rules not based on query-names. In that case, same rules would be ordered as
1. Rule to match query-type A & query-RDflag ON
2. Rule to match query-type AAAA
3. Rule to match query-name www.brocade.com
4. Rule to match query-name www.mywebsite.com

Creating a DNS DPI policy and bind the rules to it
A DNS DPI policy specifies the action to take when a previously defined rule is matched. A DNS DPI
policy is defined as shown.
ServerIron(config)# csw-policy DNSpolicy1 type dns-filter

Syntax: [no] csw-policy  type dns-filter
The  variable specifies a name for the CSW policy that must be unique across all
CSW functionality.

NOTE
A maximum of 255 DNS policies can be configured on a ServerIron ADX. Also, the total number of
rules that can be bound to a single policy is 512 and the global limit for binding rules to a policy is
2500. For example, if you bind 500 rules to each of 5 policies you will reach 2500 which is the global
limit for binding rules to a policy.

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Once a packet matches a configured filter, the following actions can be specified:

•
•
•
•

drop
Redirect to a server or server group
rate-limit
log (log is a secondary action and cannot be specified by itself)

The actions are configured within the DNS DPI policy as shown in the following.
ServerIron(config)# csw-policy DNSpolicy1 type dns-filter
ServerIron(config-csw-dns-policy-P1) match rule1 redirect 1 log
ServerIron(config-csw-dns-policy-P1) match rule2 drop log
ServerIron(config-csw-dns-policy-P1) match rule3 rate-limit monitor-interval 2
conn-rate 20 hold-down-time 2 log
ServerIron(config-csw-dns-policy-P1) default drop

Syntax: { match  | default } {drop | redirect | rate-limit monitor-interval
 conn-rate  hold-down-time  } { log | no-log }
If the default option is configured under a policy, DNS query packets that do not match any of the
rules bound to that policy are acted on by the configured policy. In the example above, a DNS query
that does not match rules rule1, rule2, and rule3 will be dropped.
The drop parameter directs the ServerIron ADX to drop any packets that match the filter.
The redirect parameter directs the ServerIron ADX redirect any packets that match the filter to a
server or server group specified by  or 
The rate-limit parameter directs the ServerIron ADX to rate limit packets that match the filter at the
monitor-interval specified by the  variable, the conn-rate specified by the
 and the hold-down-time specified by the  variable.
The log parameter directs the ServerIron ADX to report the number of times that a rule has been
matched within a 5 second interval. log is a secondary action and cannot be specified by itself.

Binding a DNS DPI policy to a Virtual port
To take effect, a DNS DPI policy must be bound to a virtual port. The following applies to this
binding:

• a CSW DNS policy can only be applied to port DNS
• You can bind only one policy per virtual port
• You cannot bind a DNS policy to a virtual port if another CSW policy is already bound to port
DNS.

• Once a DNS policy is bound to a port, any DNS query that comes to the virtual server will be
matched against the rules bound to that policy and any associated action will be take on the
match.
You can bind a DNS DPI policy to a virtual port as shown.
ServerIron(config) server virtual vip1 10.120.62.53
ServerIron(config-vs-vip1)# port dns csw-policy DNSpolicy1
ServerIron(config-vs-vip1)# port dns csw

Syntax: [no] port dns csw-policy 
The  variable specifies the name of the policy to be bound to a virtual port.
Syntax: [no] port dns csw

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This command enables DNS content switching.

Configuring global commands for DNS attack protection
You can optionally configure the following to apply to all DNS attack protection configurations:

• Dropping all DNS packets that are fragmented
• Dropping all DNS packets with multiple queries
• Dropping all DNS packets that are malformed
To configure a ServerIron ADX to drop all DNS packets that are fragmented, use the server dns-dpi
drop-frag-pkts command as shown.
ServerIron(config) server dns-dpi drop-frag-pkts

Syntax: [no] server dns-dpi drop-frag-pkts
To configure a ServerIron ADX to drop all DNS packets with multiple queries, use the server dns-dpi
drop-multiple-query-pkts command as shown.
ServerIron(config) server dns-dpi drop-multiple-query-pkts

Syntax: [no] server dns-dpi drop-multiple-query-pkts
To configure a ServerIron ADX to drop all DNS packets that are malformed, use the server dns-dpi
drop-incomplete-malformed-pkts command as shown.
ServerIron(config) server dns-dpi drop-incomplete-malformed-pkts

Syntax: [no] server dns-dpi drop-incomplete-malformed-pkts

Configuring the ADX to drop requests if servers in redirect actions are down
You can configure the ServerIron ADX to drop requests if servers in redirect actions are down as
shown.
ServerIron(config-csw-pol-p1) dns-drop-on-fwd-fail

Syntax: [no] dns-drop-on-fwd-fail

Configuring the ADX to evaluate rules without query name first
You can configure the ServerIron ADX to evaluate rules without query name first as shown.
ServerIron(config-csw-pol-p1) evaluate-generic-first

Syntax: [no] evaluate-generic-first

Displaying DNS attack protection information
The following information can be displayed regarding DNS attack protection.

• DNS DPI policy counters
• IP addresses held down by a rate limit action

DIsplaying DNS DPI policy counters
DNS DPI policy counters can be displayed for a specified DNS policy as shown.

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ServerIron# show csw-dns-policy p1
Rule Name
Action
Hit Count
d2
redirect
0
d4
drop
0
d3
rate-limit
0
default
drop
0

1

Rate Limit Held Down
0
0
0
0

You can display the DNS DPI policy counters for all DNS policies as shown.
ServerIron# show csw-dns-policy
Total Policies:3
Policy Name
:p1
Rule Name
d5
d1
d2
d3
default
Policy Name
Rule Name
Policy Name
Rule Name
d3

:p2
Action
:p3
Action
drop

Total Rules:6
Action
redirect
redirect
redirect
rate-limit
drop

Hit Count

Hit Count
0

Total Rule Actions:6
Bind Count:2
Hit Count
Rate Limit Held Down
0
0
0
0
0
0
0
0
0
0
Bind Count:0
Rate Limit Held Down
Bind Count:0
Rate Limit Held Down
0

Syntax: show csw-dns-policy 
The  variable species a DNS policy that you want to display DNS DPI policy counters
for.
CSW DNS DPI policy counters can be cleared for a specified DNS policy as shown.
ServerIron# clear csw-policy p1

Syntax: clear csw-policy 

DIsplaying IP addresses held down by a rate limit action
IP addresses held down by a rate limit action can be displayed for an application processor (BP)
from the rconsole as shown.
ServerIron ADX# rconsole 1 1
ServerIron ADX1/1# show security holddown
source
destination
vers
attempt
30.30.30.4
0.0.0.3
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Access Control List

2

How ServerIron processes ACLs
This chapter describes the Access Control List (ACL) feature. ACLs allow you to filter traffic based on
the information in the IP packet header. Depending on the Brocade device, the device may also
support Layer 2 ACLs, which filter traffic based on Lay 2 MAC header fields.
You can use IP ACLs to provide input to other features such as distribution lists and rate limiting.
When you use an ACL this way, use permit statements in the ACL to specify the traffic that you want
to send to the other feature. If you use deny statements, the traffic specified by the deny
statements is not supplied to the other feature.
There are two ways that IPv4 ACLs are processed in Brocade devices: in software and in hardware.
This processing differs depending on the software release that you are running. These differences
are described in the following sections.

Prior to release 12.3.01
Prior to release 12.3.01, IPv4 ACLs were processed as described in the following:
For deny actions:
All deny packets are dropped in hardware.
For permit actions:
For pass-through traffic, packets are processed in hardware.
For Layer 4 - 7 traffic, packets are forwarded to the BPs and the BPs perform the ACL
processing.

Beginning with release 12.3.01 and later
Beginning with release 12.3.01, IPv4 ACLs are processed as described in the following:
For deny actions:
All deny packets are dropped in hardware.
For permit actions:
For pass-through traffic, packets are processed in hardware.
For Layer 4 - 7 traffic, packets are processed in hardware and then forwarded to the BPs. The
BPs do not take any action on the ACLs.

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Backwards compatibility option:
You can use the ip flow-based-acl-enable command to provide backwards compatibility for IPv4
ACL processing. If this command is configured, Layer 4 - 7 traffic, packets are processed in
hardware and then forwarded to the BPs where the BPs also process the ACLs. This command
is configured as shown in the following.
ServerIronADX(config)# ip flow-based-acl-enable

Syntax: ip flow-based-acl-enable

Rule-based ACLs
Some Brocade devices process the traffic that ACLs filter in hardware. This document refers to this
type of ACLs as rule-based ACLs. These ACLs are programmed into hardware at startup or as a new
ACL is entered.
Rule-based ACLs program the ACL entries you assign to an interface into Content Addressable
Memory (CAM) space allocated for the port(s). Devices that use rule-based ACLs program the ACLs
into the CAM entries and use these entries to permit or deny packets in the hardware, without
sending the packets to the CPU for processing.
Rule-based ACLs are supported on physical interfaces, ve interfaces, trunk groups, and VIPs.
To configure a standard ACL and apply it to VIP, enter the following commands.
ServerIronADX(config)# access-list 1 deny host 209.157.22.26
ServerIronADX(config)# access-list 1 deny 209.157.29.12
ServerIronADX(config)# access-list 1 deny host IPHost1
ServerIronADX(config)# access-list 1 permit any
ServerIronADX 1000(config)#server virtual-name-or-ip vs-80
ServerIronADX 1000(config-vs-vs-80)#acl-id 1
ServerIronADX 1000(config-vs-vs-80)#write memory

Configuration guidelines for rule-based ACLs: general guidelines
Consider the following guidelines:

• Rule-based ACLs support only one ACL per port. The ACL of course can contain multiple entries
(rules). For example, rule-based ACLs do not support ACLs 101 and 102 on port 1, but
rule-based ACLs do support ACL 101 containing multiple entries.

• If you change the content of an ACL (add, change, or delete entries), you must remove and then
reapply the ACL to all the ports that use it. Otherwise, the older version of the ACL remains in
the CAM and continues to be used. You can easily re-apply ACLs using the ip rebind-acl 
|  | all command. Refer to “Applying an ACLs to interfaces” on page 69.

NOTE

Brocade recommends that you also remove and reapply a changed ACL.

• ACL statistics are not supported with rule-based rate limiting.
• If you use the  parameter with an extended ACL, the device uses the CPU to filter
packets using the ACL. The CPU is required to filter the ICMP message type.

• You can use PBR and rule-based ACLs on the same port. However, Brocade recommends that
you use exactly the same ACL for each feature. Otherwise, it is possible for the ACL’s Layer 4
CAM entry to be programmed incorrectly and give unexpected results.

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How fragmented packets are processed
The descriptions for rule-based ACLs above apply to non-fragmented packets. The default
processing of fragments by rule-based ACLs is as follows:

• The first fragment of a packet is permitted or denied using the ACLs. The first fragment is
handled the same way as non-fragmented packets, since the first fragment contains the Layer
4 source and destination application port numbers. The device uses the Layer 4 CAM entry if
one is programmed, or applies the interface's ACL entries to the packet and permits or denies
the packet according to the first matching ACL.

• For other fragments of the same packet, one of the following occurs:
• If the device has a CAM entry for the packet and has not been configured to send the
fragments to the CPU, the device uses the CAM entry to forward the fragments in
hardware.
The fragments are forwarded even if the first fragment, which contains the Layer 4
information, was denied. Generally, denying the first fragment of a packet is sufficient,
since a transaction cannot be completed without the entire packet. However, for stricter
fragment control, you can send fragments to the CPU for filtering.

• If the device is configured to send fragments to the CPU for filtering, the device compares
the source and destination IP addresses to the ACL entries that contain Layer 4
information.

• If the fragment’s source and destination addresses exactly match an ACL entry that
has Layer 4 information, the device assumes that the ACL entry is applicable to the
fragment and permits or denies the fragment according to the ACL entry. The device
does not compare the fragment to ACL entries that do not contain Layer 4 information.

• If both the fragment’s source and destination addresses do not exactly match an ACL
entry, the device skips the ACL entry and compares the packet to the next ACL entry.
This is true even if either the source or destination address (but not both) does exactly
match an ACL entry.

• If the source and destination addresses do not exactly match any ACL entry on the
applicable interface, the device drops the fragment.

NOTE

By default, 10 Gigabit Ethernet modules also forward the first fragment instead of using the
ACLs to permit or deny the fragment.
You can modify the handling of denied fragments. In addition, you can throttle the fragment rate on
an interface that used rule-based ACLs. Refer to “Dropping all fragments that exactly match a
flow-based ACL” on page 72 and “Enabling ACL filtering of fragmented packets” on page 73.

Default ACL action
The default action when no ACLs is configured on a device is to permit all traffic. However, once you
configure an ACL and apply it to a port, the default action for that port is to deny all traffic that is
not explicitly permitted on the port:

• If you want to tightly control access, configure ACLs consisting of permit entries for the access
you want to permit. The ACLs implicitly deny all other access.

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• If you want to secure access in environments with many users, you might want to configure
ACLs that consist of explicit deny entries, then add an entry to permit all access to the end of
each ACL. The software permits packets that are not denied by the deny entries.

Types of IP ACLs
Rule-based ACLs can be configured as standard or extended ACLs. A standard ACL permits or
denies packets based on source IP address. An extended ACL permits or denies packets based on
source and destination IP address and also based on IP protocol information.
Standard or extended ACLs can be numbered or named. Standard numbered ACLs have an idea of
1 – 99. Extended numbered ACLs are numbered 100 – 199. IDs for standard or extended ACLs can
be a character string. In this document, ACLs with a string ID is called a named ACL.

ACL IDs and entries
ACLs consist of ACL IDs and ACL entries:

• ACL ID – An ACL ID is a number from 1 – 99 (for a standard ACL) or 100 – 199 (for an extended
ACL) or a character string. The ACL ID identifies a collection of individual ACL entries. When you
apply ACL entries to an interface, you do so by applying the ACL ID that contains the ACL entries
to the interface, instead of applying the individual entries to the interface. This makes applying
large groups of access filters (ACL entries) to interfaces simple.

NOTE

This is different from IP access policies. If you use IP access policies, you apply the individual
policies to interfaces.

• ACL entry – An ACL entry are the filter commands associated with an ACL ID. These are also
called “statements”. The maximum number of ACL entries you can configure is a system-wide
parameter and depends on the device you are configuring. You can configure up to the
maximum number of entries in any combination in different ACLs. The total number of entries
in all ACLs cannot exceed the system maximum.

• Layer 3 switch code on devices can support up to 4096 ACL entries.
You configure ACLs on a global basis, then apply them to the incoming or outgoing traffic on
specific ports. You can apply only one ACL to a port’s inbound traffic and only one ACL to a port’s
outbound traffic. The software applies the entries within an ACL in the order they appear in the
ACL’s configuration. As soon as a match is found, the software takes the action specified in the ACL
entry (permit or deny the packet) and stops further comparison for that packet.

Support for up to 4096 ACL entries
You can configure up to 4096 ACL entries on devices that have enough space to hold a
startup-config file that contains the ACLs.
For system-max configuration of 4096 ACL rules, the Ip access-group max-l4-cam parameter must
be set to 4096. To configure the maximum ACL rule limit of 4096 ACL rules, the following must be
set:

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1. The system-max for Ip-filter-sys value must be set to 4096.
ServerIronADX(config)# system-max ip-filter-sys 4096

2. The Ip access-group max-l4-cam parameter must be set to 4096 on the interface that the ACL
will be applied
ServerIronADX(config)# interface ethernet 1
ServerIronADX(config-if-e1000-1)# ip access-group max-l4-cam 4096

3. Execute the write memory command to save the running configuration to the startup-config
reload the ServerIron ADX.
The actual number of ACLs you can configure and store in the startup-config file depends on the
amount of memory available on the device for storing the startup-config. To store 4096 ACLs in the
startup-config file requires at least 250K bytes, which is larger than the space available on a
device’s flash memory module.
You can load ACLs dynamically by saving them in an external configuration file on flash card or TFTP
server, then loading them using one of the following commands.
copy tftp running-config  
ncopy tftp   running-config

In this case, the ACLs are added to the existing configuration.

ACL entries and the Layer 4 CAM
Rule-based ACLs both use Layer 4 CAM entries.

Aging out of entries in the Layer 4 CAM
On a ServerIron ADX device, the device permanently programs rule-based ACLs into the CAM. The
entries never age out.

Displaying the number of Layer 4 CAM entries
To display the number of Layer 4 CAM entries used by each ACL, enter the following command.
ServerIronADX(config)# show access-list all
Extended IP access list 100 (Total flows: N/A, Total packets: N/A, Total rule cam
use: 3)
permit udp host 192.168.2.169 any (Flows: N/A, Packets: N/A, Rule cam use: 1)
permit icmp any any (Flows: N/A, Packets: N/A, Rule cam use: 1)
deny ip any any (Flows: N/A, Packets: N/A, Rule cam use: 1)

Syntax: show access-list  |  | all
The Rule cam use field lists the number of CAM entries used by the ACL or entry. The number of
CAM entries listed for the ACL itself is the total of the CAM entries used by the ACL’s entries.

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Specifying the maximum number of CAM entries for rule-based ACLs
For rule-based ACLs, you can adjust the allocation of Layer 4 CAM space for use by ACLs, on an IPC
or IGC basis and on 10 Gigabit Ethernet modules. The new allocation applies to all the ports
managed by the IPC or IGC or 10 Gigabit Ethernet module.
Most ACLs require one CAM entry for each ACL entry (rule). The exception is an ACL entry that
matches on more than one TCP or UDP application port. In this case, the ACL entry requires a
separate Layer 4 CAM entry for each application port on which the ACL entry matches.
Make sure you specify a maximum that is equal to or greater than the largest number of entries
required by an ACL applied to any of the ports managed by the same IPC or IGC. For example, if port
1 will have an ACL that requires 250 entries, make sure 250 is the lowest number of entries you
specify for any port on IPC 1 (the IPC that manages ports 1 – 24).
To specify the maximum number of CAM entries the device can allocate for rule-based ACLs, enter
commands such as the following.
ServerIronADX(config)# interface ethernet 1/1
ServerIronADX(config-if-1/1)# ip access-group max-l4-cam 50

This command allows up to 50 ACL entries on each port managed by the IPC or IGC that manages
port 1/1.
Syntax: [no] ip access-group max-l4-cam 
The  parameter specifies the number of CAM entries and can be from 10 – 2048. The
default depends on the device.
The command is valid at the interface configuration level. However, the device applies the change
to all ports managed by the same IPC or IGC. Regardless of the port number, when you save the
change to the startup-config file, the CLI applies the command to the first port managed by the IPC
or IGC. For example, if you enter the command on port 3, when you save the configuration change,
the CLI enters the ip access-group max-l4-cam command under port 1 in the startup-config file.

NOTE
If you enter the command on more than one port managed by the same IPC or IGC, the CLI uses the
value entered with the most-recent command for all the ports on the ICP or IGC.

Configuring numbered and named ACLs
When you configure ACLs, you can refer to the ACL by a numeric ID or by an alphanumeric name.
The commands to configure numbered ACLs are different from the commands for named ACLs:

• If you refer to the ACL by a numeric ID, you can use 1 – 99 for a standard ACL or 100 – 199 for
an extended ACL. This document refers to this ACL as numbered ACL.

• If you refer to the ACL by a name, you specify whether the ACL is a standard ACL or an extended
ACL, then specify the name. This document refers to this ACL type as named ACL.
You can configure up to 100 standard numbered IP ACLs and 100 extended numbered IP ACLs. You
also can configure up to 100 standard named ACLs and 100 extended named ACLs by number.
Regardless of how many ACLs you have, the device can have a maximum of 4096 ACL entries,
associated with the ACLs in any combination.

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Configuring standard numbered ACLs
This section describes how to configure standard numbered ACLs with numeric IDs:

• For configuration information on named ACLs, refer to “Configuring standard or extended
named ACLs” on page 62.

• For configuration information on extended ACLs, refer to “Configuring extended numbered
ACLs” on page 56.
Standard ACLs permit or deny packets based on source IP address. You can configure up to 99
standard ACLs. There is no limit to the number of ACL entries an ACL can contain except for the
system-wide limitation. For the number of ACL entries supported on a device, refer to “ACL IDs and
entries” on page 52.
To configure a standard ACL and apply it to outgoing traffic on port 1/1, enter the following
commands.
ServerIronADX(config)# access-list 1 deny host 209.157.22.26
ServerIronADX(config)# access-list 1 deny 209.157.29.12
ServerIronADX(config)# access-list 1 deny host IPHost1
ServerIronADX(config)# access-list 1 permit any
ServerIronADX(config)# int eth 1/1
ServerIronADX(config-if-1/1)# ip access-group 1 in
ServerIronADX(config)# write memory

The commands in this example configure an ACL to deny packets from three source IP addresses
from being forwarded on port 1/1. The last ACL entry in this ACL permits all packets that are not
explicitly denied by the first three ACL entries.

Standard ACL syntax
Syntax: [no] access-list  deny | permit  |  
or
Syntax: [no] access-list  deny | permit / | 
Syntax: [no] access-list  deny | permit host  | 
Syntax: [no] access-list  deny | permit any
Syntax: [no] ip access-group  in | out
The  parameter is the access list number and can be from 1 – 99.
The deny | permit parameter indicates whether packets that match a policy in the access list are
denied (dropped) or permitted (forwarded).
The  parameter specifies the source IP address. Alternatively, you can specify the host
name.

NOTE

To specify the host name instead of the IP address, the host name must be configured using the
Brocade device’s DNS resolver. To configure the DNS resolver name, use the ip dns server-address…
command at the global CONFIG level of the CLI.

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The  parameter specifies the mask value to compare against the host address specified
by the  parameter. The  is a four-part value in dotted-decimal notation (IP
address format) consisting of ones and zeros. Zeros in the mask mean the packet’s source address
must match the . Ones mean any value matches. For example, the  and
 values 209.157.22.26 0.0.0.255 mean that all hosts in the Class C sub-net
209.157.22.x match the policy.
If you prefer to specify the wildcard (mask value) in CIDR format, you can enter a forward slash after
the IP address, then enter the number of significant bits in the mask. For example, you can enter
the CIDR equivalent of “209.157.22.26 0.0.0.255” as “209.157.22.26/24”. The CLI automatically
converts the CIDR number into the appropriate ACL mask (where zeros instead of ones are the
significant bits) and changes the non-significant portion of the IP address into ones. For example, if
you specify 209.157.22.26/24 or 209.157.22.26 0.0.0.255, then save the changes to the
startup-config file, the value appears as 209.157.22.0/24 (if you have enabled display of sub-net
lengths) or 209.157.22.0 0.0.0.255 in the startup-config file.
If you enable the software to display IP sub-net masks in CIDR format, the mask is saved in the file
in
“/” format. To enable the software to display the CIDR masks, enter the ip
show-subnet-length command at the global CONFIG level of the CLI. You can use the CIDR format to
configure the ACL entry regardless of whether the software is configured to display the masks in
CIDR format.

NOTE

If you use the CIDR format, the ACL entries appear in this format in the running-config and
startup-config files, but are shown with sub-net mask in the display produced by the show ip
access-list command.
The host  |  parameter lets you specify a host IP address or name. When
you use this parameter, you do not need to specify the mask. A mask of all zeros (0.0.0.0) is
implied.
The any parameter configures the policy to match on all host addresses.
The in | out parameter specifies whether the ACL applies to incoming traffic or outgoing traffic on
the interface to which you apply the ACL. You can apply the ACL to an Ethernet port. Note that the
out option is not supported in the rule-based ACL mode.

Configuring extended numbered ACLs
This section describes how to configure extended numbered ACLs:

• For configuration information on named ACLs, refer to “Configuring numbered and named
ACLs” on page 54.

• For configuration information on standard ACLs, refer to “Configuring standard numbered
ACLs” on page 55.
Extended ACLs let you permit or deny packets based on the following information:

•
•
•
•
•

56

IP protocol
Source IP address or host name
Destination IP address or host name
Source TCP or UDP port (if the IP protocol is TCP or UDP)
Destination TCP or UDP port (if the IP protocol is TCP or UDP)

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The IP protocol can be one of the following well-known names or any IP protocol number from 0 –
255:

•
•
•
•
•
•
•

Internet Control Message Protocol (ICMP)
Internet Group Management Protocol (IGMP)
Internet Gateway Routing Protocol (IGRP)
Internet Protocol (IP)
Open Shortest Path First (OSPF)
Transmission Control Protocol (TCP)
User Datagram Protocol (UDP)

For TCP and UDP, you also can specify a comparison operator and port name or number. For
example, you can configure a policy to block web access to a specific website by denying all TCP
port 80 (HTTP) packets from a specified source IP address to the website’s IP address.
To configure an extended access list that blocks all Telnet traffic received on port 1/1 from IP host
209.157.22.26, enter the following commands.
ServerIronADX(config)# access-list 101 deny tcp host 209.157.22.26 any eq telnet l
ServerIronADX(config)# access-list 101 permit ip any any
ServerIronADX(config)# int eth 1/1
ServerIronADX(config-if-1/1)# ip access-group 101 in
ServerIronADX(config)# write memory

Here is another example of commands for configuring an extended ACL and applying it to an
interface. These examples show many of the syntax choices.
ServerIronADX(config)#
209.157.21.0/24
ServerIronADX(config)#
ServerIronADX(config)#
ServerIronADX(config)#
209.157.22.1
ServerIronADX(config)#
ServerIronADX(config)#

access-list 102 perm icmp 209.157.22.0/24
access-list 102 deny igmp host rkwong 209.157.21.0/24
access-list 102 deny igrp 209.157.21.0/24 host rkwong
access-list 102 deny ip host 209.157.21.100 host
access-list 102 deny ospf any any
access-list 102 permit ip any any

The first entry permits ICMP traffic from hosts in the 209.157.22.x network to hosts in the
209.157.21.x network.
The second entry denies IGMP traffic from the host device named “rkwong” to the 209.157.21.x
network.
The third entry denies IGRP traffic from the 209.157.21.x network to the host device named
“rkwong”.
The fourth entry denies all IP traffic from host 209.157.21.100 to host 209.157.22.1.
The fifth entry permits all packets that are not explicitly denied by the other entries. Without this
entry, the ACL would deny all incoming or outgoing IP traffic on the ports to which you assign the
ACL.
The following commands apply ACL 102 to the incoming traffic on port 1/2 and to the incoming
traffic on port 4/3.

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ServerIronADX(config)# int eth 1/2
ServerIronADX(config-if-1/2)# ip access-group 102 in
ServerIronADX(config-if-1/2)# exit
ServerIronADX(config)# int eth 4/3
ServerIronADX(config-if-4/3)# ip access-group 102 in
ServerIronADX(config)# write memory

Here is another example of an extended ACL.
ServerIronADX(config)#
ServerIronADX(config)#
209.157.22.0/24
ServerIronADX(config)#
telnet neq 5
ServerIronADX(config)#
range 7 8
ServerIronADX(config)#

access-list 103 deny tcp 209.157.21.0/24 209.157.22.0/24
access-list 103 deny tcp 209.157.21.0/24 eq ftp
access-list 103 deny tcp 209.157.21.0/24 209.157.22.0/24 lt
access-list 103 deny udp any range 5 6 209.157.22.0/24
access-list 103 permit ip any any

The first entry in this ACL denies TCP traffic from the 209.157.21.x network to the 209.157.22.x
network.
The second entry denies all FTP traffic from the 209.157.21.x network to the 209.157.22.x
network.
The third entry denies TCP traffic from the 209.157.21.x network to the 209.157.22.x network, if
the TCP port number of the traffic is less than the well-known TCP port number for Telnet (23), and
if the TCP port is not equal to 5. Thus, TCP packets whose TCP port numbers are 5 or are greater
than 23 are allowed.
The fourth entry denies UDP packets from any source to the 209.157.22.x network, if the UDP port
number from the source network is 5 or 6 and the destination UDP port is 7 or 8.
The fifth entry permits all packets that are not explicitly denied by the other entries. Without this
entry, the ACL would deny all incoming or outgoing IP traffic on the ports to which you assign the
ACL.
The following commands apply ACL 103 to the incoming traffic on ports 2/1 and 2/2.
ServerIronADX(config)# int eth 2/1
ServerIronADX(config-if-2/1)# ip access-group 103 in
ServerIronADX(config-if-2/1)# exit
ServerIronADX(config)# int eth 2/2
ServerIronADX(config-if-2/2)# ip access-group 103 in
ServerIronADX(config)# write memory

Extended ACL syntax
Use the following syntax for configuring extended numbered ACLs.
Syntax: [no] access-list  deny | permit   | 
 [ ]  | 
[ |  |  ] 
[ ] [established] [precedence  | ]
[tos  | ] [ip-pkt-len ]
Syntax: [no] access-list  deny | permit host  any any
Syntax: [no] ip access-group  in | out

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The  parameter indicates the ACL number and be from 100 – 199 for an extended ACL.
The deny | permit parameter indicates whether packets that match the policy are dropped or
forwarded.
The  parameter indicates the type of IP packet you are filtering. You can specify a
well-known name for any protocol whose number is less than 255. For other protocols, you must
enter the number. Enter “?” instead of a protocol to list the well-known names recognized by the
CLI.
The  |  parameter specifies the source IP host for the policy. If you want
the policy to match on all source addresses, enter any.
The  parameter specifies the portion of the source IP host address to match against.
The  is a four-part value in dotted-decimal notation (IP address format) consisting of
ones and zeros. Zeros in the mask mean the packet’s source address must match the .
Ones mean any value matches. For example, the  and  values
209.157.22.26 0.0.0.255 mean that all hosts in the Class C sub-net 209.157.22.x match the
policy.
If you prefer to specify the wildcard (mask value) in Classless Interdomain Routing (CIDR) format,
you can enter a forward slash after the IP address, then enter the number of significant bits in the
mask. For example, you can enter the CIDR equivalent of “209.157.22.26 0.0.0.255” as
“209.157.22.26/24”. The CLI automatically converts the CIDR number into the appropriate ACL
mask (where zeros instead of ones are the significant bits) and changes the non-significant portion
of the IP address into zeros. For example, if you specify 209.157.22.26/24 or 209.157.22.26
0.0.0.255, then save the changes to the startup-config file, the value appears as 209.157.22.0/24
(if you have enabled display of sub-net lengths) or 209.157.22.0 0.0.0.255 in the startup-config
file.
If you enable the software to display IP sub-net masks in CIDR format, the mask is saved in the file
in “/” format. To enable the software to display the CIDR masks, enter the ip
show-subnet-length command at the global CONFIG level of the CLI. You can use the CIDR format to
configure the ACL entry regardless of whether the software is configured to display the masks in
CIDR format.

NOTE

If you use the CIDR format, the ACL entries appear in this format in the running-config and
startup-config files, but are shown with sub-net mask in the display produced by the show ip
access-list command.
The  |  parameter specifies the destination IP host for the policy. If
you want the policy to match on all destination addresses, enter any.
The  |  parameter specifies the ICMP protocol type.

• This parameter applies only if you specified icmp as the  value.
• If you use this parameter, the ACL entry is sent to the CPU for processing.
• If you do not specify a message type, the ACL applies to all types of ICMP messages.
The  parameter can be a value from 0 – 255.
The  parameter can have one of the following values, depending on the software
version the device is running:

• any-icmp-type
• echo

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•
•
•
•
•
•
•
•
•
•
•
•
•

echo-reply
information-request
log
mask-reply
mask-request
parameter-problem
redirect
source-quench
time-exceeded
timestamp-reply
timestamp-request
unreachable


The  parameter specifies a comparison operator for the TCP or UDP port number. This
parameter applies only when you specify tcp or udp as the IP protocol. For example, if you are
configuring an entry for HTTP, specify tcp eq http. You can enter one of the following operators:

• eq – The policy applies to the TCP or UDP port name or number you enter after eq.
• gt – The policy applies to TCP or UDP port numbers greater than the port number or the
numeric equivalent of the port name you enter after gt.

• lt – The policy applies to TCP or UDP port numbers that are less than the port number or the
numeric equivalent of the port name you enter after lt.

• neq – The policy applies to all TCP or UDP port numbers except the port number or port name
you enter after neq.

• range – The policy applies to all TCP or UDP port numbers that are between the first TCP or
UDP port name or number and the second one you enter following the range parameter. The
range includes the port names or numbers you enter. For example, to apply the policy to all
ports between and including 23 (Telnet) and 53 (DNS), enter the following: range 23 53. The
first port number in the range must be lower than the last number in the range.

• established – This operator applies only to TCP packets. If you use this operator, the policy
applies to TCP packets that have the ACK (Acknowledgment) or RST (Reset) bits set on (set to
“1”) in the Control Bits field of the TCP packet header. Thus, the policy applies only to
established TCP sessions, not to new sessions. Refer to Section 3.1, “Header Format”, in RFC
793 for information about this field.

NOTE

This operator applies only to destination TCP ports, not source TCP ports.
The  parameter specifies the TCP or UDP port number or well-known name. You can
specify a well-known name for any application port whose number is less than 1024. For other
application ports, you must enter the number. Enter “?” instead of a port to list the well-known
names recognized by the CLI.
The in | out parameter specifies whether the ACL applies to incoming traffic or outgoing traffic on
the interface to which you apply the ACL. You can apply the ACL to an Ethernet port.

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NOTE

The out option is not supported in the rule-based ACL mode.
The precedence  |  parameter of the ip access-list command specifies the IP
precedence. The precedence option for of an IP packet is set in a three-bit field following the
four-bit header-length field of the packet’s header. You can specify one of the following:

• critical or 5 – The ACL matches packets that have the critical precedence. If you specify the
option number instead of the name, specify number 5.

• flash or 3 – The ACL matches packets that have the flash precedence. If you specify the option
number instead of the name, specify number 3.

• flash-override or 4 – The ACL matches packets that have the flash override precedence. If you
specify the option number instead of the name, specify number 4.

• immediate or 2 – The ACL matches packets that have the immediate precedence. If you
specify the option number instead of the name, specify number 2.

• internet or 6 – The ACL matches packets that have the internetwork control precedence. If you
specify the option number instead of the name, specify number 6.

• network or 7 – The ACL matches packets that have the network control precedence. If you
specify the option number instead of the name, specify number 7.

• priority or 1 – The ACL matches packets that have the priority precedence. If you specify the
option number instead of the name, specify number 1.

• routine or 0 – The ACL matches packets that have the routine precedence. If you specify the
option number instead of the name, specify number 0.
The tos  |  parameter of the ip access-list command specifies the IP ToS. You can
specify one of the following:

• max-reliability or 2 – The ACL matches packets that have the maximum reliability ToS. The
decimal value for this option is 2.

• max-throughput or 4 – The ACL matches packets that have the maximum throughput ToS. The
decimal value for this option is 4.

• min-delay or 8 – The ACL matches packets that have the minimum delay ToS. The decimal
value for this option is 8.

• min-monetary-cost or 1 – The ACL matches packets that have the minimum monetary cost
ToS. The decimal value for this option is 1.

NOTE

This value is not supported on 10 Gigabit Ethernet modules.

• normal or 0 – The ACL matches packets that have the normal ToS. The decimal value for this
option is 0.

•  – A number from 0 – 15 that is the sum of the numeric values of the options you want.
The ToS field is a four-bit field following the Precedence field in the IP header. You can specify
one or more of the following. To select more than one option, enter the decimal value that is
equivalent to the sum of the numeric values of all the ToS options you want to select. For
example, to select the max-reliability and min-delay options, enter number 10. To select all
options, select 15.
The ip-pkt-len  parameter filters ICMP packets based on the IP packet length. The device
uses the  to match the total length field in the IP header of ICMP packets. You can specify a
value from 1 – 65535.

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NOTE

This parameter applies only if you specified icmp as the  value.
The log parameter enables SNMP traps and Syslog messages for packets denied by the ACL.
You can enable logging on ACLs and filters that support logging even when the ACLs and filters are
already in use. To do so, re-enter the ACL or filter command and add the log parameter to the end
of the ACL or filter. The software replaces the ACL or filter command with the new one. The new ACL
or filter, with logging enabled, takes effect immediately.

Configuring standard or extended named ACLs
To configure a named IP ACL, use the following CLI method.
The commands for configuring named ACL entries are different from the commands for configuring
numbered ACL entries. The command to configure a numbered ACL is access-list. The command
for configuring a named ACL is ip access-list. In addition, when you configure a numbered ACL
entry, you specify all the command parameters on the same command. When you configure a
named ACL, you specify the ACL type (standard or extended) and the ACL number with one
command, which places you in the configuration level for that ACL. Once you enter the
configuration level for the ACL, the command syntax is the same as the syntax for numbered ACLs.
The following examples show how to configure a named standard ACL entry and a named extended
ACL entry.
Configuration example for standard ACL
To configure a named standard ACL entry, enter commands such as the following.
ServerIronADX(config)# ip access-list standard Net1
ServerIronADX(config-std-nacl)# deny host 209.157.22.26 log
ServerIronADX(config-std-nacl)# deny 209.157.29.12 log
ServerIronADX(config-std-nacl)# deny host IPHost1 log
ServerIronADX(config-std-nacl)# permit any
ServerIronADX(config-std-nacl)# exit
ServerIronADX(config)# int eth 1/1
ServerIronADX(config-if-1/1)# ip access-group Net1 out

The commands in this example configure a standard ACL named “Net1”. The entries in this ACL
deny packets from three source IP addresses from being forwarded on port 1/1. Since the implicit
action for an ACL is “deny”, the last ACL entry in this ACL permits all packets that are not explicitly
denied by the first three ACL entries. For an example of how to configure the same entries in a
numbered ACL, refer to “Configuring standard numbered ACLs” on page 55.
Notice that the command prompt changes after you enter the ACL type and name. The “std” in the
command prompt indicates that you are configuring entries for a standard ACL. For an extended
ACL, this part of the command prompt is “ext“. The “nacl” indicates that are configuring a named
ACL.
Syntax: ip access-list extended | standard  | 
The extended | standard parameter indicates the ACL type.

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The  parameter is the ACL name. You can specify a string of up to 256 alphanumeric
characters. You can use blanks in the ACL name if you enclose the name in quotation marks (for
example, “ACL for Net1”). The  parameter allows you to specify an ACL number if you prefer.
If you specify a number, you can specify from 1 – 99 for standard ACLs or 100 – 199 for extended
ACLs.

NOTE

For convenience, the software allows you to configure numbered ACLs using the syntax for named
ACLs. The software also still supports the older syntax for numbered ACLs. Although the software
allows both methods for configuring numbered ACLs, numbered ACLs are always formatted in the
startup-config and running-config files in using the older syntax, as follows.
access-list
access-list
access-list
access-list

1 deny host 209.157.22.26
1 deny 209.157.22.0 0.0.0.255
1 permit any
101 deny tcp any any eq http

The options at the ACL configuration level and the syntax for the ip access-group command are the
same for numbered and named ACLs and are described in “Configuring standard numbered ACLs”
on page 55.
Configuration example for extended ACL
To configure a named extended ACL entry, enter commands such as the following.
ServerIronADX(config)# ip access-list extended “block Telnet”
ServerIronADX(config-ext-nacl)# deny tcp host 209.157.22.26 any eq telnet
ServerIronADX(config-ext-nacl)# permit ip any any
ServerIronADX(config-ext-nacl)# exit
ServerIronADX(config)# int eth 1/1
ServerIronADX(config-if-1/1)# ip access-group “block Telnet” in

The options at the ACL configuration level and the syntax for the ip access-group command are the
same for numbered and named ACLs and are described in “Configuring extended numbered ACLs”
on page 56.

Displaying ACL definitions
To display the ACLs configured on a device, use the show ip access-lists command. Here is an
example.
ServerIronADX(config)# show ip access-lists
Extended IP access list 101
deny tcp host 209.157.22.26 host 209.157.22.26 eq http

Syntax: show ip access-lists []
The show access-list and show ip access-list commands have been updated to display ACL entries
with line numbers.
Numbered ACL
For a numbered ACL, you can enter a command such as the following.

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ServerIronADX(config)# show access-list 99 3
Standard IP access-list 99
deny 10.10.10.1
deny 192.168.1.13
permit any

Syntax: show access-list  []
Enter the ACL’ number for the  parameter.
Determine from which line you want the displayed information to begin and enter that number for
the  parameter.
Named ACL
For a named ACL, enter a command such as the following.
ServerIronADX(config)# ip show access-list standard melon 3
Standard IP access-list melon
deny host 5.6.7.8
deny 192.168.12.3
permit any

Syntax: show ip access-list  |  []
Enter the ACL name for the  parameter or the ACL’s number for .
Determine from which line you want the displayed information to begin and enter that number for
the  parameter.

Displaying ACLs using keywords
You limit the displayed ACL entries to those that contain a specified keyword.

Numbered ACL
You may have the following numbered ACL.
ServerIronADX(config)# show access-list 99
Standard IP access-list 99
deny host 1.2.3.4
permit host 5.6.7.8
permit host 5.10.11.12
permit any

If you want to display ACL entries beginning with the entry that contains the keyword “5” enter the
following command.
ServerIronADX(config)# show access-list 99 | begin 5
Standard IP access-list 99
permit host 5.6.7.8
permit host 5.10.11.12
permit any

Since the second entry is the first entry that contains the keyword “5”, the display begins with line
2.
If you want to display only the ACL entries that contain the keyword “5” enter the following
command.

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ServerIronADX(config)#show access-list 99 | include 5
Standard IP access-list 99
permit host 5.6.7.8
permit host 5.10.11.12

The second and third entries in the ACL contain the keyword “5” and are displayed in the show
access-list.
If you want to exclude ACL entries that contain a keyword from the show access-list display, enter
the following command.
ServerIronADX(config)# show access-list 99 | exclude 5
Standard IP access-list 99
deny host 1.2.3.4
permit any

The second and third ACL entries are left out from the display.
Syntax: show access-list  | begin | exclude | include 
Enter the ACL number for the  parameter.
Use the | operator to indicate a keyword.
Enter the begin  parameter to start the display beginning with the first line containing
the text that matches the keyword. For example, if you enter begin Total, the displayed
information begins with the line containing the word “Total”.
Enter the exclude  parameter to exclude any lines containing text that match the
keyword. For example, if you enter exclude Total, any line containing the word “Total” is
excluded from the display.
Enter the include  display only those lines containing text that match the keyword. For
example, if you enter include Total, any line containing the word “Total” is included in the
display.

Named ACLs
You may have the following numbered ACL.
ServerIronADX(config)# show access-list melon
Standard IP access-list melon
deny host 1.2.3.4
permit host 5.6.7.8
permit host 5.10.11.12
permit any

If you want to display ACL entries beginning with the entry that contains the keyword “5” enter the
following command.
ServerIronADX(config)# show access-list melon | begin 5
Standard IP access-list melon
permit host 5.6.7.8
permit host 5.10.11.12
permit any

Since the second entry is the first entry that contains the keyword “5”, the display begins with line
2.
If you want to display only the ACL entries that contain the keyword “5” enter the following
command.

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ServerIronADX(config)# show access-list melon | include 5
Standard IP access-list melon
permit host 5.6.7.8
permit host 5.10.11.12

The second and third entries in the ACL contain the keyword “5” and are displayed in the show
access-list.
If you want to exclude ACL entries that contain a keyword from the show access-list display, enter
the following command.
ServerIronADX(config)# show access-list melon | exclude 5
Standard IP access-list melon
deny host 1.2.3.4
permit any

The second and third ACL entries are left out from the display.
Syntax: show ip access-list  | begin | exclude | include 
Enter the ACL’s number for the  parameter.
Use the | operator to indicate a keyword.
Enter the begin  parameter to start the display beginning with the first line containing
text that matches the keyword. For example, if you enter begin Total, the displayed information
begins with the line containing the word “Total”.
Enter the exclude  parameter to exclude any lines containing text that match the
keyword. For example, if you enter exclude Total, any line containing the word “Total” is excluded
from the display.
Enter the include  display only those lines containing text that match the keyword. For
example, if you enter include Total, any line containing the word “Total” is included in the display.
If ACL entries, for both numbered and named ACLs, have remarks, the display
will also include the remarks if they contain characters that match the
specified keywords. For example, ACL 99 might contain the following entries:
ServerIronADX(config)# show access-list 99
Standard IP access-list 99
ACL Remark: Deny Building A
deny host 1.2.3.4
Permit First Floor Users
permit host 5.6.7.8
deny host 5.10.11.12
permit any
To show all entries containing the keyword “deny” you obtain the following
output:
ServerIronADX(config)#show access-list 99 | include deny
Standard IP access-list 99
ACL Remark: Deny Building A
deny host 1.2.3.4
deny host 5.10.11.12

NOTE
All lines with the keyword “deny”, including remarks are included in the display.

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Modifying ACLs
When you use the Brocade device’s CLI to configure any ACL, the software places the ACL entries in
the ACL in the order you enter them. For example, if you enter the following entries in the order
shown below, the software always applies the entries to traffic in the same order.
ServerIronADX(config)# access-list 1 deny 209.157.22.0/24
ServerIronADX(config)# access-list 1 permit 209.157.22.26

If a packet matches the first ACL entry in this ACL and is therefore denied, the software does not
compare the packet to the remaining ACL entries. In this example, packets from host
209.157.22.26 will always be dropped, even though packets from this host match the second
entry.
You can use the CLI to reorder entries within an ACL by individually removing the ACL entries and
then re-adding them. To use this method, enter “no” followed by the command for an ACL entry,
and repeat this for each ACL entry in the ACL you want to edit. After removing all the ACL entries
from the ACL, re-add them.
This method works well for small ACLs such as the example above, but can be impractical for ACLs
containing many entries. Therefore, Brocade devices provide an alternative method. The alternative
method lets you upload an ACL list from a TFTP server and replace the ACLs in the device’s
running-config file with the uploaded list. Thus, to change an ACL, you can edit the ACL on the file
server, then upload the edited ACL to the device. You then can save the changed ACL to the
device’s startup-config file.
ACL lists contain only the ACL entries themselves, not the assignments of ACLs to interfaces. You
must assign the ACLs on the device itself.

NOTE

The only valid commands that are valid in the ACL list are the access-list and end commands. The
Brocade device ignores other commands in the file.
To modify an ACL by configuring an ACL list on a file server.
1. Use a text editor to create a new text file. When you name the file, use 8.3 format (up to eight
characters in the name and up to three characters in the extension).

NOTE

Make sure the Brocade device has network access to the TFTP server.
2. Optionally, clear the ACL entries from the ACLs you are changing by placing commands such as
the following at the top of the file.
no access-list 1
no access-list 101

When you load the ACL list into the device, the software adds the ACL entries in the file after
any entries that already exist in the same ACLs. Thus, if you intend to entirely replace an ACL,
you must use the no access-list  command to clear the entries from the ACL before the
new ones are added.
3. Place the commands to create the ACL entries into the file. The order of the separate ACLs
does not matter, but the order of the entries within each ACL is important. The software applies
the entries in an ACL in the order they are listed within the ACL. Here is an example of some
ACL entries.

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access-list
access-list
access-list
access-list

1 deny host 209.157.22.26 log
1 deny 209.157.22.0 0.0.0.255 log
1 permit any
101 deny tcp any any eq http log

The software will apply the entries in ACL 1 in the order shown and stop at the first match.
Thus, if a packet is denied by one of the first three entries, the packet will not be permitted by
the fourth entry, even if the packet matches the comparison values in this entry.
4. Enter the command end on a separate line at the end of the file. This command indicates to
the software that the entire ACL list has been read from the file.
5. Save the text file.
6. On the Brocade device, enter the following command at the Privileged EXEC level of the CLI.
copy tftp running-config  

NOTE

This command will be unsuccessful if you place any commands other than access-list and end
(at the end only) in the file. These are the only commands that are valid in a file you load using
the copy tftp running-config… command.
7.

To save the changes to the device’s startup-config file, enter the following command at the
Privileged EXEC level of the CLI.
write memory

Here is a complete example of an ACL configuration file.
no access-list 1
no access-list 101
access-list 1 deny host 209.157.22.26 log
access-list 1 deny 209.157.22.0 0.0.0.255 log
access-list 1 permit any
access-list 101 deny tcp any any eq http log
end

NOTE
Do not place other commands in the file. The Brocade device reads only the ACL information in the
file and ignores other commands, including ip access-group commands. To assign ACLs to
interfaces, use the CLI.

Displaying a list of ACL entries
The show access-list and show ip access-list commands displays ACL entries with line numbers.

Numbered ACLs
To display the contents of numbered ACLs, enter a command such as the following.
ServerIronADX# show access-list 99
Standard IP access list 99
deny host 1.2.4.5
deny host 5.6.7.8
permit any

Syntax: show access-list  | all

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Named ACLs
To display the contents of named ACLs, enter a command such as the following.
ServerIronADX# show ip access-list melon
Standard IP access list melon
deny host 1.2.4.5
deny host 5.6.7.8
permit any

Syntax: show ip access-list  | 

Applying an ACLs to interfaces
Configuration examples in the section “Configuring numbered and named ACLs” on page 54 show
that you apply ACLs to interfaces using the ip access-group command. This section present
additional information about applying ACLs to interfaces.

Reapplying modified ACLs
If you make an ACL configuration change, you must reapply the ACLs to their interfaces to place the
change into effect.
An ACL configuration change includes any of the following:

• Adding, changing, or removing an ACL or an entry in an ACL
• Changing a PBR policy
To reapply ACLs following an ACL configuration change, enter the following command at the global
CONFIG level of the CLI.
ServerIronADX(config)# ip rebind-acl all

Syntax: [no] ip rebind-acl  |  | all

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ACL logging

ACL logging
You may want the software to log entries for ACLs in the syslog. This section present the how
logging is processed by rule-based ACLs.
Rule-based ACLs do not support the log option. Even when rule-based ACLs are enabled, if an ACL
entry has the log option, traffic that matches that ACL is sent to the CPU for processing. Depending
on how many entries have the log option and how often packets match those entries, ACL
performance can be affected.
If your configuration already contains ACLs that you want to use with rule-based ACLs, but some of
the ACLs contain the log option, the software changes the ACL mode to flow-based for the traffic
flows that match the ACL. Changing the mode to flow-based enables the device to send the
matching flows to the CPU for processing. This is required because the CPU is needed to generate
the Syslog message.
You can globally disable ACL logging without the need to remove the log option from each ACL
entry. When you globally disable ACL logging, the ACL entries remain unchanged but the log option
is ignored and the ACL can use the rule-based ACL mode. This enables you to use the ACLs in the
rule-based ACL mode. You also can configure the device to copy traffic that is denied by a
rule-based ACL to an interface. This option allows you to monitor the denied traffic without sending
the traffic to the CPU.
To globally disable ACL logging, enter the following command at the global CONFIG level of the CLI.
ServerIronADX(config)# ip access-list disable-log-to-cpu

Syntax: [no] ip access-list disable-log-to-cpu
To re-enable ACL logging, enter the following command.
ServerIronADX(config)# no ip access-list disable-log-to-cpu

Syslog message for changed ACL mode
If the device changes the ACL mode from rule-based to flow-based, the device generates one of the
following Syslog notification messages:

• ACL insufficient L4 session resource, using flow based ACL instead.
• ACL exceed max DMA L4 cam resource, using flow based ACL instead. Refer to “Specifying the
maximum number of CAM entries for rule-based ACLs” on page 54.

• ACL insufficient L4 cam resource, using flow based ACL instead.

Copying denied traffic to a mirror port for monitoring
Although rule-based ACLs do not support ACL logging, you nonetheless can monitor the traffic
denied by rule-based ACLs. To do so, attach a protocol analyzer to a port and enable the device to
redirect traffic denied by ACLs to that port.
To redirect traffic denied by ACLs, enter the following command at the interface configuration level.
ServerIronADX(config-if-1/1)# ip access-group redirect-deny-to-interf

Syntax: [no] ip access-group redirect-deny-to-interf
Enter the command on the port to which you want the denied traffic to be copied.

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NOTE

The software requires that an ACL has already been applied to the interface.
When you enable redirection, the deny action of the ACL entry is still honored. Traffic that matches
the ACL is not forwarded.

Displaying ACL log entries
The first time an entry in an ACL permits or denies a packet and logging is enabled for that entry,
the software generates a Syslog message and an SNMP trap. Messages for packets permitted or
denied by ACLs are at the warning level of the Syslog.
When the first Syslog entry for a packet permitted or denied by an ACL is generated, the software
starts an ACL timer. After this, the software sends Syslog messages every one to ten minutes,
depending on the value of the timer interval. If an ACL entry does not permit or deny any packets
during the timer interval, the software does not generate a Syslog entry for that ACL entry.

NOTE

For an ACL entry to be eligible to generate a Syslog entry for permitted or denied packets, logging
must be enabled for the entry. The Syslog contains entries only for the ACL entries that deny packets
and have logging enabled.
To display Syslog entries, enter the following command from any CLI prompt.
ServerIronADX(config)# show log
Syslog logging: enabled (0 messages dropped, 0 flushes, 0 overruns)
Buffer logging: level ACDMEINW, 38 messages logged
level code: A=alert C=critical D=debugging M=emergency E=error
I=informational N=notification W=warning
Log Buffer (50 entries):
21d07h02m40s:warning:list 101 denied tcp 209.157.22.191(0)(Ethernet 4/18
0010.5a1f.77ed) -> 198.99.4.69(http), 1 event(s)
00d07h03m30s:warning:list 101 denied tcp 209.157.22.26(0)(Ethernet 4/18
0010.5a1f.77ed) -> 198.99.4.69(http), 1 event(s)
00d06h58m30s:warning:list 101 denied tcp 209.157.22.198(0)(Ethernet 4/18
0010.5a1f.77ed) -> 198.99.4.69(http), 1 event(s)

In this example, the two-line message at the bottom is the first entry, which the software
immediately generates the first time an ACL entry permits or denies a packet. In this case, an entry
in ACL 101 denied a packet. The packet was a TCP packet from host 209.157.22.198 and was
destined for TCP port 80 (HTTP) on host 198.99.4.69.
When the software places the first entry in the log, the software also starts the five-minute timer for
subsequent log entries. Thus, five minutes after the first log entry, the software generates another
log entry and SNMP trap for denied packets.
In this example, the software generates the second log entry five minutes later.
The time stamp for the third entry is much later than the time stamps for the first two entries. In
this case, no ACLs denied packets for a very long time. In fact, since no ACLs denied packets during
the five-minute interval following the second entry, the software stopped the ACL log timer. The
software generated the third entry as soon as the ACL denied a packet. The software restarted the
five-minute ACL log timer at the same time. As long as at least one ACL entry permits or denies a
packet, the timer continues to generate new log entries and SNMP traps every five minutes.

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Dropping all fragments that exactly match a flow-based ACL

You can also configure the maximum number of ACL-related log entries that can be added to the
system log over a one-minute period. For example, to limit the device to 100 ACL-related syslog
entries per minute.
ServerIronADX(config)# max-acl-log-num 100

Syntax: [no] max-acl-log-num 
You can specify a number between 0 – 4096. The default is 256. Specifying 0 disables all ACL
logging.

Displaying ACL statistics for flow-based ACLs
To display ACL statistics for flow-based ACLs, enter the following command.
ServerIronADX(config)# show ip acl-traffic
ICMP inbound packets received 400
ICMP inbound packets permitted 200
ICMP inbound packets denied 200

Syntax: show ip acl-traffic
The command lists a separate set of statistics for each of the following IP protocols:

•
•
•
•
•
•
•
•

ICMP
IGMP
IGRP
IP
OSPF
TCP
UDP
Protocol number, if an ACL is configured for a protocol not listed above

For TCP and UDP, a separate set of statistics is listed for each application port.

Clearing flow-based ACL statistics
To clear the ACL statistics, enter the following command at the Privileged EXEC level of the CLI.
ServerIronADX(config)# clear ip acl-traffic

Syntax: clear ip acl-traffic

Dropping all fragments that exactly match a flow-based ACL
For a packet fragment that is sent to the CPU for processing, the device compares the fragment’s
source and destination IP addresses against the interface’s ACL entries. By default, if the
fragment’s source and destination IP addresses exactly match an ACL entry that also has Layer 4
information (source and destination TCP or UDP application ports), the device permits or denies the
fragment according to the ACL.

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On an individual interface basis, you can configure an IronCore device to automatically drop a
fragment whose source and destination IP addresses exactly match an ACL entry that has Layer 4
information, even if that ACL entry’s action is permit. To do so, enter the following command at the
configuration level for an interface.
ServerIronADX(config-if-1/1)# ip access-group frag deny

Syntax: [no] ip access-group frag deny

Clearing the ACL statistics
Statistics on the ACL account report can be cleared:

• When a software reload occurs
• When the ACL is bound to or unbound from an interface
• When you enter the clear access-list command, as in the following example.
ServerIronADX(config)# clear access-list all

Syntax: clear access-list all | ethernet /
Enter all to clear all statistics for all ACLs.
Use ethernet / to clear statistics for ACLs a physical port.

Enabling ACL filtering of fragmented packets
Filtering fragmented packets for rule-based ACLs
By default, when a rule-based ACL is applied to a port, the port will use the ACL to permit or deny
the first fragment of a fragmented packet, but forward subsequent fragments of the same packet
in hardware. Generally, denying the first fragment of a packet is sufficient, since a transaction
cannot be completed without the entire packet.

NOTE

The fragmentation support described in this section applies only to rule-based ACLs.

NOTE

Enhanced fragment handling is not supported on 10 Gigabit Ethernet modules. By default, 10
Gigabit Ethernet modules also forward the first fragment instead of using the ACLs to permit or deny
the fragment.
For tighter control, you can enable CPU filtering of all packet fragments on a port. When you enable
CPU filtering, the port sends all the fragments of a fragmented packet to the CPU. The CPU then
permits or denies each fragment according to the ACL applied to the port. You can enable CPU
filtering of fragments on individual ports.
You also can configure the port to drop all packet fragments.
To enable CPU filtering of packet fragments on an individual port, enter commands such as the
following.
ServerIronADX(config)# interface ethernet 1/1
ServerIronADX(config-if-1/1)# ip access-group frag inspect

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Enabling ACL filtering of fragmented packets

Syntax: [no] ip access-group frag inspect | deny
The inspect | deny parameter specifies whether you want fragments to be sent to the CPU or
dropped:

• inspect – This option sends all fragments to the CPU.
• deny – This option begins dropping all fragments received by the port as soon as you enter the
command. This option is especially useful if the port is receiving an unusually high rate of
fragments, which can indicate a hacker attack.

Throttling the fragment rate
By default, when you enable CPU filtering of packet fragments, all fragments are sent to the CPU.
Normally, the fragment rate in a typical network does not place enough additional load on the CPU
to adversely affect performance. However, performance can be affected if the device receives a
very high rate of fragments. For example, a misconfigured server or a hacker can affect the
device’s performance by flooding the CPU with fragments.
You can protect against fragment flooding by specifying the maximum number of fragments the
device or an individual interface is allowed to send to the CPU in a one-second interval. If the device
or an interface receives more than the specified number of fragments in a one-second interval, the
device either drops or forwards subsequent fragments in hardware, depending on the action you
specify. In addition, the device starts a holddown timer and continues to either drop or forward
fragments until the holddown time expires.
The device also generates a Syslog message.
To specify the maximum fragment rate per second, enter commands such as the following.
ServerIronADX(config)# ip access-list frag-rate-on-system 15000 exceed-action
drop reset-interval 10
ServerIronADX(config)#ip access-list frag-rate-on-interface 5000 exceed-action
forward reset-interval 5

The first command sets the fragment threshold at 15,000 per second, for the entire device. If the
device receives more than 15,000 packet fragments in a one-second interval, the device takes the
specified action. The action specified with this command is to drop the excess fragments and
continue dropping fragments for a holddown time of ten minutes. After the ten minutes have
passed, the device starts sending fragments to the CPU again for processing.
The second command sets the fragment threshold at 5,000 for individual interfaces. If any
interface on the device receives more than 5,000 fragments in a one-second interval, the device
takes the specified action. In this case, the action is to forward the fragments in hardware without
filtering them. The device continues forwarding fragments in hardware for five minutes before
beginning to send fragments to the CPU again.
Both thresholds apply to the entire device. Thus, if an individual interface’s fragment threshold is
exceeded, the drop or forward action and the holddown time apply to all fragments received by the
device.
Syntax: [no] ip access-list frag-rate-on-system  exceed-action drop | forward reset-interval

and
Syntax: [no] ip access-list frag-rate-on-interface  exceed-action drop | forward reset-interval


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The  parameter specifies the maximum number of fragments the device or an individual
interface can receive and send to the CPU in a one-second interval.

• frag-rate-on-system – Sets the threshold for the entire device. The device can send to the CPU
only the number of fragments you specify per second, regardless of which interfaces the
fragments come in on. If the threshold is exceeded, the device takes the exceed action you
specify.

• frag-rate-on-interface – Sets the threshold for individual interfaces. If an individual interface
receives more than the specified maximum number of fragments, the device takes the exceed
action you specify.
The  parameter specifies the maximum number of fragments per second.

• For frag-rate-on-system, you can specify from 600 – 12800. The default is 6400.
• For frag-rate-on-interface, you can specify from 300 – 8000. The default is 4000.
The drop | forward parameter specifies the action to take if the threshold ( parameter) is
exceeded:

• drop – fragments are dropped without filtering by the ACLs
• forward – fragments are forwarded in hardware without filtering by the ACLs
The  parameter specifies the number of minutes the device will enforce the drop or forward
action after a threshold has been exceeded. You can specify from 1 – 30 minutes, for
frag-rate-on-system or frag-rate-on-interface.

Syslog messages for exceeded fragment thresholds
If a fragment threshold is exceeded, the device generates one of the following Syslog messages.

TABLE 4

Syslog messages for exceeded fragment threshold

Message level

Message

Explanation

Notification

ACL system fragment packet inspect rate
 exceeded

The  indicates the maximum rate
allowed.

Notification

ACL port fragment packet inspect rate 
exceeded on port 

The  indicates the maximum rate
allowed.
The  indicates the port.

Enabling hardware filtering for packets denied by flow-based ACLs
By default, packets denied by ACLs are filtered by the CPU. You can enable the device to create
CAM entries for packets denied by ACLs. This causes the filtering to occur in hardware instead of in
the CPU.
When you enable hardware filtering of denied packets, the first time the device filters a packet
denied by an ACL, the device sends the packet to the CPU for processing. The CPU also creates a
CAM entry for the denied packet. Subsequent packets with the same address information are
filtered using the CAM entry. The CAM entry ages out after two minutes if not used.
To enable hardware filtering of denied packets, enter the following command at the global CONFIG
level of the CLI.
ServerIronADX(config)# hw-drop-acl-denied-packet

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Enabling strict TCP or UDP mode for flow-based ACLs

Syntax: [no] hw-drop-acl-denied-packet

Enabling strict TCP or UDP mode for flow-based ACLs
By default, when you use ACLs to filter TCP or UDP traffic, the Brocade device does not compare all
TCP or UDP packets against the ACLs.
For TCP and UDP, the device first compares the source and destination information in a TCP control
packet or a UDP packet against entries in the session table. The session table contains forwarding
entries based on Layer 3 and Layer 4 information:

• If the session table contains a matching entry, the device forwards the packet, assuming that
the first packet the device received with the same address information was permitted by the
ACLs.

• If the session table does not contain a matching entry, the device sends the packet to the CPU,
where the software compares the packet against the ACLs. If the ACLs permit the packet
(explicitly by a permit ACL entry or implicitly by the absence of a deny ACL entry), the CPU
creates a session table entry for the packet’s forwarding information and forwards the packet.
For TCP, this behavior by default applies only to control packets, not to data packets. Control
packets include packet types such as SYN (Synchronization) packets, FIN (Finish) packets, and RST
(Reset) packets.
For tighter access or forwarding control, you can enable the device to perform strict TCP or UDP ACL
processing. The following sections describe the strict modes in more detail.

Enabling strict TCP mode
By default, when you use ACLs to filter TCP traffic, the Brocade device does not compare all TCP
packets against the ACLs. Instead, the device compares TCP control packets against the ACLs, but
not data packets. Control packets include packet types such as SYN (Synchronization) packets, FIN
(Finish) packets, and RST (Reset) packets.
In normal TCP operation, TCP data packets are present only if a TCP control session for the packets
also is established. For example, data packets for a session never occur if the TCP SYN for that
session is dropped. Therefore, by filtering the control packets, the Brocade device also implicitly
filters the data packets associated with the control packets. This mode of filtering optimizes
forwarding performance for TCP traffic by forwarding data packets without examining them. Since
the data packets are present in normal TCP traffic only if a corresponding TCP control session is
established, comparing the packets for the control session to the ACLs is sufficient for filtering the
entire session including the data.
However, it is possible to generate TCP data packets without corresponding control packets, in test
or research situations for example. In this case, the default ACL mode does not filter the data
packets, since there is no corresponding control session to filter. To filter this type of TCP traffic,
use the strict ACL TCP mode. This mode compares all TCP packets to the configured ACLs,
regardless of whether the packets are control packets or data packets. If the ACLs permit the
packet, the device creates a session entry for forwarding other TCP packets with the same Layer 3
and Layer 4 addresses.

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NOTE

Regardless of whether the strict mode is enabled or disabled, the device always compares TCP
control packets against the configured ACLs before creating a session entry for forwarding the
traffic.

NOTE

If the device's configuration currently has ACLs associated with interfaces, remove the ACLs from the
interfaces before changing the ACL mode.
To enable the strict ACL TCP mode, enter the following command at the global CONFIG level of the
CLI.
ServerIronADX(config)# ip strict-acl-tcp

Syntax: [no] ip strict-acl-tcp
This command configures the device to compare all TCP packets against the configured ACLs
before forwarding them.
To disable the strict ACL mode and return to the default ACL behavior, enter the following
command.
ServerIronADX(config)# no ip strict-acl-tcp

NOTE
Enter the ip rebind-acl command at the global CONFIG level of the CLI to place the ip strict-acl-tcp or
no ip strict-acl-tcp command into effect.

Enabling strict UDP mode
By default, when you use ACLs to filter UDP traffic, the Brocade device does not compare all UDP
packets against the ACLs. Instead, the device compares the source and destination information
against entries in the session table. The session table contains forwarding entries based on Layer
3 and Layer 4 information:

• If the session table contains a matching entry, the device forwards the packet, assuming that
the first packet the device received that contains the same address information was permitted
by the ACLs.

• If the session table does not contain a matching entry, the device sends the packet to the CPU,
where the software compares the packet against the ACLs. If the ACLs permit the packet
(explicitly by a permit ACL entry or implicitly by the absence of a deny ACL entry), the CPU
creates a session table entry for the packet’s forwarding information and forwards the packet.
For tighter control, the software provides the strict ACL UDP mode. When you enable strict UDP
processing, the device sends every UDP packet to the CPU and compares the packet against the
configured ACLs.

NOTE

If the device's configuration currently has ACLs associated with interfaces, remove the ACLs from the
interfaces before changing the ACL mode.
To enable the strict ACL UDP mode, enter the following command at the global CONFIG level of the
CLI.
ServerIronADX(config)# ip strict-acl-udp

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Enabling strict TCP or UDP mode for flow-based ACLs

Syntax: [no] ip strict-acl-udp
This command configures the device to compare all UDP packets against the configured ACLs
before forwarding them.
To disable the strict ACL mode and return to the default ACL behavior, enter the following
command.
ServerIronADX(config)# no ip strict-acl-udp

NOTE

Enter the ip rebind-acl command at the global CONFIG level of the CLI to place the ip strict-acl-udp
or no ip strict-acl-udp command into effect.

Configuring ACL packet and flow counters
You can configure counters for packets and flows that match entries in an ACL. Using the CLI, you
can display the contents of the counters and clear them:

• The ACL packet counter feature provides an accurate count of packets matching individual ACL
entries.

• The ACL flow counter feature provides an approximate count of flows matching individual ACL
entries. This feature can be used for troubleshooting purposes to provide an indication of flow
activity against an ACL. Each time the Brocade device receives the first packet of a flow
matching an entry in an ACL list, the flow counter for that ACL entry is incremented by one. If a
flow lasts longer than two minutes, the flow counter for the ACL entry is incremented again.

NOTE

The ACL flow counter feature is designed to monitor the general volume of flow activity for an
ACL. It is not intended to be used for accounting purposes.
The ACL flow and packet counters are incremented differently depending on whether packets are
handled by the Management Processor (MP), and whether they are permit or deny flows.
The Management Processor (MP) handles flows as follows.
For flows handled by the Management Processor:

• For permit flows, only flows are counted. If a permit flow lasts longer than two minutes, the flow
counter is incremented again.

• For deny flows, only packets are counted.
By default the ACL packet and flow counters are disabled. To activate them, enter the following
command.
ServerIronADX(config)# enable-acl-counter

Syntax: [no] enable-acl-counter
Once the ACL packet and flow counters are enabled, you can disable them with the no form of the
enable-acl-counter command. Disabling and then re-enabling the ACL packet and flow counters
resets them to zero.
To display the packet and flow counters for ACL 100.

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ServerIronADX# show access-list 100
Extended IP access list 100 (Total flows: 432, Total packets: 42000)
permit tcp 1.1.1.0 0.0.0.255 any (Flows: 80, Packets: 12900)
deny udp 1.1.1.0 0.0.0.255 any (Flows: 121, Packets: 20100)
permit ip 2.2.2.0 0.0.0.255 any (Flows: 231, Packets: 9000)

Syntax: show access-list  |  | all
To clear the flow counters for ACL 100.
ServerIronADX# clear access-list 100

Syntax: clear access-list  |  | all

ACLs and ICMP
This section describes how ACLs can be used to filter traffic based on ICMP packets.

Using flow-based ACLs to filter ICMP packets based on the IP packet
length
To configure an extended ACL that filters based on the IP packet length of ICMP packets, enter
commands such as the following.
ServerIronADX(config)#access-list 105 deny icmp any any echo ip-pkt-len 92
ServerIronADX(config)#access-list 105 deny icmp any any echo ip-pkt-len 100
ServerIronADX(config)#access-list 105 permit ip any any

The commands in this example deny (drop) ICMP echo request packets that contain a total length
of 92 or 100 in the IP header field. You can specify an IP packet length of 1 – 65535. Refer to the
section “ICMP filtering with flow-based ACLs” on page 79 for additional information on using ICMP
to filter packets.

ICMP filtering with flow-based ACLs
Most Brocade software releases that support flow-based ACLs filter traffic based on the following
ICMP message types:

•
•
•
•
•
•
•
•
•
•
•
•

echo
echo-reply
information-request
mask-reply
mask-request
parameter-problem
redirect
source-quench
time-exceeded
timestamp-reply
timestamp-request
unreachable

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• 
Also, to create ACL policies that filter ICMP message types, you can either enter the description of
the message type or enter its type and code IDs. Furthermore ICMP message type filtering is now
available for rule-based ACLs on BigIron Layer 2 Switch and Layer 3 Switch images.

Numbered ACLs
For example, to deny the echo message type in a numbered ACL, enter commands such as the
following when configuring a numbered ACL.
ServerIronADX(config)# access-list 109 deny ICMP any any echo

or
ServerIronADX(config)# access-list 109 deny ICMP any any 8 0

Syntax: [no] access-list 
Syntax: deny | permit icmp  |  | any | host

 |  | any | host

 |  
The deny | permit parameter indicates whether packets that match the policy are dropped or
forwarded.
You can either enter the name of the message type for  or the type number and code
number of the message type. Refer to Table 5 on page 81 for valid values.

Named ACLs
For example, to deny the administratively-prohibited message type in a named ACL, enter
commands such as the following.
ServerIronADX(config)# ip access-list extended melon
ServerIronADX(config-ext-nacl)# deny ICMP any any administratively-prohibited

or
ServerIronADX(config)# ip access-list extended melon
ServerIronADX(config-ext-nacl)# deny ICMP any any 3 13

Syntax: [no] ip access-list extended  | 
Syntax: deny | permit icmp  |  | any | host

 | destination-ip-address/subnet-mask> | any | host

 |  
The extended parameter indicates the ACL entry is an extended ACL.
The  |  parameter allows you to specify an ACL name or number. If using a
name, specify a string of up to 256 alphanumeric characters. You can use blanks in the ACL name
if you enclose the name in quotation marks (for example, “ACL for Net1”). The 
parameter allows you to specify an ACL number if you prefer. If you specify a number, enter a
number from 100 – 199 for extended ACLs.

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The deny | permit parameter indicates whether packets that match the policy are dropped or
forwarded.
You can either use the  and enter the name of the message type or use the
  parameter and enter the type number and code number
of the message. Refer to Table 5 for valid values.

NOTE

“X” in the Type-Number or Code-Number column in Table 5 means the device filters any traffic of that
ICMP message type.

TABLE 5

ICMP message types and codes

ICMP message type

Type

Code

administratively-prohibited

3

13

any-icmp-type

x

x

destination-host-prohibited

3

10

destination-host-unknown

3

7

destination-net-prohibited

3

9

destination-network-unknown

3

6

echo

8

0

echo-reply

0

0

general-parameter-problem

12

1

host-precedence-violation

3

14

host-redirect

5

1

host-tos-redirect

5

3

host-tos-unreachable

3

12

host-unreachable

3

1

information-request

15

0

mask-reply

18

0

mask-request

17

0

net-redirect

5

0

net-tos-redirect

5

2

net-tos-unreachable

3

11

net-unreachable

3

0

packet-too-big

3

4

parameter-problem

12

0

port-unreachable

3

3

precedence-cutoff

3

15

NOTE: This message type indicates that required
option is missing.

log

NOTE: This message includes all parameter problems

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Using ACLs and NAT on the same interface (flow-based ACLs)

TABLE 5

ICMP message types and codes

ICMP message type

Type

Code

protocol-unreachable

3

2

reassembly-timeout

11

1

redirect

5

x

router-advertisement

9

0

router-solicitation

10

0

source-host-isolated

3

8

source-quench

4

0

source-route-failed

3

5

time-exceeded

11

x

timestamp-reply

14

0

timestamp-request

13

0

ttl-exceeded

11

0

unreachable

3

x

NOTE: This includes all redirects.

NOTE: This includes all unreachable messages

Using ACLs and NAT on the same interface (flow-based ACLs)
You can use ACLs and NAT on the same interface, as long as you follow these guidelines:

• You must use the ip strict-acl-tcp command when configuring ACLs and NAT is configured on
the same Layer 2 Switch. (Refer to the instructions below on how to use this command.)

• Do not enable NAT on an interface until you have applied ACLs (as described below) to the
interface. If NAT is already enabled, you must disable it, apply the ACLs, then re-enable NAT on
the interface.

• Enable the strict TCP mode.
• On the inside NAT interface (the one connected to the private addresses), apply inbound ACLs
that permit TCP, UDP, and ICMP traffic to enter the device from the private sub-net.
You can use a standard ACL to permit all traffic (including TCP, UDP, and ICMP traffic) or an
extended ACL with separate entries to explicitly permit TCP, UDP, and ICMP traffic.

NOTE

You do not need to apply ACLs to permit TCP, UDP, and ICMP traffic unless you are applying other
ACLs to the interface as well. If you do not plan to apply any ACLs to a NAT interface, then you do not
need to apply the ACLs to permit TCP, UDP, and ICMP traffic.
Here is an example of how to configure device to use ACLs and NAT on the same interfaces. In this
example, the inside NAT interface is port 1/1 and the outside NAT interface is port 2/2.
The following commands enable the strict TCP mode and configure an ACL to permit all traffic from
the 10.10.200.x sub-net. A second ACL denies traffic from a specific host on the Internet.

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ServerIronADX(config)# ip strict-acl-tcp
ServerIronADX(config)# access-list 1 permit 10.10.200.0 0.0.0.255
ServerIronADX(config)# access-list 2 deny 209.157.2.184

The following commands configure global NAT parameters.
ServerIronADX(config)# ip nat inside source list 1 pool outadds overload
ServerIronADX(config)# ip nat pool outadds 204.168.2.1 204.168.2.254 netmask
255.255.255.0

The following commands configure the inside and outside NAT interfaces. Notice that the ACLs are
applied to the inbound direction on the inside NAT interface, and are applied before NAT is enabled.
In this example, ACL 1 permits all traffic to come into the inside interface from the private sub-net.
ACL 2 denies traffic from a specific host from going out the interface to the private sub-net.
ServerIronADX(config)# interface ethernet 1/1
ServerIronADX(config-if-1/1)# ip address 10.10.200.1 255.255.255.0
ServerIronADX(config-if-1/1)# ip access-group 1 in
ServerIronADX(config-if-1/1)# ip access-group 2 out
ServerIronADX(config-if-1/1)# ip nat inside
ServerIronADX(config-if-1/1)# interface ethernet 2/2
ServerIronADX(config-if-2/2)# ip address 204.168.2.78 255.255.255.0
ServerIronADX(config-if-2/2)# ip nat outside

NOTE
Enter the ip rebind-acl command at the global CONFIG level of the CLI to place the ip strict-acl-tcp
command into effect.

Displaying ACL bindings
You can display which ACLs (IPv4 and IPv6) are bound to which interfaces as shown in the
following.
ServerIronADX# show access-list bindings
Access-list binding configuration:
!
interface ethernet 2
ip access-group 2 in
ipv6 traffic-filter acl1 in
!
interface ve 2
ip access-group 111 in
ipv6 traffic-filter acl2 out

Syntax: show access-list bindings

Troubleshooting rule-based ACLs
Use the following methods to troubleshoot a rule-based ACL:

• To display the number of Layer 4 CAM entries being used by each ACL, enter the show
access-list
 |  | all command. Refer to “Displaying the number of Layer 4 CAM
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• To view the types of packets being received on an interface, enable ACL statistics using the
enable-acl-counter command, reapply the ACLs by entering the ip rebind-acl all command, then
display the statistics by entering the show ip acl-traffic command.

• To determine whether an ACL entry is correctly matching packets, add the log option to the ACL
entry, then reapply the ACL. This forces the device to send packets that match the ACL entry to
the CPU for processing. The log option also generates a Syslog entry for packets that are
permitted or denied by the ACL entry.

• To determine whether the issue is specific to fragmentation, remove the Layer 4 information
(TCP or UDP application ports) from the ACL, then reapply the ACL.
If you are using another feature that requires ACLs, either use the same ACL entries for filtering and
for the other feature, or change to flow-based ACLs.

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IPv6 Access Control Lists

3

IACL overview
ServerIron ADX supports IPv6 Access Control Lists (ACLs) in hardware. The maximum number of
ACL entries you can configure is a system-wide parameter and depends on the device you are
configuring. You can configure up to the maximum number of 1024 entries in any combination in
different ACLs. The total number of entries in all ACLs cannot exceed the system maximum of 1024
By default, IPv6 ACLs are processed in hardware and all IPv6 ACL rules are stored in TCAM.
An IPv6 ACL is composed of one or more conditional statements that pose an action (permit or
deny) if a packet matches a specified source or destination prefix. There can be up to 1024 IPv6
ACL statements per device. When the maximum number of IPv6 ACL rules are reached, the
following error message will display on the console:
IPv6 Hardware ACL rules cannot be configured,exceeds the maximum hardware limit of
1024 entries
Insufficient hardware resource for binding the ACL scale1 to interface Port or
Slot/Port.

In ACLs with multiple statements, you can specify a priority for each statement.The specified
priority determines the order in which the statement appears in the ACL. The last statement in each
IPv6 ACL is an implicit deny statement for all packets that do not match the previous statements in
the ACL.
You can configure an IPv6 ACL on a global basis, then apply it to the incoming IPv6 packets on
specified interfaces. You can apply only one IPv6 ACL to an interface’s incoming traffic. When an
interface receives an IPv6 packet, it applies the statement within the ACL in their order of
appearance to the packet. As soon as a match occurs, the ServerIron ADX takes the specified
action (permit or deny the packet) and stops further comparison for that packet.
Brocade’s IPv6 ACLs enable traffic filtering based on the following information:

•
•
•
•
•

IPv6 protocol
Source IPv6 address
Destination IPv6 address
Source TCP or UDP port (if the IPv6 protocol is TCP or UDP)
Destination TCP or UDP port (if the IPv6 protocol is TCP or UDP)

The IPv6 protocol can be one of the following well-known names or any IPv6 protocol number from
0 – 255:

•
•
•
•
•

Authentication Header (AHP)
Encapsulating Security Payload (ESP)
Internet Control Message Protocol (ICMP)
Internet Protocol Version 6 (IPv6)
Stream Control Transmission Protocol (SCTP)

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• Transmission Control Protocol (TCP)
• User Datagram Protocol (UDP)
NOTE
TCP and UDP filters will be matched only if they are listed as the first option in the extension header.
For TCP and UDP, you also can specify a comparison operator and port name or number. For
example, you can configure a policy to block web access to a specific website by denying all TCP
port 80 (HTTP) packets from a specified source IPv6 address to the website’s IPv6 address.
This chapter contains the following sections:

• “Configuring an IPv6 ACL” on page 87
• “Applying an IPv6 ACL to an interface” on page 93
• “Displaying ACLs” on page 94

Configuration Notes
• Either IPv6 must be enabled globally or an IPV6 address must be configured on an interface
before IPv6 ACLs can be configured.

•
•
•
•

An IPv6 ACL can include up to 1024 entries or statements.
Only named ACLs are supported.
Only Inbound ACLs are supported.
If an IPv6 ACL has the implicit deny condition, make sure it also permits the IPv6 link-local
address, in addition to the global unicast address. Otherwise, routing protocols such as OSPF
will not work. To view the link-local address, use the show ipv6 interface command.

• You cannot disable IPv6 on an interface to which an ACL is bound. Attempting to do so will
cause the system to return the following error message.
ServerIronADX(config-if-e1000-7)#no ipv6 enable
Error: Port 7 has IPv6 ACL configured. Cannot disable IPv6

To disable IPv6, first remove the ACL from the interface.

Processing of IPv6 ACLs
There are two ways that IPv6 ACLs are processed in Brocade devices: in software and in hardware.
This processing differs depending on the software release that you are running. These differences
are described in the following sections.

Prior to release 12.3.01
Prior to release 12.3.01, IPv6 ACLs were processed as described in the following:
For deny and permit actions:
All permit and deny packets are forwarded to the BPs and the BPs perform the ACL processing.

Beginning with release 12.3.01 and later
Beginning with release 12.3.01, IPv6 ACLs are processed as described in the following:

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For deny actions:
All deny packets are dropped in hardware.
For permit actions:
For all traffic, packets are processed in hardware and then forwarded to the BPs. The BPs do
not take any action on the ACLs.
Backwards compatibility option:
You can use the ipv6 flow-based-acl-enable command to provide backwards compatibility for
IPv6 ACL processing. If this command is configured, packets are processed in hardware and
then forwarded to the BPs where the BPs also process the ACLs. This command is configured
as shown in the following.
ServerIronADX(config)# ipv6 flow-based-acl-enable

Syntax: ipv6 flow-based-acl-enable

Configuring an IPv6 ACL
To configure an IPv6 ACL, do the following:
1. Create the IPv6 ACL.
2. Apply the IPv6 ACL to the interface.

Example Configurations
To configure an access list that blocks all Telnet traffic received on port 1/1 from IPv6 host
2000:2382:e0bb::2, enter the following commands.
ServerIronADX(config)# ipv6 access-list fdry
ServerIronADX(config-ipv6-access-list-fdry)# deny tcp host 2000:2382:e0bb:
:2 any eq telnet
ServerIronADX(config-ipv6-access-list-fdry)# permit ipv6 any any
ServerIronADX(config-ipv6-access-list-fdry)# exit
ServerIronADX(config)# int eth 1/1
ServerIronADX(config-if-1/1)# ipv6 traffic-filter fdry in
ServerIronADX(config)# write memory

Here is another example of commands for configuring an ACL and applying it to an interface.
ServerIronADX(config)# ipv6 access-list netw
ServerIronADX(config-ipv6-access-list-netw)#
e0bb::/64 2001:3782::/64
ServerIronADX(config-ipv6-access-list-netw)#
e0ac::2 host 2000:2383:e0aa:0::24
ServerIronADX(config-ipv6-access-list-netw)#
ServerIronADX(config-ipv6-access-list-netw)#

permit icmp 2000:2383:
deny ipv6 host 2000:2383:
deny udp any any
permit ipv6 any any

The first condition permits ICMP traffic from hosts in the 2000:2383:e0bb::x network to hosts in
the 2001:3782::x network.
The second condition denies all IPv6 traffic from host 2000:2383:e0ac::2 to host
2000:2383:e0aa:0::24.
The third condition denies all UDP traffic.

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The fourth condition permits all packets that are not explicitly denied by the other entries. Without
this entry, the ACL would deny all incoming IPv6 traffic on the ports to which you assigned the ACL.
The following commands apply the ACL "netw" to the incoming traffic on port 1/2 and to the
incoming traffic on port 4/3.
ServerIronADX(config)# int eth 1/2
ServerIronADX(config-if-1/2)# ipv6 traffic-filter netw in
ServerIronADX(config-if-1/2)# exit
ServerIronADX(config)# int eth 4/3
ServerIronADX(config-if-4/3)# ipv6 traffic-filter netw in
ServerIronADX(config)# write memory

Here is another example:
ServerIronADX(config)# ipv6 access-list nextone
ServerIronADX(config-ipv6-access-list rtr)# deny tcp 2001:1570:21::/24
2001:1570:22::/24
ServerIronADX(config-ipv6-access-list rtr)# deny udp any range 5 6
2001:1570:22::/24
ServerIronADX(config-ipv6-access-list rtr)# permit ipv6 any any
ServerIronADX(config-ipv6-access-list rtr)# write memory

The first condition in this ACL denies TCP traffic from the 2001:1570:21::x network to the
2001:1570:22::x network.
The next condition denies UDP packets from any source with source UDP port in ranges 5 to 6 and
whose destination is to the 2001:1570:22::/24 network.
The third condition permits all packets containing source and destination addresses that are not
explicitly denied by the first two. Without this entry, the ACL would deny all incoming IPv6 traffic on
the ports to which you assign the ACL.
A show running-config command displays the following:
ServerIronADX(config)# show running-config
ipv6 access-list rtr
deny tcp 2001:1570:21::/24 2001:1570:22::/24
deny udp any range 5 6 2001:1570:22::/24
permit ipv6 any any

A show ipv6 access-list command displays the following:
ServerIronADX(config)# sh ipv6 access-list rtr
ipv6 access-list rtr: 3 entries
deny tcp 2001:1570:21::/24 2001:1570:22::/24
deny udp any range 5 6 2001:1570:22::/24
permit ipv6 any any

The following commands apply the ACL “rtr” to the incoming traffic on ports 2/1 and 2/2.
ServerIronADX(config)# int eth 2/1
ServerIronADX(config-if-2/1)# ipv6 traffic-filter rtr in
ServerIronADX(config-if-2/1)# exit
ServerIronADX(config)# int eth 2/2
ServerIronADX(config-if-2/2)# ipv6 traffic-filter rtr in
ServerIronADX(config)# write memory

Default and Implicit IPv6 ACL Action
The default action when no IPv6 ACLs are configured on an interface is to permit all IPv6 traffic.
However, once you configure an IPv6 ACL and apply it to an interface, the default action for that
interface is to deny all IPv6 traffic that is not explicitly permitted on the interface.

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• If you want to tightly control access, configure ACLs consisting of permit entries for the access
you want to permit. The ACLs implicitly deny all other access.

• If you want to secure access in environments with many users, you might want to configure
ACLs that consist of explicit deny entries, then add an entry to permit all access to the end of
each ACL. The permit entry permits packets that are not denied by the deny entries.
Every IPv6 ACL has the following implicit condition as its last match conditions:
deny ipv6 any any – Denies IPv6 traffic. You must enter a permit ipv6 any any as the last
statement in the access-list if you want to permit IPv6 traffic that were not denied by the
previous statements.

NOTE
If an IPv6 ACL has the implicit deny condition, make sure it also permits the IPv6 link-local address,
in addition to the global unicast address. Otherwise, routing protocols such as OSPF will not work.
To view the link-local address, use the show ipv6 interface command.
The conditions are applied in the order shown above, with deny ipv6 any any as the last condition
applied.
For example, if you want to deny ICMP neighbor discovery acknowledgement, then permit any
remaining IPv6 traffic, enter commands such as the following:
ServerIronADX(config)# ipv6 access-list netw
ServerIronADX(config-ipv6-access-list-netw)# permit icmp 2000:2383:e0bb:
:/64 2001:3782::/64
ServerIronADX(config-ipv6-access-list-netw)# permit ipv6 any any

The first permit statement permits ICMP traffic from hosts in the 2000:2383:e0bb::x network to
hosts in the 2001:3782::x network.
The deny statement denies ICMP neighbor discovery acknowledgement.
The last entry permits all packets that are not explicitly denied by the other entries. Without this
entry, the ACL will deny all incoming IPv6 traffic on the ports to which you assigned the ACL.
Furthermore, if you add the statement deny icmp any any in the access list, then all neighbor
discovery messages will be denied. You must explicitly enter the permit icmp any any nd-na and
permit icmp any any nd-ns statements just before the deny icmp statement if you want the ACLs to
permit neighbor discovery as in the example below.
ServerIronADX(config)# ipv6 access-list netw
ServerIronADX(config-ipv6-access-list-netw)# permit icmp 2000:2383:e0bb:
:/64 2001:3782::/64
ServerIronADX(config-ipv6-access-list-netw)# deny icmp any any
ServerIronADX(config-ipv6-access-list-netw)# permit ipv6 any any

ACL Syntax
NOTES: The following features are not supported:

• ipv6-operator flow-label
• ipv6-operator fragments when any protocol is specified. The option "fragments" can be
specified only when "permit/deny ipv6" is specified. If you specify "tcp" or any other protocol
instead of "ipv6" the keyword, "fragments" cannot be used.

• ipv6-operator routing when any protocol is specified. (Same limitation as for ipv6-operator
fragments)

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IACL overview

• The following ICMPv6 Message Types are not supported:
DECIMAL

<0-255>

ICMP message type

beyond-scope

Destination Unreachable ICMP message, Beyond Scope

destination-unreachable

Destination Unreachable ICMP messages

dscp

Match dscp value in IPv6 packet

echo-reply

Echo Reply ICMP message

echo-request

Echo Request ICMP message

header

Parameter Problem ICMP Message,Header Error

hop-limit

Time Exceeded ICMP Message,In Transit

log

Log matches against this entry

mld-query

MLD Query Message

mld-reduction

MLD Reduction Message

mld-report

MLD Report Message

nd-na

ND Neighbor Advertisement Message

nd-ns

ND Neighbor Solicitation Message

next-header

Parameter Problem ICMP Message,Next Header

no-admin

Destination Unreachable ICMP Message,
Administratively Prohibited

no-route

Destination Unreachable ICMP Message, No Route

packet-too-big

Packet Too Big ICMP Message

parameter-option

Parameter Problem ICMP Message,Option

parameter-problem

Parameter Problem ICMP Messages

port-unreachable

Destination Unreachable ICMP Message, Port Unreachable

reassembly-timeout

Time Exceeded ICMP Message, ReassemblyTimeout

renum-command

Renumber Command ICMP Message

renum-result

Renumber Result ICMP Message

renum-seq-number

Renumber Sequence Number ICMP Message

router-advertisement

Router Advertisement ICMP Message

router-renumbering

All Router Renumbering ICMP Messages

router-solicitation

Router Solicitation ICMP Message

sequence

Sequence number for this entry

time-exceeded

Time Exceeded ICMP Messages

traffic-policy

Attach traffic policy by name

unreachable

Destination Unreachable ICMP message,Address Unreachable

When creating ACLs, use the appropriate syntax below for the protocol you are filtering.
For IPv6 and Supported Protocols Other than ICMP, TCP, or UDP
Syntax: [no] ipv6 access-list 

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Syntax: permit | deny 
 | any | host 
 | any | host 
[ipv6-operator []] [log]
For ICMP
Syntax: [no] ipv6 access-list 
Syntax: permit | deny icmp  | any | host

 | any | host 
[ipv6-operator []]
[ [][] ] | [] [log]
For TCP
Syntax: [no] ipv6 access-list 
Syntax: permit | deny 
 | any | host  [tcp-udp-operator
[source-port-number]]
 | any | host 
[tcp-udp-operator [destination-port- number]]
[ipv6-operator []] [log]
For UDP
Syntax: [no] ipv6 access-list 
Syntax: permit | deny 
 | any | host  [tcp-udp-operator
[source port number]]
 | any | host 
[tcp-udp-operator [destination port number]]
[ipv6-operator []] [log]

TABLE 6

Syntax Descriptions

Arguments...

Description...

ipv6 access-list 

Enables the IPv6 configuration level and defines the name of the IPv6 ACL.
The  can contain up to 199 characters and numbers, but
cannot begin with a number and cannot contain any spaces or quotation
marks.

permit

The ACL will permit (forward) packets that match a policy in the access list.

deny

The ACL will deny (drop) packets that match a policy in the access list.

icmp

Indicates the you are filtering ICMP packets.

protocol

The type of IPv6 packet you are filtering. You can specify a well-known name
for some protocols whose number is less than 255. For other protocols, you
must enter the number. Enter “?” instead of a protocol to list the well-known
names recognized by the CLI. IPv6 protocols include:
AHP – Authentication Header
ESP – Encapsulating Security Payload
IPv6 – Internet Protocol version 6
SCTP – Stream Control Transmission Protocol

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TABLE 6

Syntax Descriptions

Arguments...

Description...

// parameter specify a source prefix
>
and prefix length that a packet must match for the specified action (deny or
permit) to occur. You must specify the  parameter in
hexadecimal using 16-bit values between colons as documented in RFC
2373. You must specify the  parameter as a decimal value. A
slash mark (/) must follow the  parameter and precede the
 parameter.
/

The / parameter specify a
destination prefix and prefix length that a packet must match for the
specified action (deny or permit) to occur. You must specify the
 parameter in hexadecimal using 16-bit values
between colons as documented in RFC 2373. You must specify the
 parameter as a decimal value. A slash mark (/) must follow
the  parameter and precede the  parameter

any

When specified instead of the / or
/ parameters, matches any IPv6
prefix and is equivalent to the IPv6 prefix::/0.

host

Allows you specify a host IPv6 address. When you use this parameter, you
do not need to specify the prefix length. A prefix length of all128 is implied.

icmp-message

ICMP packets are filtered by ICMP messages. See the "Configuring IPv6
ICMP Features" section of the "Configuring IPv6 Connectivity" chapter of the
ServerIron ADX TrafficWorks Switching and Routing Guide.

tcp

Indicates the you are filtering TCP packets.

udp

Indicates the you are filtering UDP packets.

// parameter specify a source prefix
>
and prefix length that a packet must match for the specified action (deny or
permit) to occur. You must specify the  parameter in
hexadecimal using 16-bit values between colons as documented in RFC
2373. You must specify the  parameter as a decimal value. A
slash mark (/) must follow the  parameter and precede the
 parameter.
/

92

The / parameter specify a
destination prefix and prefix length that a packet must match for the
specified action (deny or permit) to occur. You must specify the
 parameter in hexadecimal using 16-bit values
between colons as documented in RFC 2373. You must specify the
 parameter as a decimal value. A slash mark (/) must follow
the  parameter and precede the  parameter

any

When specified instead of the / or
/ parameters, matches any IPv6
prefix and is equivalent to the IPv6 prefix::/0.

host

Allows you specify a host IPv6 address. When you use this parameter, you
do not need to specify the prefix length. A prefix length of all128 is implied.

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TABLE 6

3

Syntax Descriptions

Arguments...

Description...

tcp-udp-operator

The  parameter can be one of the following:
eq – The policy applies to the TCP or UDP port name or number you enter
after eq.
gt – The policy applies to TCP or UDP port numbers greater than the port
number or the numeric equivalent of the port name you enter after gt. Enter
"?" to list the port names.
lt – The policy applies to TCP or UDP port numbers that are less than the
port number or the numeric equivalent of the port name you enter after lt.
neq – The policy applies to all TCP or UDP port numbers except the port
number or port name you enter after neq.
range – The policy applies to all TCP port numbers that are between the first
TCP or UDP port name or number and the second one you enter following
the range parameter. The range includes the port names or numbers you
enter. For example, to apply the policy to all ports between and including 23
(Telnet) and 53 (DNS), enter the following: range 23 53. The first port
number in the range must be lower than the last number in the range.
The  and  for the
tcp-udp-operator is the number of the port.

ipv6-operator

Allows you to filter the packets further by using one of the following options:
dscp – The policy applies to packets that match the traffic class value
in the traffic class field of the IPv6 packet header. This operator allows
you to filter traffic based on TOS or IP precedence. You can specify a
value from 0 – 63.
• fragments – The policy applies to fragmented packets that contain a
non-zero fragment offset.

•

NOTE: This option is not applicable to filtering based on source or
destination port, TCP flags, and ICMP flags.
• routing – The policy applies only to IPv6 source-routed packets.
NOTE: This option is not applicable to filtering based on source or
destination port, TCP flags, and ICMP flags.
log

Allows statistics that match the ACL statement to be entered in the Syslog.

Applying an IPv6 ACL to an interface
To apply an IPv6 ACL to an interface, enter commands such as the following:
ServerIronADX(config)# interface ethernet 3/1
ServerIronADX(config-if-e100-3/1)# ipv6 traffic-filter access1 in

This example applies the IPv6 ACL “access1” to incoming IPv6 packets on Ethernet interface 3/1.
As a result, Ethernet interface 3/1 denies all incoming packets from the site-local prefix
fec0:0:0:2::/64 and the global prefix 2001:100:1::/48 and permits all other incoming packets.
Syntax: ipv6 traffic-filter  in
For the  parameter, specify the name of an IPv6 ACL created using the ipv6
access-list command.
The in keyword applies the specified IPv6 ACL to incoming IPv6 packets on the interface.

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Using an ACL to Restrict SSH Access

Displaying ACLs
To display the ACLs configured on a device, enter the show ipv6 access-list command. Here is an
example:
ServerIronADX# show ipv6 access-list
ipv6 access-list v6-acl1: 1 entries
deny ipv6 any any
ipv6 access-list v6-acl2: 1 entries
permit ipv6 any any
ipv6 access-list v6-acl3: 2 entries
deny ipv6 2001:aa:10::/64 any
permit ipv6 any any
ipv6 access-list v6-acl4: 2 entries
deny ipv6 2002:aa::/64 any
permit ipv6 any any
ipv6 access-list v6-acl5: 6 entries
permit tcp 2002:bb::/64 any
permit ipv6 2002:bb::/64 any
permit ipv6 2001:aa:101::/64 any
permit ipv6 2001:aa:10::/64 2001:aa:102::/64
permit ipv6 host 2001:aa:10::102 host 2001:aa:101::102
permit ipv6 any any fragments

Syntax: show ipv6 access-list []

Displaying ACLs bound to an interface
To display ACLs bound to an interface, enter the show access-list bindings command. Here is an
example:
ServerIronADX# show access-list bindings
Access-list binding configuration:
!
interface ethernet 1
ipv6 traffic-filter ipv61 in
!
interface ethernet 2
ipv6 traffic-filter icmp_any in
!
ServerIronADX 1000#

Syntax: show access-list bindings

Using an ACL to Restrict SSH Access
To configure an ACL that restricts SSH access to an IPv6 device, first create the
named ACL with the ACL statements. Then use the ssh access-group command to
restrich SSH access for IPv6:

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ServerIronADX(config)# ipv6 access-list test2
ServerIronADX(config-ipv6-access-list test2)# deny ipv6 host 2000:1::1 any log
ServerIronADX(config-ipv6-access-list test2)# permit ipv6 2000:1::0/32 any
ServerIronADX(config-ipv6-access-list test2)# permit ipv6 2000:2::0/32 any
ServerIronADX(config-ipv6-access-list test2)# permit ipv6 host 2000:3::1 any
ServerIronADX(config-ipv6-access-list test2)# exit
ServerIronADX(config)# ssh access-group ipv6 test2

Syntax: [no] ssh access-group ipv6 

Using an ACL to Restrict Telnet Access
To configure an ACL that restricts Telnet access to an IPv6 device, first create the named ACL with
the ACL statements. Then use the telnet access-group command to restrict Telnet access for IPv6:
ServerIronADX(config)# ipv6 access-list test1
ServerIronADX(config-ipv6-access-list test1)# deny ipv6 host 2000:1::1 any log
ServerIronADX(config-ipv6-access-list test1)# permit ipv6 2000:1::0/32 any
ServerIronADX(config-ipv6-access-list test1)# permit ipv6 2000:2::0/32 any
ServerIronADX(config-ipv6-access-list test1)# permit ipv6 host 2000:3::1 any
ServerIronADX(config-ipv6-access-list test1)# exit
ServerIronADX(config)# telnet access-group ipv6 test1

Syntax: telnet access-group ipv6 

Logging IPv6 ACLs
Logging for IPv6 ACLs is disabled by default. To enable logging, enable it for each IPv6 ACL, then
include the logging option in an ACL statement. Logging at both levels need to be configured in
order for statistics for packets that match the condition to be logged. For example:
ServerIronADX(config)# ipv6 access-list acl2
ServerIronADX(config-ipv6-access-list-acl2)# logging-enable
ServerIronADX(config-ipv6-access-list-acl2)# permit tcp host
2002:200:12d:1300:204:23ff:fec7:dabf any eq http
ServerIronADX(config-ipv6-access-list-acl2)# deny icmp 2002:200:12d:1300::/64 any
echo-reply log
ServerIronADX(config-ipv6-access-list-acl2)# permit ipv6 any any

Syntax: [no] logging-enable

NOTE

Syntax for the log option in an IPv6 ACL statement are presented in the section “ACL Syntax” on
page 89.

NOTE
Permit logging is not currently supported.

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Network Address Translation

Introduction
Network Address Translation (NAT) translates one IP address into another. For example, it
translates an internal private IP address (nonregistered) into an external unique IP address
(registered) used on the Internet.

FIGURE 5

Mapping an internal address to an external address

Internal

External
Internet or
Intranet Backbone

SI

150.1.1.1

10.1.1.1

NAT also provides a more graceful renumbering strategy for organizations changing service
providers or voluntarily renumbering into Classless Interdomain Routing (CIDR) blocks.
The standard NAT support described in this section provides translation for hosts attached to
private networks on the ServerIron ADX, and is separate from the virtual IP address features
provided for Server Load Balancing (SLB). For example, standard NAT is not related to source IP
addresses used for multinetting the ServerIron ADX, performing health checks on remote servers,
and so on.

Configuring NAT
The following types of NAT are supported:

• Static NAT — Maps a specific global IP address (Internet IP address) with a specific private
address. Static translation ensures the software always maps the same public address to a
given private address. For example, you can map 10.1.1.1 to 150.1.1.1. Use static NAT when
you want a specific host in the private network to always use the same Internet address when
communicating outside the private network. ServerIron ADX supports both inside to outside
network translation and outside to inside network Nat translation.

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• Dynamic NAT — Maps private addresses to Internet addresses. The Internet addresses come
from a pool of addresses that you configure. For example, you can dynamically translate the
global pool 150.1.1.10 - 19 to private pool 10.1.1.1 - 254. In Figure 6, the pool is the range of
addresses from 209.157.1.2/24 – 209.157.1.254/24. With dynamic NAT, the software uses a
round robin technique to select a global IP address to map to a private address from a pool you
configure.
Dynamic NAT uses Port Address Translation (PAT). Otherwise, the return traffic cannot be
reliably de-multiplexed to the correct internal client.

NOTE
You can configure both dynamic and static NAT on the same device. When you configure both types
of NAT, static NAT takes precedence over dynamic NAT. Thus, if you configure a static NAT translation
for a private address, the ServerIron ADX always uses that translation instead of creating a dynamic
one.

Configuring static NAT
Use the ip nat inside source static command to explicitly map a private address to an Internet
address. Static NAT ensures a specific host in the private network is always mapped to the Internet
address you specify.
To map a private address 10.10.10.69 to an Internet address 209.157.1.69, enter the command
such as the following.
ServerIronADX(config)# ip nat inside source static 10.10.10.69 209.157.1.69

Syntax: [no] ip nat inside source static   [] list []
The  variable specifies the private IP address.
The  variable specifies the IP address. The ServerIron ADX supports up to 255 global IP
addresses.
The  variable specifies a value of 1 or 2 and enables static NAT redundancy. A value of 2
means higher priority, and will be the owner of the NAT IP as long as the system is up.
The list parameter specifies the access list identified by the  variable that will permit only
the configured tcp or udp port numbers.

Configuring dynamic NAT
To configure dynamic NAT, perform the following tasks:

• Configure a standard or extended ACL for each private address range for which you want to
provide NAT.

NOTE

Named ACLS are not supported with NAT. You must use a numbered ACL.

• Configure a pool for each consecutive range of Internet addresses to which you want NAT to be
able to map the private addresses specified in the ACLs. Each pool must contain a range with
no gaps. If your Internet address space has gaps, configure separate pools for each
consecutive range within the address space.

• Associate a range of private addresses (specified in a standard or extended ACL) with a pool.

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Configuring an address pool
Use the ip nat pool command to configure the address pool. For an example, refer to “Dynamic NAT
configuration example 1” on page 100.
Syntax: [no] ip nat pool    netmask  | prefix-length
 | port-pool-range 
The  parameter specifies the name assigned to the pool. It can be up to 255
characters long and can contain special characters and internal blanks. If you use internal blanks,
you must use quotation marks around the entire name.
The  parameter specifies the IP address at the beginning of the pool range. Specify the
lowest-numbered IP address in the range.
The  parameter specifies the IP address at the end of the pool range. Specify the
highest-numbered IP address in the range.

NOTE

The address range cannot contain any gaps. Make sure you own all the IP addresses in the range.
If the range contains gaps, you must create separate pools containing only the addresses you own.
The netmask  | prefix-length  parameter specifies a classical sub-net mask
(example: netmask 255.255.255.0) or the length of a CIDR prefix (example: prefix-length 24). The
ServerIron ADX supports up to 255 global IP addresses.
The port-pool-range  parameter enables dynamic NAT redundancy, where the
 can be 1 or 2. A range value of 2 indicates higher priority for the NAT IP. A 2 value
also means the source ports allocated for the NAT IP are from the higher range.

Associating a range of private addresses with a pool and enabling PAT
Use ip nat inside source list to associate a private address range with a pool of Internet addresses
and enable PAT. For an example, refer to “Dynamic NAT configuration example 1” on page 100.
Syntax: [no] ip nat inside source list  pool 
The inside source keyword specifies that the translation applies to private addresses sending
traffic to the Internet (inside source).
The list  parameter specifies a standard or extended ACL. Named ACLS are not supported
with NAT. You must use a numbered ACL.
The pool  parameter specifies the pool name. You must create the pool before you
can use it with this command.

NAT configuration examples
The following sections provide both Dynamic and Static NAT configuration examples.

NOTE
A ServerIron ADX can have a maximum of 255 global IP addresses, in a single pool or multiple pools.

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Dynamic NAT configuration example 1
This section describes the Dynamic NAT configuration shown in Figure 6.

FIGURE 6

Minimum required commands

Internet

ip address 10.10.1.2 255.255.255.0
ip default-gateway 10.10.1.1
ip nat inside
ip nat inside source list 10 pool out_pool
ip nat pool out_pool 209.157.1.2 209.157.1.30 prefix-len
!
interface ethernet 2
port-name To-gateway-router
!
interface ethernet 1
port-name Inside-Network
!
access-list 10 permit 10.10.1.0 0.0.0.255
!

Remote Server
63.253.63.50

Gateway
VE: 10.10.1/24 (Primary)
209.157.1.1/24 (Secondary)

ServerIron ADX
10.10.1.2
NAT pool IP:
209.157.1.2–209.157.1.30

SI ADX

PC
PC
10.10.1.100 10.10.1.101

Server
10.10.1.102

Server
10.10.1.103

Figure 6 shows an example of a network using dynamic NAT on a ServerIron ADX ADX. The device is
acting as a gateway to connect a private network to the Internet. The private network, which can
also be considered as the inside network, is using IP addresses in the range of 10.10.1.2 10.10.1.254 with a 24-bit subnet mask.
The ServerIron ADX is connected to the Internet through a router. The outside interface of the
ServerIron ADX has a global IP address of 209.157.1.1. The ServerIron ADX also has a pool of
global IP addresses, which are used to map internal IP addresses.
Minimum required commands for dynamic NAT configuration.
1. Identify an internal and external interface on the ServerIron ADX. In this example, Ethernet 1/2
and 1/1 are used.
int eth 1/2
int eth 1/1

2. Assign IP addresses to the interfaces and define the outside and inside boundaries of the NAT
mechanism.
ServerIronADX(config)# int eth 1/2
ServerIronADX(config-if-1/2)# ip address 209.157.1.1/24
ServerIronADX(config-if-1/2)# ip nat outside
ServerIronADX(config-if-1/2)# int eth 1/1
ServerIronADX(config-if-1/1)# ip address 10.10.10.1/24
ServerIronADX(config-if-1/1)# ip nat inside

On Switch (S) code, enable NAT globally.
ServerIronADX(config)# ip nat inside

On Router (R) code, enable NAT on interfaces (both ip nat inside and outside should be
enabled). The interfaces can also be physical interfaces (not necessarily virtual interfaces).

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ServerIronADX(config-ve-2)#ip nat inside
ServerIronADX(config-ve-3)#ip nat outside

3. Configure a numbered ACL and permit the IP addresses on the inside. Then define the global
address pool and enable dynamic NAT.
ServerIronADX(config)# access-list 101 permit ip 10.10.1.0/24 any
ServerIronADX(config)# ip nat pool global_pool 209.157.1.2 209.157.1.254
prefix-length 24

Make sure you specify permit in the ACL, rather than deny. If you specify deny, the ServerIron
ADX will not provide NAT for the addresses.
4. Tie the inside source list to the global pool and enable PAT (overload) to send traffic out the
external interface.
ServerIronADX(config)# ip nat inside source list 101 pool global_pool

5. rconsole into the BP and verify the translation is working correctly.
rconsole x/x
show ip nat statistic
show ip nat translation

Dynamic NAT configuration example 2
In the following example, the ServerIron ADX is configured to translate inside hosts in the 20.20.0.0
network to unique global addresses in the 15.15.15.15/24 network.

FIGURE 7

Example of a dynamic NAT configuration - translating inside host addresses to unique pool
addresses

Internet

Remote Server

Global IP address pool: 15.15.15.15 to 15.15.15.25

1/1

Outside Interface

SI
1/5

Inside Interface
Inside IP addresses: 20.20.0.0

This example requires that Interfaces 1/5 and 1/1 be configured as Inside and Outside interfaces
respectively as shown.
ServerIronADX(config)# interface ethernet 1/5
ServerIronADX(config-if-e1000-1/5) ip address 20.20.50.1 255.255.0.0
ServerIronADX(config-if-e1000-1/5) ip nat inside

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ServerIronADX(config)# interface ethernet 1/1
ServerIronADX(config-if-e1000-1/5) ip address 30.30.0.1 255.255.0.0
ServerIronADX(config-if-e1000-1/5) ip nat outside

The following command creates a pool of IP NAT addresses from 15.15.15.15 to 15.15.15.25
named p1.
ServerIronADX(config)# ip nat pool p1 15.15.15.15 15.15.15.25 prefix-len 24

An ACL is created to permit traffic from inside hosts in the 20.20.0.0 network as shown.
ServerIronADX(config)# access-list 1 permit 20.20.0.0 0.0.255.255

The following command ties the inside source list defined in ACL “1” to the pool named “p1” and
enables PAT to send traffic out the interface defined as “outside”.
ServerIronADX(config)# ip nat inside source list 1 pool p1

Static NAT configuration example
The following examples describe how to configure a Static NAT configuration for Inside to Outside
and Outside to Inside translation for the example shown in Figure 8.

FIGURE 8

Example of a static NAT configuration using router code

Internet

Remote Server

Global IP address: 15.15.15.15

Outside Interface

1/1

SI
1/5

Inside Interface
Local IP address: 20.20.5.6

Configured for inside to outside translation
In the following example, the ServerIron ADX is configured to translate the local host IP address
20.20.5.6 to the unique global address 15.15.15.15.
This example requires that Interfaces 1/5 and 1/1 be configured as Inside and Outside interfaces
respectively as shown.
ServerIronADX(config)# interface ethernet 1/5
ServerIronADX(config-if-e1000-1/5) ip address 20.20.50.1 255.255.0.0
ServerIronADX(config-if-e1000-1/5) ip nat inside

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ServerIronADX(config)# interface ethernet 1/1
ServerIronADX(config-if-e1000-1/5) ip address 30.30.0.1 255.255.0.0
ServerIronADX(config-if-e1000-1/5) ip nat outside

The following command configures the ServerIron ADX to translate IP packets with a local IP
address of 20.20.5.6 to the global IP address 15.15.15.15.
ServerIronADX(config)# ip nat inside source static 20.20.5.6 15.15.15.15

Configured for outside to inside translation
To configure the network shown in Figure 8 for Outside to Inside translation the only requirement is
that the Interface configured as an Outside interface must be configured with an additional IP
address in the 15.15.15.0/24 network as shown in the following.
ServerIronADX(config)# interface ethernet 1/1
ServerIronADX(config-if-e1000-1/5) ip address 30.30.0.1 255.255.0.0
ServerIronADX(config-if-e1000-1/5) ip address 15.15.15.100 255.255.0.0
ServerIronADX(config-if-e1000-1/5) ip nat outside

PAT
Dynamic NAT uses Port Address Translation (PAT). Since there is no one-to-one mapping between
private addresses and global addresses, PAT maps a client's IP address and TCP/UDP port to both
a global IP address and a TCP/UDP port. In this way, the ServerIron ADX can map many private
addresses to the same public address and use TCP/UDP ports to uniquely identify the private
hosts.
PAT maps a client’s IP address and TCP or UDP port number to both an IP address and a TCP or
UDP port number. In this way, the ServerIron ADX can map many private addresses to the same
public address and use TCP or UDP port numbers to uniquely identify the private hosts.

NOTE

PAT is also called overloading an inside global address.
Example
Inside address

Outside address

10.10.10.2:6000

209.157.1.2:1024

10.10.10.3:6000

209.157.1.2:1025

10.10.10.4:6000

209.157.1.2:1026

NAT is mapping the same global IP address to three different private addresses along with their
TCP or UDP ports, but uses a different TCP or UDP port number for each private address to
distinguish them. Notice that the PAT feature does not attempt to use the same TCP or UDP port
number as in the client’s packet.

Forwarding packets without NAT translation
When ServerIron ADX receives a non-SYN packet for a TCP flow from an internal NAT client and no
sessions are found, then by default ServerIron drops that packet. Optionally, you can forward that
packets without NAT translation by entering the following command.

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Translation timeouts

ServerIronADX(config)# nat-forward-no-session

Syntax: [no] nat-forward-no-session

Translation timeouts
The NAT translation table contains all the currently active NAT translation entries on the device. An
active entry is one the ServerIron ADX creates for a private address when the client at that address
sends traffic.
NAT performs the following steps to provide an address translation for a source IP address:

• NAT looks in the translation table for an active NAT entry for the translation. If the table
contains an active entry for the session, the ServerIron ADX uses that entry.

• If NAT does not find an active entry in the NAT translation table, NAT creates an entry and
places the entry in the table. The entry remains in the table until the entry times out.
Each NAT entry remains in the translation table until the entry ages out.
After the configuration of a NAT timeout the following occurs:

• Existing entries of the modified protocol remain in the translation table.
• If existing session entries send or receive packets then the timeout value is updated to the new
configured value.

• If existing session entries do not process any traffic they will continue to age out in accordance
with the old timeout value.

• When the timeout (age of the session) expires, forward and reverse sessions in the ServerIron
ADX are deleted with no further actions. If traffic is received on this flow the ServerIron ADX
drops the packets because it will not find sessions related to that particular flow.

Configuring the NAT translation aging timer
Use the ip nat translation command to alter the NAT translation aging timer.
The NAT translation table contains all the currently active NAT translation entries on the device. An
active entry is one that the ServerIron ADX created for a private address when that client at that
address sent traffic to the Internet. NAT performs the following steps to provide an address
translation for a source IP address:

• The feature looks in the NAT translation table for an active NAT entry for the translation. If the
table contains an active entry for the session, the ServerIron ADX uses that entry.

• If NAT does not find an active entry in the NAT translation table, NAT creates an entry and
places the entry in the table. The entry remains in the table until the entry times out.
ServerIronADX(config)# ip nat translation tcp-timeout 1800

Syntax: [no] ip nat translation dns-timeout | finrst-timeout | icmp-timeout | syn-timeout |
tcp-timeout | udp-timeout  maximum
Syntax: [no] ip nat translation max-entries 
The dns-timeout keyword indicates connections to a Domain Name Server (DNS). The default is
120 seconds.

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The finrst-timeout keyword identifies TCP FIN (finish) and RST (reset) packets, which normally
terminate TCP connections. The default is 120 seconds. This timer is not related to tcp-timeout,
which applies to packets to or from a host address that is mapped to an global IP address and a
TCP port number (PAT feature). The finrst-timeout applies to packets that terminate a TCP session,
regardless of the host address or whether PAT is used.
The icmp-timeout keyword indicates timeout for NAT ICMP flows
The syn-timeout keyword indicates timeout for NAT TCP flows after a SYN
The tcp-timeout keyword indicates dynamic entries that use PAT based on TCP port numbers. The
default is 120 seconds. This timer applies only to TCP sessions that do not end “gracefully”, with a
TCP FIN or TCP RST.
The udp-timeout keyword indicates dynamic entries that use PAT based on UDP port numbers. The
default is 120 seconds.
The  parameter specifies number of seconds, 0– 3600. Use maximum to set the maximum
timeout value. For example, 3,600 seconds.
The max-entries  parameter specifies the maximum number of NAT entries

Stateless static IP NAT
A ServerIron ADX creates sessions for Static NAT by default. You can prevent a ServerIron ADX from
creating sessions for static NAT traffic with the following command.
ServerIronADX(config)# [no] ip nat stateless

Syntax: ip nat stateless
For “ip nat stateless“ to work, the existing command, “ip nat inside source static” must already be
configured.
Example
ip nat inside source static 10.45.16.103 10.45.16.10

NOTE
FTP, RTSP and other similar complex protocols are not supported. The traffic applicable for IP NAT
Stateless are TCP, UDP, and ICMP.

NOTE

You must reload a ServerIron ADX whenever changes are made to a running IP NAT configuration.

Redundancy
The IP NAT Redundancy feature implements a separate protocol to negotiate IP address ownership
of NAT IP addresses.

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Redundancy

The new protocol is similar to the symmetric VIP protocol and uses any L2 link to exchange the NAT
PDUs. Both ServerIronADXs will run a “symmetric VIP like” protocol to report and receive ownership
(similar to the VLAN AD protocol in symmetric SLB). When one ServerIron ADX goes down, the peer
ServerIron ADX will become the master for that NAT IP (in case of static NAT) or NAT pool (in case of
dynamic NAT). However, the NAT IP/NAT pool ownership is used only to decide which ServerIronADX
responds to the ARP request for the NAT IP. Both ServerIronADXs are allowed to use the NAT IP in
keeping with the design for symmetric VIP (sym-active SLB).
The global ip policy dependency is as follows:

• SLB — not needed
• IP NAT — not needed
• TCS — An ip policy must be defined. Without it, caching will not work.

Enabling IP NAT
When a ServerIron ADX is configured with Switch code, NAT is enabled globally but when it is
configured with Router Code, it is enabled per-interface.

NOTE

ServerIron ADX ADX does not support IP NAT inside and outside on the same physical interface.

Enabling IP NAT globally
The following command enables IP NAT globally.
ServerIronADX(config)# ip nat inside

Syntax: [no] ip nat inside

Enabling IP NAT per-interface
When enabled per-interface, IP NAT must be enabled exclusively “inside” or “outside” on a physical
or virtual interface as shown in the following example.
ServerIronADX(config)# interface ethernet 1/5
ServerIronADX(config-if-e1000-1/5) ip nat inside

Syntax: [no] ip nat [inside | outside]
The inside parameter configures the interface as an IP NAT inside interface.
The outside parameter configures the interface as an IP NAT outside interface.

Enabling static NAT redundancy
To enable static NAT redundancy, enter the ip nat inside source static command such as the
following.
ServerIronADX(config)# ip nat inside source static 10.10.10.10 63.32.23.1 2

Syntax: ip nat inside source static   
The existing ip nat inside command has been extended to include a , which is used
to determine the owner of the NAT IP address.

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The  can be 1 or 2. 2 is the higher priority, and will be the owner of the NAT IP as
long as the system is up.

Enabling dynamic NAT redundancy
To enable dynamic NAT redundancy, enter commands such as the following.
ServerIronADX(config)# ip nat pool foo 63.23.1.2 63.23.1.4 prefix 24
ServerIronADX(config)# ip nat pool foo port-pool-range 2

Syntax: ip nat pool  port-pool-range 
The port-pool-range  parameter supports redundancy for IP NAT pool addresses.
This parameter is similar to the priority value for static NAT, except it also determines the range of
source ports allocated by the NAT IP (which prevents source port collision).
In ServerIron ADX, the ip nat pool  port-pool-range command is mandatory for running
router code in HA setups. This command decides the ownership of the IP NAT pool and, when using
router code, this command has to be used in tandem with ip nat pool  
 command.
The  can be 1 or 2. A range value of 2 indicates higher priority for the NAT IP. It also
means the source ports allocated for the NAT IP are from the higher range.

NOTE
A distribution of port ranges is not required for static NAT, as it does not involve PAT.

Displaying NAT information
The following sections describe how to display NAT information.

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Displaying NAT statistics
To display NAT statistics, enter commands such as the following.
ServerIronADX# rconsole 1 1
ServerIronADX1/1#ServerIronADX_Lower1/1# show ip nat stat
Debug counters:
TCP FWD:
send nat unreachable tcp fwd) =0 nat tcp no ports avl = 2867811
nat tcp status zero = 0 nat tcp ip status zero = 0
nat tcp usr index null = 0
TCP REV:
send nat unreachable (tcp rev) =0 nat tcp rev no ports avl = 0
nat tcp rev status zero = 0 nat tcp rev ip status zero = 0
nat tcp rev usr index null = 0
UDP FWD:
send nat unreachable (udp_fwd) =0 nat udp fwd no ports avl = 0
nat udp fwd status zero = 0 nat udp fwd ip status zero = 0
nat udp fwd usr index null = 0
UDP REV:
send nat unreachable (udp rev) =0 nat udp rev no ports avl = 0
nat udp rev status zero = 0 nat udp rev ip status zero = 0
nat udp rev usr index null = 0
nat corruption = 0 rtsp port unavailable = 0
RTSP inside alloc same = 53271 RTSP reply port not same= 0
Wrong port range = 0
Total translations: 12433 (0 static, 12433 dynamic)
Hits: 5786108 Misses: 94
Expired translations: 5773769
Dynamic mappings:
pool p1: prefix_len= 24
start 15.15.15.15 end 15.15.15.20
total addresses 6 overloaded
[0]: h: 0 t: 0 m: 248a6000 T: 384 f: 384
[1]: h: 0 t: 0 m: 248ab000 T: 384 f: 384
[2]: h: 0 t: 0 m: 29f33000 T: 384 f: 384
[3]: h: 0 t: 0 m: 2a5cb000 T: 384 f: 384
[4]: h: 0 t: 0 m: 2a5d4000 T: 384 f: 384
[5]: h: 0 t: 0 m: 2a5dd000 T: 384 f: 384
[0]: h: 0 t: 0 m: 248a8000 T: 320 f: 320
[1]: h: 0 t: 0 m: 29f30000 T: 320 f: 320
[2]: h: 0 t: 0 m: 2a5c4000 T: 320 f: 320
[3]: h: 0 t: 0 m: 2a5cd000 T: 320 f: 320
[4]: h: 0 t: 0 m: 2a5d6000 T: 320 f: 320
[5]: h: 0 t: 0 m: 2a5df000 T: 320 f: 320
[0]: h: 972 t: 5653 m: 248a2000 T: 7168 f: 4681
[1]: h: 972 t: 5653 m: 2a5bc000 T: 7168 f: 4681
[2]: h: 2520 t: 656 m: 2a5c0000 T: 7168 f: 5304
[3]: h: 2520 t: 655 m: 2a5c7000 T: 7168 f: 5303
Sess: Total 2000000, Avail 1950226, NAT 24886
Stream media=1, RTSP=(1:94547), MMS=(1:0), PNM=(1:0)
Inside global
Last Inside Local xmit pkts xmit bytes
15.15.15.15
20.20.2.15
89909
7619664
15.15.15.16
20.20.2.16
89907
7619447
15.15.15.17
20.20.2.11
67428
5714424
15.15.15.18
20.20.2.12
67428
5714424
15.15.15.19
20.20.2.13
67432
5714763
15.15.15.20
20.20.2.14
67434
5714883

108

rx pkts
44954
44950
33712
33712
33714
33714

rx bytes
8023584
8023575
6017592
6017592
6017949
6017949

cnt
2487
2487
1864
1865
1865
1865

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Syntax: show ip nat statistics

TABLE 7

Display fields for show ip nat statistics

This field...

Displays...

send nat unreachable (tcp fwd)

Indicates the number of times that a “port unreachable” message was
generated for NAT TCP forward traffic.

nat tcp no ports avl

Indicates the number of times that a “port unreachable” message was
generated because the ServerIron could not get a port from the port pool for
a NAT IP for TCP forward traffic.

nat tcp status zero

Indicates the number of times that an error in NAT translation for TCP forward
traffic.

nat tcp ip status zero

Indicates errors in NAT translation for TCP forward traffic.

nat tcp usr index null

Indicates the number of times that a “port unreachable” message was
generated because the ServerIron could not create a user session for TCP
forward traffic.

send nat unreachable (tcp rev)

Indicates the number of times that a “port unreachable” message was
generated for TCP reverse traffic.

nat tcp rev no ports avl

Indicates the number of times that a “port unreachable” message was
generated because the ServerIron could not get a port from the port pool for
an IP NAT for TCP reverse traffic.

nat tcp rev status zero

Indicates the number of times that an error in NAT translation for TCP reverse
traffic has occurred.

nat tcp rev ip status zero

Indicates the number of times that an error in NAT translation for TCP reverse
traffic has occurred.

nat tcp rev usr index null

Indicates the number of times that a “port unreachable” message was
generated because the ServerIron could not create a user session for TCP
reverse traffic.

send nat unreachable (udp fwd)

Indicates the number of times that a “port unreachable” message was
generated for UDP forward traffic.

nat udp fwd no ports avl

Indicates the number of times that a “port unreachable” message was
generated because the ServerIron could not get a port from the port pool for
a NAT IP for UD forward traffic.

nat udp fwd status zero

Indicates the number of times that an error in NAT translation for UDP
forward traffic has occurred.

nat udp fwd status zero

Indicates the number of times that an error in NAT translation for UDP
forward traffic has occurred.

nat udp fwd usr index null

Indicates the number of times that a “port unreachable” message was
generated because the ServerIron could not create a user session for UDP
forward traffic.

send nat unreachable (udp rev)

Indicates the number of times that a “port unreachable” message was
generated for UDP reverse traffic because the Serveriron could not get a port
from the port pool for a NAT IP.

nat udp rev no port avl

Indicates the number of times that a “port unreachable” message was
generated because the ServerIron could not get a port from the port pool for
a NAT IP for UDP reverse traffic.

nat udp rev status zero

Indicates the number of times that an error in NAT translation for UDP reverse
traffic has occurred.

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TABLE 7

Display fields for show ip nat statistics (Continued)

This field...

Displays...

nat udp rev ip status zero

Indicates the number of times that an error in NAT translation for UDP reverse
traffic has occurred.

nat udp rev usr index null

Indicates the number of times that a “port unreachable” message was
generated because the ServerIron could not create a a user session for UDP
reverse traffic.

sw l4 nat corruption

Indicates the number of instances of NAT session corruption.

rstp port unavailable

Indicates the number of times that a NAT port was not available for RSTP.

RTSP inside alloc same

Indicates the number of times that the used port and proposed client port
were the same for RSTP.

RTSP reply port not same

Indicates the number of times that the used port and proposed client port
were not the same for RTSP.

Wrong port range

Indicates the number of times that the NAT port used a port in the wrong port
range. For example, where a NAT port used a port from the normal port pool
range for RTSP.

Port Pool Parameters
[x]

The variable represented by "x" represents the index of the IP address in the
IP NAT pool. For example, [0] refers to the first IP address in the IP pool
(216:220:209:230). [1] refers to the second IP address in this IP pool
(216:220:209:231).

h

The value following "h:" refers to the head of the port pool for the IP address
in the IP NAT pool. The head indicates the location in the port pool where the
next port will be allocated from.

t

The value following "t:" refers to the tail of the port pool for the IP address in
the IP NAT pool. The tail indicates the location in the port pool where the next
port will be freed from.

T

The value following "T:" refers to the total number of ports in the port pool for
that IP address in the IP NAT pool.

f

The value following "f:" refers to the number of free ports in the port pool for
this IP address.

Displaying NAT translation
To display the currently active NAT translations, enter the following command.
ServerIronADX(1/1)# show ip nat translation
Pro Inside global
tcp 10.1.1.92:11021

Inside local
5.1.1.2:32784

Outside local
10.1.1.1:23

Outside global
10.1.1.1:23

Syntax: show ip nat translation

NOTE

You can enter this command only when you rconsole in to a BP. The command is not supported on
the Main Processor CPU.

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4

Display fields for show ip nat translation

This field...

Displays...

Pro

When PAT is enabled, this field indicates the protocol NAT is using to uniquely
identify the host. NAT can map the same IP address to multiple hosts and use
the protocol port to distinguish among the hosts. This field can have one of the
following values:
• tcp – In addition to this IP address, NAT is associating a TCP port with the
host on the private network.
• udp – In addition to this IP address, NAT is associating a UDP port with the
host on the private network.

Inside global

The Internet address mapped to the private address listed in the Inside local
field for inside NAT.

Inside local

The private address mapped to the Internet private address listed in the Inside
global field for inside NAT.

Outside global

The destination of the traffic. If PAT is enabled, the TCP or UDP port also is
shown.
NOTE: Outside NAT is not supported.

Outside local

The destination of the traffic. If PAT is enabled, the TCP or UDP port also is
shown.
NOTE: Outside NAT is not supported.

Displaying NAT redundancy information
You can display information about the state of the static NAT IP or NAT pool (dynamic), the MAC
address used, and the configured priority. The MAC address used for the NAT IP is a special
construct, where the last 3 bytes of the MAC address are derived from the shared NAT IP address
(similar to the symmetric MAC).
To display NAT redundancy information, enter the following command.
ServerIronADX# show ip nat redundancy (on active)
NAT Pool Start IP: 10.1.1.150 Mac address: 020c.db01.0196
State: Active Priority: High
NAT Pool Start IP: 10.1.1.91
Mac address: 020c.db01.015b
State: Active Priority: High
NAT Pool Start IP: 10.1.1.92
Mac address: 020c.db01.015c
State: Active Priority: High
NAT Pool Start IP: 10.1.1.95
Mac address: 020c.db01.015f
State: Active Priority: High

The two “Priority” options are “High” and “Low”. That is, 2 or 1.
The two “State” options are “Active” and “standby”.

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Clearing NAT entries from the table

ServerIronADX# show ip nat redundancy (on standby)
NAT Pool Start IP: 10.1.1.150 Mac address: 020c.db01.0196
State: Standby Priority: Low
Standby Idle count: 0 Threshold: 20
NAT Pool Start IP: 10.1.1.91
Mac address: 020c.db01.015b
State: Standby Priority: Low
Standby Idle count: 0 Threshold: 20
NAT Pool Start IP: 10.1.1.92
Mac address: 020c.db01.015c
State: Standby Priority: Low
Standby Idle count: 0 Threshold: 20
NAT Pool Start IP: 10.1.1.95
Mac address: 020c.db01.015f
State: Standby Priority: Low
Standby Idle count: 0 Threshold: 20

Syntax: show ip nat redundancy

Displaying VRRPE information
To display VRRPE information, enter the following command.
ServerIronADX_Lower# show ip vrrp-e brief
Total number of VRRP-Extended routers defined: 2
Interface VRID CurPri P State Master addr
Backup addr
v5
v10

1
2

125 P Master Local
125 P Master Local

Syntax: show ip vrrp-e brief

Unknown
Unknown

VIP
5.1.1.9
10.1.1.9

Clearing NAT entries from the table
Use the clear ip nat command to manually clear entries from the NAT table.
Syntax: clear ip nat  inside    
The  parameter specifies the protocol type and can be tcp or udp plus its global or local
port number.
To clear a specific NAT entry based on the private and global IP addresses, enter the command
such as the following.
ServerIronADX# clear ip nat inside 209.157.1.43 10.10.10.5

This command clears the inside NAT entry that maps private address 10.10.10.5 to Internet
address 209.157.1.43.
Syntax: clear ip nat inside  
To clear all static and dynamic entries from the NAT translation table, enter the following command.
ServerIronADX# clear ip nat all

Syntax: clear ip nat all

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Syn-Proxy and DoS Protection

5

This chapter describes how to configure Syn-Proxy and DOS protection features on the ServerIron
ADX Traffic Managers.

Understanding Syn-Proxy
Syn-Proxy™ allows TCP connections to be terminated on the ServerIron ADX. When Syn-Proxy is
enabled, the ServerIron ADX completes the three-way handshake with a connecting client. Only
when the three-way handshake is completed does the ServerIron ADX establish a connection with
the destination server and forward packets from the client to the server.
In a TCP SYN attack, the attacker floods a host with TCP SYN packets. The host replies with
SYN-ACK packets, but the attacker does not send the ACK packet. The handshake remains
incomplete, and the host goes into a perpetual wait-state for it to be completed. As a result, the
resources available for TCP connections are rapidly depleted and the host is unable to accept any
further TCP connections.
ServerIron ADX prevents these types of attacks by sitting in between the host and attacker. When
an attacker sends the SYN packet, ServerIron ADX receives it and replies to it with SYN-ACK. If the
attacker doesn’t send an ACK to the ServerIron ADX, the handshake isn’t completed with the
ServerIron ADX. In this situation, the server never receives any packets from the attacking client
and is oblivious to the attack.
If the SYN is from a valid client and not an attacker, ServerIron ADX completes the handshake and
forwards the SYN to the host. ServerIron ADX creates a session at this time; only when the
three-way handshake is complete.

NOTE

In software syn-proxy, throughput for syn-attack is 1.18Mbps per core.

Syn-Proxy auto control
Syn-Proxy can be explicitly enabled or disabled through a CLI command or setup to be
automatically enabled when the TCP SYN packet arrival rate exceeds a configured threshold or
disabled when the TCP SYN packet arrival rate falls below a configured threshold.

Difference between ServerIron ADX and JetCore Syn-Proxy Behavior
ServerIron ADX and JetCore-based ServerIron devices show different behavior with TCP Syn-Proxy.
A ServerIron ADX drops TCP SYN ACKs entering an interface where tcp syn-proxy is configured
unless it can match those SYN ACKs to an existing session. The JetCore-based ServerIron devices
forward them through. The behaviour of the ServerIron ADX provides enhanced protection against
SYN attacks relative to the protection available from JetCore-based ServerIron devices.

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Configuring Syn-Proxy

If you want your ServerIron ADX to behave more like a JetCore-based ServerIron device, you can use
any of the following three workarounds:
1. Enable syn-proxy on the server interface
2. Enable ip nat
3. Enable "server security-on-vip-only".

Configuring Syn-Proxy
This section contains the following sections:

•
•
•
•
•

“Enabling SYN-Proxy” on page 114
“Setting Attack-Rate-Threshold” on page 115
“Setting SYN-Ack-Window-Size” on page 115
“Setting Reset-Using-Client-MAC” on page 115
“Retransmitting TCP SYNs” on page 116

NOTE

Syn-Proxy is not supported for IPv6 for releases earlier than 12.2.0.

NOTE

In a syn-proxy configuration for a local client, if an ARP entry for the client is not stored, the first TCP
connection may need to retransmit none-syn packets since it may get dropped until the ServerIron
ADX stores an ARP entry for the client. There will only be a performance impact for the very first
connection.

NOTE
If you use log action inside access-list deny rules, then you cannot combine such an ACL with
hardware-based syn-proxy on the same interface. To do so, you can either remove log action or
disable hardware syn-proxy using the server disable-hw-syn-cookie command. Remember that if you
disable hardware syn-proxy, you will harm syn-proxy performance.

NOTE
DSR is not supported with SYN-proxy and is supported with SYN-def.

Enabling SYN-Proxy
To activate Syn-Proxy, follow these steps:
1. Globally enable Syn-Proxy, using the following command:
ServerIronADX(config)# ip tcp syn-proxy

Syntax: ip tcp syn-proxy

NOTE

The ip tcp syn-proxy command must be executed at the global configuration level. If it is
executed at the interface configuration level it will not take effect.
2. Configure a port and enter the interface configuration mode, using the following commands:

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ServerIronADX(config)# interface ethernet 2/1
ServerIronADX(config-if-e1000-2/1)# ip tcp syn-proxy in

Syntax: interface ethernet 
Syntax: ip tcp syn-proxy in
The ip tcp syn-proxy command can be configured for either a physical interface (as shown) or a
ve interface.

Setting Attack-Rate-Threshold
A DoS attack threshold specifies the number of SYNs, without corresponding ACKs, the ServerIron
ADX accepts before writing a warning message to the system log (every 60 seconds for the duration
of the attack).
To configure a threshold value for the SYN attack rate, use the following command:
ServerIronADX(config)# server syn-cookie-attack-rate-threshold 2000

Syntax: server syn-cookie-attack-rate-threshold 
 is a number between 1 and 10,000,000. The default is 1000.

NOTE

If you do not configure a threshold, the ServerIron ADX does not write SYN attack messages to the
log file.
If the number of SYNs (without corresponding ACKs), received on the ServerIron ADX exceeds the
specified threshold of 2000, the ServerIron ADX writes the following message to the log file every
60 seconds for the duration of the attack:
"CRITICAL:

syn-cookie attack rate 2005 exceeds attack rate threshold 2000"

Setting SYN-Ack-Window-Size
To globally set the TCP window size that the ServerIron ADX uses on a SYN-ACK packet sent back to
a client with SYN-Cookie, use the following command:
ServerIronADX(config)# server syn-proxy-syn-ack-window-size 5000

Syntax: [no] server syn-proxy-syn-ack-window-size 
 is the window size. The range from 1 to 65536. The default is 8192.
This command works with a syn-proxy configuration. By having syn-ack-window-size configured, the
window size of the SYN-ACK packet sent from ServerIron ADX to client will have the configured
.
This feature can be used to prevent the client from sending HTTP-Gets before the server side 3-way
handshake is established.

Setting Reset-Using-Client-MAC
NOTE
In this rare corner-case, the reset-using-client-mac command is needed to send a reset to the client.
To globally send a Reset to the client using the client MAC address on the interfaces where
Syn-Proxy is enabled, use the following command:

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ServerIronADX(config)#ip tcp syn-proxy reset-using-client-mac

Syntax: [no] ip tcp syn-proxy reset-using-client-mac
This command is useful only when the client cannot be reached using the ServerIron ADX default
gateway and the default gateway of the server is different than the default gateway of the
ServerIron ADX.

Retransmitting TCP SYNs
When Syn-Proxy is enabled, the ServerIron ADX completes the TCP three-way handshake with a
connecting client prior to forwarding packets between the client and the destination server. This
action allows the ServerIron ADX to forward to the server only packets associated with an
established connection.
After completing the three-way handshake with the client, the ServerIron ADX sends a SYN to the
destination server to attempt to establish a connection with the server. If the ServerIron ADX did
not receive an ACK from the destination server within 8 seconds, the ServerIron ADX sent a TCP
RESET to the client.
The ServerIron ADX performs retransmissions in 3-second intervals. If the ServerIron ADX does not
receive an ACK from the destination server, it retransmits the SYN. After sending a SYN to the
destination server, if the ServerIron ADX does not receive an ACK from the server after three
seconds, the ServerIron ADX retransmits the SYN to the server. If the SYN is still unacknowledged
after three more seconds, the ServerIron ADX retransmits the SYN to the server again. If after three
retransmission attempts, the destination server still has not responded with an ACK, the ServerIron
ADX sends a TCP RESET to the client to abort the connection.
Retransmitting the SYN to the server in this way allows the server to respond in case the initial
SYNs sent by the ServerIron ADX are lost, without having to reset the connection with the client. The
ServerIron ADX can retransmit SYNs for up to 65,536 pending connections concurrently.
This functionality is enabled by default when you enable syn-proxy. No CLI configuration is
necessary. The output of show tcp-attack displays information about SYN retransmissions.

Setting the time range for a valid ACK packet
This feature sets a timer factor that determines the time range to accept a valid ACK packet. This
feature is configured with the following command.
ServerIronADX(config)# ip tcp syn-proxy ack-validate-multiplier 3

Syntax: [no] ip tcp syn-proxy ack-validate-multiplier 
The  variable provides the contents of the timer factor in the following equation used
to determine the time range used:
(timer factor +1) * 8 seconds
Example where the timer factor is set to 3.
The valid window is 3 + 1) * 8 = 32 seconds
Since we check the ACK packet using HASH data from two windows, the MAX time is 64 seconds.
Where the timer factor is set to 3, this HASH value will change every 32 seconds.
As a result, the valid ACK range = (timer factor +1) * 8 seconds * 2

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Limiting syn-proxy feature to defined VIPs
With this feature enabled, the syn packets are dropped if a virtual server IP port is not defined
under a VIP configuration. This feature is enabled with the following command.
ServerIronADX(config)# server syn-cookie-check-vport

Syntax: [no] server syn-cookie-check-vport

Setting the source MAC address
With this feature enabled, the SYN-ACK reply packets will have their source MAC address set to the
MAC address of the ServerIron ADX. This can be helpful to avoid flooding in the case of a SYN to
unknown uncast or broadcast address. This feature is enabled with the following command.
ServerIronADX(config)# server syn-cookie-set-sa

Syntax: [no] server syn-cookie-set-sa

Limiting the syn-proxy feature to VIP traffic only
This feature directs the ServerIron ADX to apply the Syn-Proxy feature to VIP traffic only (not to
pass-through traffic). This feature is enabled with the following command.
ServerIronADX(config)# server security-on-vip-only

Syntax: [no] server security-on-vip-only

Dropping ACK packets with no data
This feature applies where Syn-Proxy is enabled. Configuring this feature causes ACK packets with
no data to be dropped after the ServerIron ADX responds witha SYN-ACK to the client SYN. An ACK
packet with data is forwarded to the BP and processed by the BP.
This feature is enabled with the following command.
ServerIronADX(config)# server virtual-name-or-ip www.altergo.com 207.95.55.1
ServerIronADX(config-vs-www.alterego.com)# port http drop-ack-with-no-data

Syntax: [no] port  drop-ack-with-no-data
This feature is helpful in the event of a real SYN attack with a valid ACK packet sent but with no
data packets afterwards

Setting a minimum MSS value for SYN-ACK packets
The default condition of the ServerIron ADX is to generate SYN-ACK packets with a Maximum
Segment Size (MSS) that is equal or nearly equal to the client’s MSS value. This process disregards
the MSS value of the server. This can result in dropped packets or other unexpected behavior in
situations where the MSS value of the server is smaller than the MSS value of the client.
This feature allows you to set the MSS value for SYN-ACK packets generated by the ServerIron ADX
regardless of the client’s MSS value. A minimum MSS value can be enabled in any of the following
configurations:

• Global level – configures the TCP MSS value at the global level

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• Virtual server lever – configures the TCP MSS value for all virtual ports under a specified virtual
server

• Virtual port level – configures the TCP MSS value for a specified virtual port
• Destination IP – configures the TCP MSS value for pass-through traffic to a specified
destination IP address

NOTE

tcp-mss will work when syn-proxy is enabled. If syn-proxy is turned off, tcp-mss will not take effect.
If the configured mininum MSS is larger than the client's actual MSS value, the ServerIron ADX will
use the client's MSS value in SYN-ACK.

Hierarchy of operation
When multiple levels of the minimum MSS value are configured, the MSS value used by the
ServerIron ADX is determined by the following hierarchy.
1. Virtual Port Level – Values configured at this level take precedence over any other MSS setting
on the ServerIron ADX.
2. Virtual Server level – Only values configured at the Virtual Port level take precedence over MSS
values configured at this level.
3. Global level – Values configured at this level take effect over all SYN-ACK packets generated by
a ServerIron ADX unless the MSS value is configured at one of the levels previous described in
1, 2 or 3.

Setting the MSS value at the global level
To globally set the MSS value for all SYN-ACK packets generated by a ServerIron ADX, use the
following command:
ServerIronADX(config)# tcp-mss 128

Syntax: [no] tcp-mss 
The  variable specifies MSS value for all SYN-ACK packets generated by the ServerIron
ADX regardless of the client’s MSS value. This value can be from 64 to 9216. Make sure that the IP
MTU of the interfaces is always greater than the MSS value.

NOTE

When tcp-mss is configured at the global level, the same value will work for both IPv4 traffic and IPv6
traffic.

Setting the MSS value at the virtual server level
To set the MSS value for all of the ports under a virtual server on a ServerIron ADX, use the
following command:
ServerIronADX(config)# server virtual-name-or-ip v1
ServerIronADX(config-vs-v1)# tcp-mss 128

Syntax: [no] tcp-mss 

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The  variable specifies MSS value for all SYN-ACK packets generated by the ServerIron
ADX for this virtual server regardless of the client’s MSS value. This value can be from 64 to 9216.
Make sure that the IP MTU of the interfaces is always greater than the MSS value.

Setting the MSS value at the virtual port level
To set the MSS value for a specific virtual port on a ServerIron ADX, use the following command:
ServerIronADX(config)# server virtual-name-or-ip v1
ServerIronADX(config-vs-v1)# port http tcp-mss 128

Syntax: [no] port  tcp-mss 
The  variable specifies MSS value for all SYN-ACK packets generated by the ServerIron
ADX for the port specified by the  variable regardless of the client’s MSS value. This
value can be from 64 to 9216. Make sure that the IP MTU of the interfaces is always greater than
the MSS value.

Setting the MSS value for pass-through traffic to a specified destination IP
address
To set the MSS value for ServerIron ADX pass-through traffic to a specified destination IP address,
use the following commands.
ServerIronADX(config)# tcp-mss 128 destination-ip 207.95.55.1

For IPv4
Syntax: [no] tcp-mss  destination-ip 
For IPv6
Syntax: [no] tcp-mss  destination-ipv6 
The  variable specifies MSS value for all SYN-ACK packets that are ServerIron ADX
pass-through traffic to a destination IP address specified by the  variable. This value
can be from 64 to 9216. Make sure that the IP MTU of the interfaces is always greater than the
MSS value.
The  or  cannot be a Virtual server IP address.

Negotiated MSS value set
Once tcp-mss is configured with the minimum value, the ServerIron ADX will generate a negotiated
MSS value in SYN-ACK base on the configured minimum MSS value. This MSS value will be the
final MSS value after negotiation.
For example, if a user configures tcp-mss 1200, which is in the range of 1024 and 1440, a
ServerIron ADX will use the lower 1024 as the negotiated MSS value in the SYN-ACK.

TABLE 9

MSS values for IPv4, IPv6 and IPv4 jumbo
MSS value

IPv4

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TABLE 9

MSS values for IPv4, IPv6 and IPv4 jumbo
MSS value

IPv6

64, 236, 516, 946, 1004, 1420, 1432, 1440

IPv4 Jumbo

256, 536, 966, 1024, 1452, 1460, 4038, 8960

Configuring Syn-Proxy auto control
Syn-proxy auto control operates the same as the normal Syn-proxy feature except that it is enabled
and disabled based-on the arrival rate of TCP SYN packets on the ServerIron ADX. This is described
in “Syn-Proxy auto control” on page 113. The following steps describe how to configure your
ServerIron ADX for Syn-proxy auto control.
1. Set the SYN-Proxy auto control threshold levels – This procedure described in “Setting the
SYN-Proxy auto control thresholds” on page 120, sets the thresholds for enabling and
disabling Syn-Proxy during operation of the ServerIron ADX.
2. Set the interval time for counting TCP SYN packets – This procedure described in “Setting the
interval time for counting TCP SYN packets” on page 121, sets the time period over which the
thresholds set in Step 1 are evaluated.
3. Define Syn-Proxy on an in-bound interface – This is described in Step 2 of the procedure for
“Enabling SYN-Proxy” on page 114.

Considerations for configuring Syn-proxy auto control
The following details concerning operation of the Syn-proxy feature should be considered when
configuring the Syn-proxy auto control feature on a ServerIron ADX:

• All traffic including SLB and pass-through traffic is brought to a BP. Consequently, regardless of
whether or not an interface has the syn-proxy feature enabled, if the threshold set for the rate
of syns received per-second is exceeded for all ports on a ServerIron ADX, Syn-proxy auto
control is enabled and will stay enabled as long as the rate remains above the configured
off-threshold value.

• For interfaces that do not have the syn-proxy feature enabled, there will not be any syn attack
protection even when Syn-proxy is enabled through auto control. Consequently, for the
Syn-proxy auto control feature to work as expected, we recommend that syn-proxy be enabled
on all interfaces.

Setting the SYN-Proxy auto control thresholds
To activate Syn-Proxy auto control, follow these steps:
Globally enable Syn-Proxy auto control by setting the thresholds for enabling and disabling
Syn-Proxy as shown in the following command.
ServerIronADX(config)# ip tcp syn-proxy on-threshold 1000 off-threshold 500

Syntax: ip tcp syn-proxy on-threshold  off-threshold 
The on-threshold parameter is used to define the rate of syns received per-second (specified by the
 variable) at which the Syn-Proxy feature is enabled on the ServerIron ADX.

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The on-threshold-value variable is used with the on-threshold parameter and specifies the
number of TCP SYN packets received per-second. When this value is exceeded for an interval
time defined by the server syn-attack-detection-interval command, Syn Proxy is enabled on the
ServerIron ADX. This value should be set to a much higher value than the normal TCP SYN
packet arrival rate.
The off-threshold parameter is used to define the rate of syns per-second (specified by the
 variable) at which the Syn-proxy feature is disabled (after being previously
enabled) on the ServerIron ADX.
The off-threshold-value variable is used with the off-threshold parameter and specifies the
number of TCP SYN packets received per-second. When the rate received drops below this
value, the ServerIron ADX waits ten seconds and then disables Syn-proxy. The
variable must be less than the  variable.

Setting the interval time for counting TCP SYN packets
The rate at which Syn-proxy is enabled and disabled is determined by the thresholds set in the ip
tcp syn-proxy on-threshold  off-threshold  command
over the time period specified in the server syn-attack-detection-interval command. This interval is
configured on the ServerIron ADX as shown in the following.
ServerIronADX(config)# server syn-attack-detection-interval 10

Syntax: server syn-attack-detection-interval 
The  variable defines the interval that is used to define the time for
counting TCP SYN packets. The range of settings for this interval is 1 to 10 with each level
representing 100 ms. Consequently, the interval can be from 100 ms to 1 second. If the interval
value is smaller, the reaction time for enabling Syn-proxy is shorter, and the measurement of the
TCP syn-packet arrival rate is less accurate. If the interval value is larger, the reaction time for
enabling syn-proxy is longer, and the measurement of TCP syn-packet arrival rate is more accurate.
The default interval value is 3 (in effect 300ms).

Displaying Syn-Proxy Commands
This section contains the following sections:

• “Displaying TCP Attack Information” on page 122
• “Displaying Server Traffic information” on page 122
• “Displaying SYN Cookie Information” on page 123

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Displaying TCP Attack Information
The show server tcp-attack command displays attack information for connection rates counters.
ServerIronADX# show server tcp-attack
Connection counters:
Current conn rate =
0
Attack counters:
Current attack rate =
Client-side counters:
SYN rcvd =
Valid ACKs rcvd =
Client pkt rcvd =
ACK without data dropp =
Destination-side counters:
SYN sent =
Duplicate SYN sent =
Server pkt rcvd =

Max conn rate =

0

1

Max attack rate =

6
3
15

0

SYN-ACK sent =
Invalid ACKs rcvd =
Data pkt stored =

6
33
3

0
3
0
21

SYN-ACK rcvd =
Duplicate SYN-ACK rcvd =
Stored pkt sent =

3
0
0

Syntax: show server tcp-attack [debug | fast-path]

Displaying Server Traffic information
The show server traffic command displays four counters that help to analyze incoming traffic and
determine the DOS attack occurrence. Be sure to issue show L4-traffic from the SSM CPU (not the
MP).
ServerIronADX# show server traffic
Client->Server
= 3760614467
Drops
=
0
Fw_drops
=
0
FIN_or_RST
= 169210866
Disable_drop
=
0
Stale_drop
=
9
SYN def/proxy RST
=
0
Out of Memory
=
0
last conn rate
=
0
last TCP attack rate =
0
fast vport found
=
0
Fwd to non-static FI =
0

122

TCP forward FIN
Fast path FWD FIN
Fast path SLB SYN
Duplicate SYN
TCP ttl FIN recvd
Sessions in DEL_Q
Fwd sess not found
Sess rmvd from delQ
New sess sync sent
TCP SYN received
TCP SYN to MP
TCP SYN ACK received
TCP pkt received
TCP pkt to MP

=
=
=
=
=
=
=
=
=
=
=
=
=
=

0
0
0
0
0
0
0
0
0
0
0
0
0
0

Dropped VIP pings

=

0

Server->Client
Aged
Rev_drops
old-conn
Exceed_drop
Unsuccessful
Server Resets
Out of Memory
max conn rate
max TCP attack rate
fast vport n found
Dup stale SYN

= 2169558899
=
17568293
=
0
=
0
=
0
=
0
=
0
=
0
=
16283
=
0
=
477
=
0

TCP reverse FIN
Fast path REV FIN
Dup SYN after FIN
Duplicate sessions
TCP ttl reset recvd
Sess force deleted
sess already in delQ

=
=
=
=
=
=
=

0
0
0
0
0
0
0

New
TCP
TCP
TCP
TCP

=
=
=
=
=

0
0
0
0
0

sess sync recvd
SYN dropped
SYN ACK to MP
SYN ACK dropped
pkt dropped

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Syntax: show server traffic

TABLE 10

Field Descriptions for show L4-traffic

Field

Description

last conn rate

Rate of TCP traffic per second. This includes all TCP traffic, including TCP SYN DoS
attacks

max conn rate

Peak rate of TCP traffic (per second) encountered on this device.

last TCP attack rate

Rate of TCP Dos attacks per second. This rate is delayed by 1 to 2 minutes.

max TCP attack rate

Peak rate of TCP DoS attacks (per second) encountered on this device. This rate is
delayed by 1 to 2 minutes.

Displaying SYN Cookie Information
This show server syn-cookie command displays information about the SYN AKS that are sent and
received.
ServerIronADX#show server syn-cookie
CPU SYNs processed :
4
CPU SYN-ACKs sent :
4
CPU Valid ACKs rcvd :
92951930
Invalid ACKs rcvd :
1741885
ACL passed :
0
Frags allowed :
0
ACK without data dro :
0
Invalid vport :
0

AXP SYNs processed :
AXP SYN-ACK sent :
AXP Valid ACKS rcvd :

92853225
92853225
253002850

ACL failed :
Frags dropped :

0
73009

Syntax: show server syn-cookie

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TABLE 11

Output Descriptions for show server syn-cookie

Field

Description

CPU SYNs rcvd
AXP SYNs rcvd

Number of SYNs received on ServerIron ADX ports that have the Syn-Proxy feature
enabled.

CPU SYN-ACKs sent
AXP SYN-ACKs sent

Number of SYN ACKs sent from the ServerIron ADX to the client

CPU Valid ACKs rcvd
AXP Valid ACKs rcvd

Number of valid ACKs received from the client.

Invalid ACKs rcvd

Number or invalid ACKs received from the client.

ACL passed

Number of ACL lookups that the ServerIron ADX passed.

ACL failed

Number of ACL lookups that the ServerIron ADX denied.

Frags allowed

Number of fragmented packets allowed.

Frags dropped

Number of fragmented packets dropped.

ACK without datp dro:
Invalid vport

DDoS protection
A Distributed Denial of Service (DDoS) attack is employed to cause a denial of service to legitimate
users by consuming all or most of the CPU and memory resources on a ServerIron ADX or on real
servers. The ServerIron ADX provides protection and prevents well-known DDoS attacks such as
Xmas-tree attack, syn fragment, address sweep and others. The ServerIron ADX prevents these
attacks by defining filters for each type of attack coupled with a drop or log action. These filters are
then bound to an interface. All packets that match the filter on the bound interface are dropped or
logged as defined in the configuration. Filters can be defined according to a generic rule as shown
in “Configuring a Generic Rule” on page 125 or applied from built-in rules as described in Table 13,
Table 15, Table 16 and Table 17. Filters are applied to IPv4 and IPv6 traffic where appropriate.
The following sections describe how to configure a security filter, define rules within a security filter
and bind a security filter to an interface.

•
•
•
•
•
•
•
•

124

“Configuring a security filter” on page 125
“Configuring a Generic Rule” on page 125
“Configuring a rule for common attack types” on page 127
“Configuring a rule for ip-option attack types” on page 129
“Configuring a rule for icmp-type options” on page 130
“Configuring a rule for IPv6 ICMP types” on page 131
“Configuring a rule for IPv6 ext header types” on page 132
“Binding the filter to an interface” on page 133

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Configuring a security filter
Configuring a a security filter requires you to define it by name and configure rules within it as
shown in the following.
ServerIronADX(config)# security filter filter1
ServerIronADX(config-sec-filter1)#rule xmas-tree drop

Syntax: security filter 
The  variable specifies the filter being defined that will then be bound to a port.
The rule command defines the attack method that is being filtered for. For each rule, you can
configure whatever action needs to be taken if an attack occurs. The ServerIron ADX can log the
attack and drop the attacking packet. Rules that can be used are described in Tables 12 thorugh
17 of this chapter.
Some rules are hardware-based and are programmed in the CAM. For these rules, the default
action is to drop the packet. These rules cannot be logged, and no message can be logged when an
attack occurs. But there are counters that you can check to determine if an attack has occurred.
Example
ServerIronADX(config)# security filter filter1
ServerIronADX(config-sec-filter1)# rule xmas-tree log
ServerIronADX(config-sec-filter1)# rule address-sweep 1 3 drop log

NOTE

There is no set limit on the number of filters that can be configured on a ServerIron ADX but a
maximum of 10 rules can be bound to a single interface. The global limit depends upon the available
memory.

Configuring a Generic Rule
Apart from regular rules, such as those configured above, there is also a generic rule. A generic rule
needs to be defined before it can be bound to a filter. In the following example, a rule (gen1) is
configured to match a tcp packet with source-ip greater than 10.10.1.101, a tcp dest-port greater
than 20 and a string "400" at the 3rd byte offset from l4-data.
ServerIronADX(config)# security generic gen1
ServerIronADX(config-sec-gen-gen1)# ip-source gteq ip 10.10.1.101
ServerIronADX(config-sec-gen-gen1)# tcp-dest gt val 20
ServerIronADX(config-sec-gen-gen1)# l4-data 3 eq str "400"

Syntax: {no} security generic 
The  variable specifies the generic rule defined that will then be bound to a
filter.
The following conditions can be applied to any of the fields in the mac-header, ip-header, l4-header
(TCP/UDP), and l4-data offset to create generic rules:
eq

equals

gt

greater-than

gteq

greater-than-or-equals

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lt

less-than

lteq

less-than-or-equals

neq

not-equals

The configured generic rule will have to be bound to a filter, to take effect.
ServerIronADX(config)# security filter filter1
ServerIronADX(config-sec-filter1)# rule generic gen1 drop

Syntax: {no} rule generic  [log | no-log] [drop | no-drop]
The  variable is the name of the preciously defined generic rule that
you want to bind to a filter:
The log parameter directs the ServerIron ADX to log traffic on the bound interface that matches the
generic rule specified by the configured . The no-log parameter disables
this function.
The drop parameter directs the ServerIron ADX to drop traffic on the bound interface that matches
the generic rule specified by the configured . The no-drop parameter
disables this function.
Table 13 describes some attack types that require a generic rule.

TABLE 12

126

Common attack types that require a generic rule

Attack Type

Description

Information tunneling

Attacker attempts to pass information in and out of the network incognito.
Packets appear to be performing one function. In reality, they are performing
another function. For example, a remote user may be engaged in a root shell
session on a protected host, but all transmissions appear to be ICMP echo
requests and replies.
Use security generic to handle this attack type.

Well Known Attacks

There are many documented attacks that can be identified by using a
pattern, also known as a signature.
Use security generic for this attack type. It provides you the flexibility of
locating attacks having a pattern.

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Configuring a rule for common attack types
As described in “Configuring a Generic Rule” on page 125, you can create a custom rule to manage
DDoS attacks. In addition, ServerIron ADX has built-in rules to manage common attack types. In
this case, the rule command is used with a  variable specified in Table 13.
The following example configures a the "filter1" security filter with a rule to drop packets that are
associated with a "xmas tree" attack.
ServerIronADX(config)# security filter filter1
ServerIronADX(config-sec-filter1)#rule xmas-tree drop

Syntax: [no] rule  [log | no-log] [drop | no-drop]
The  variable is specified as one of the options described in Table 13.
The log parameter directs the ServerIron ADX to log traffic on the bound interface that matches the
rule specified by the configured . The no-log parameter disables this function.
The drop parameter directs the ServerIron ADX to drop traffic on the bound interface that matches
the rule specified by the configured . The no-drop parameter disables this function.

TABLE 13

Rules for common attack types and descriptions

Attack Type

Description

syn-fragments

A SYN-fragment attack floods the target host with SYN-packet fragments.
The host stores the fragments, in order to reassemble them. By not
completing the connection, and flooding the server or host with such
fragmented SYN packets, the host’s memory buffer would eventually fill up.
A SYN packet need not be fragmented. It is very small. Use syn-fragments to
drop any SYN packet with the more-fragments bit on.

syn-and-fin-set

Attacker sends a packet with both SYN and FIN bits set to see what kind of
system reply is returned, and then use the system information for further
attacks using known system vulnerabilities.
Use syn-and-fin-set to drop packets having both the SYN and FIN bits set in
the flags field

tcp-no-flags

TCP packets are normally sent with at least one bit set in the flags field.
Use tcp-no-flags to drop TCP packet with a missing or malformed flags field.

icmp-fragments

ICMP fragments can be used to exploit the vulnerabilities in the packet
reassembly code. Enabling icmp-fragments allows you to create a rule that
can be configured to drop or log fragmented ICMP packets.

deny-all-fragments

IP fragments can be used to exploit the vulnerabilities in the packet
reassembly code of specific IP stack implementations. When you enable
deny-all-fragments, the ServerIron ADX drops all IP fragments.

land-attack

Attacker sends spoofed SYN packets containing the destination IP as the
source-IP address. Flooding a system with such empty connections can
overwhelm the system, causing DoS.
Use land-attack to drop packets containing the same IP address as both the
source and destination IP addresses.

ping-of-death

If the sum of "Fragment Offset" and "Total length" fields in the IP header of
each IP fragment is larger than 65,535, then the packet is invalid, and such
packet will be dropped.

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TABLE 13

128

Rules for common attack types and descriptions

fin-with-no-ack

TCP packets with a FIN flag normally have an ACK bit set.
Use fin-with-no-ack to drop TCP packet where FIN flag is set, but the ACK bit
is not set.

large icmp

ICMP packets greater than 1500 bytes.

unknown-ip-protocol 

Protocol 101 and above are currently reserved and undefined. Attackers
sometimes use protocol values that are not valid protocols.
Use unknown-ip-protocol  to drop packets where protocol field is set
to 101 or greater. Replace the  with the actual protocol number. If
the ServerIron ADX gets an IP protocol packet matching that number, the
packet will be dropped.

address-sweep 


Attacker scans the network for information behind the ServerIron ADX,
uncovering an address to target. For example, sending ping requests to
10.1.1.1 through 100. A reply from any device indicates a server exists.
Use address-sweep   to log the number of
different addresses being accessed from one remote source. If the same
client sends a request to different IP addresses, then the ServerIron ADX
keeps track of the number of IP address the client is trying to access. If the
number exceeds the configured  limit within a 5-second timer, then
all the packets from that client will start being dropped (reset) for the
specified . The timer is internal to the ServerIron ADX,
and it does not start when the client accesses the first IP address.
For example, consider the command address-sweep 2 8. A client can access
only a maximum of two IP addresses. As soon as it accesses the third IP
within a 5-second interval, the ServerIron ADX will hold the client down for 8
minutes. Accessing two IP addresses within 5 seconds is permissible in this
example.
Use security net-scan-mon-interval  to change the timer default
(5 seconds).

port-scan 


Attacker sends traffic using the same source IP to different ports on the
same destination IP, with the intent of identifying a service to target.
The ServerIron ADX tracks the number of IP destination and port pairs. For
example, if a client accessed IP 1 and port 0, that counts as one
.
Use port-scan to internally log the number of different ports scanned from
one source. If the number exceeds a configured  value
(for example, 10 ports in 5 seconds), the ServerIron ADX will flag it as an
attack and reject all traffic from that source for the .
The default internal timer value is 5 seconds. Use security
net-scan-mon-interval  to change the timer default.

xmas-tree

A Xmas tree attack is detected when a packet with the URG,PSH & FIN flags
set is detected.

icmp-type

Different types and subtypes of ICMP can be used to attack or to gain
knowledge about the host or network, which would then be used for an
attack. For example, ICMP timestamp (type 13) will elicit a timestamp reply
from Unix systems, but Microsoft Windows would not do so. A hacker can
then attack known vulnerabilities of the system.
Use icmp-type to configure an ICMP software rule to drop specific ICMP
types and subtypes.

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Configuring a rule for ip-option attack types
ServerIron ADX has a set of built-in rules to manage ip-option attack types. In this case, the rule
command is used with a  variable specified in Table 14.
The following example configures the "filter2" security filter with a rule to drop packets that are
associated with a ip-option record-route attack.
ServerIronADX(config)# security filter filter2
ServerIronADX(config-sec-filter2)#rule ip-option record-route drop

Syntax: [no] rule ip-option  [log | no-log] [drop | no-drop]
The  variable is specified as one of the options described in Table 14.
The log parameter directs the ServerIron ADX to log traffic on the bound interface that matches the
rule specified by the configured . The no-log parameter disables this
function.
The drop parameter directs the ServerIron ADX to drop traffic on the bound interface that matches
the rule specified by the configured . The no-drop parameter disables this
function

TABLE 14

ip-option attack types and descriptions

Attack Type

Description

ip-option record-route

The record-route option records the path of the packet, which an attacker
can analyze to learn details about a network’s addressing scheme and
topology.
Use ip-option record-route to drop packets with IP option 7 (record route) set.

ip-option strict-source-route

The strict-source option provides a means for the source of a packet to
supply routing information to the gateways forwarding the packet to the
destination, and to record the route information.
With this option, an attacker can gain knowledge on the network’s
addressing scheme.
Use ip-option strict-source-route to drop packets having IP option 9 (strict
source routing).

ip-option loose-source-route

The loose-source option provides a means for the source of the packet to
supply routing information to be used by the gateways in forwarding the
packet to the destination.
This option is different from strict-source route because gateway or host IP is
allowed to use any route of any number of other intermediate gateways to
reach the next address in the route. With this option, an attacker can gain
knowledge on the network’s addressing scheme.
Use ip-option loose-source-route to drop packets that have IP option 3 (loose
source routing).

ip-option timestamp

Use ip-option timestamp to drop packets where IP option list includes option
4 (Internet timestamp).

ip-option stream-id

The stream-ID option provides a way for the 16-bit SATNET stream identifier
to be carried through networks that do not support the stream concept.
Use ip-option stream-id to drop packets where the IP option is 8 (stream ID).

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Configuring a rule for icmp-type options
ServerIron ADX has a set of built-in rules to manage icmp-type options. In this case, the
rule-icmp-type command is used with a  variable specified in Table 15.
The following example configures the "filter3" security filter with a rule to drop packets that contain
the icmp-type echo-reply type.
ServerIronADX(config)# security filter filter3
ServerIronADX(config-sec-filter3)# rule icmp-type echo-reply drop

Syntax:

[no] rule icmp-type  [log | no-log] [drop | no-drop]

The  variable can be one of the options described in Table 15
The log parameter directs the ServerIron ADX to drop traffic on the bound interface that matches
the rule specified by the configured . The no-log parameter disables this function.
The drop parameter directs the ServerIron ADX to drop traffic on the bound interface that matches
the rule specified by the configured . The no-drop parameter disables this function

TABLE 15

icmp option types and descriptions
ICMP Option Type

Description

icmp-type addr-mask

icmp type 17: addr-mask
timestamp-reply
icmp type 14: timestamp-reply

icmp-type addr-mask-reply

addr-mask-reply: icmp type 18: addr-mask-reply

icmp-type destination 

icmp type 3: destination-unreachable.
The  variable is specified as one of the following values.

i

130

admin-prohibit
fragment-needed
host-admin-prohibited
host-precedence-violation
host-unknown
host-unreachable
host-unreachable-for-tos
net-admin-prohibited
net-unknown
net-unreachable
network-unreachable-for-tos
port-unreachable
precedence-cutoff
protocol-unreachable
route-fail
source-host-isolated

code 13: admin-prohibit
code 4: fragment-needed
code 10: destination-host-admin-prohibited
code 14: host-precedence-violation
code 7: destination-host-unknown
code 1: host-unreachable
code 12: host-unreachable-for-tos
code 9: destination-network-admin-prohibited
code 6: net-unknown
code 0: network-unreachable
code 11: network-unreachable-for-tos
code 3: port-unreachable
code 15: precedence-cutoff-in-effect
code 2: protocol-unreachable
code 5: route-fail
code 8: source-host-isolate

icmp-type echo-reply

icmp type 0: echo-reply

icmp-type echo-request

icmp type 8: echo-request

icmp-type info-reply

icmp type 16: information-reply

icmp-type info-request

icmp type 15: information-request

icmp-type param-problem

icmp type 12: parameter-problem

icmp-type redirect

icmp type 5: redirect

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icmp option types and descriptions
icmp-type router-advertisement

icmp type 9: router-advertisement

icmp-type r outer-selection

icmp type 10: router-selection

icmp-type source-quench

icmp type 4: source-quench

icmp-type time

icmp type 11: time-exceeded

icmp-type timestamp

icmp type 13: timestamp

icmp-type timestamp-reply

icmp type 14: timestamp-reply

Configuring a rule for IPv6 ICMP types
ServerIron ADX has a set of built-in rules to manage IPv6 icmp types. In this case, the rule
command is used with a  variable specified in Table 16.
The following example configures the "filter4" security filter with a rule to drop packets that
acontain the icmpv6-option type echo-reply.
ServerIronADX(config)# security filter filter4
ServerIronADX(config-sec-filter4)#rule icmp-type echo-reply drop

Syntax: [no] rule ip-option  [log | no-log] [drop | no-drop]
The  variable is specified as one of the options described in Table 16.
The log parameter directs the ServerIron ADX to drop traffic on the bound interface that matches
the rule specified by the configured . The no-log parameter disables this function.
The drop parameter directs the ServerIron ADX to drop traffic on the bound interface that matches
the rule specified by the configured . The no-drop parameter disables this function

TABLE 16

ICMPv6 types and descriptions

Attack Type

Description

cpa

ICMP type 149: Certification Path Advertisement.

cps

ICMP type 148: Certification Path Solicitation

echo-reply

ICMP type 129: echo-reply

echo-request

ICMP type 148: echo-request

mra

ICMP type 151: Multicast Router Advertisement

mrs

ICMP type 152: Multicast Router Solicitation

mrt

ICMP type 153: Multicast Router Termination

neighbor-advertisement

ICMP type 136: neighbor-advertisement

neighbor-solicitation

ICMP type 135: neighbor-solicitation

private

ICMP type 200: Private experimentation

private1

ICMP type 201: Private experimentation

redirect-message

ICMP type 137: redirect-message

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TABLE 16

ICMPv6 types and descriptions

reserved

ICMP type 255: reserved for expansion

router-advertisement

ICMP type 134: router-advertisement

router-solicitation

ICMP type 133: router-solicitation

Configuring a rule for IPv6 ext header types
ServerIron ADX has a set of built-in rules to manage IPv6 header types. In this case, the rule
command is used with a  variable specified in Table 17.
The following example configures the "filter5" security filter with a rule to drop packets that contain
the ipv6-ext-header type esp.
ServerIronADX(config)# security filter filter5
ServerIronADX(config-sec-filter5)#rule ipv6-ext-header-type esp drop

Syntax: [no] rule ipv6-ext-header-type  [log | no-log] [drop | no-drop]
The  variable is specified as one of the options described in Table
17.
The log parameter directs the ServerIron ADX to drop traffic on the bound interface that matches
the rule specified by the configured . The no-log parameter disables
this function.
The drop parameter directs the ServerIron ADX to drop traffic on the bound interface that matches
the rule specified by the configured . The no-drop parameter
disables this function

TABLE 17

132

IPv6 ext header types and descriptions

Attack Type

Description

ah

Authentication Header Option

cfg-hdr0-num

Configurable extension header code 0

cfg-hdr1-num

Configurable extension header code 1

cfg-hdr2-num

Configurable extension header code 2

cfg-hdr3-num

Configurable extension header code 3

destination-option

Destination Options (with Routing Options)

esp

Encapsulation Security Payload Header

hop-by-hop

Hop-by-Hop option

mobility-header

Mobility Header option

no-next-header

No Next Header

routing-header

Routing Header option

unknown-header

Unknown headers are those that are not listed in the above header types
and TCP/UDP/ICMPv6.

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Binding the filter to an interface
To implement a filter, it must be bound to an interface. It will then be applied globally to all
interfaces on the ServerIron ADX. To bind a filter to an interface, use the following command:
ServerIronADX(config-if-e1000-1/2)# security apply-filter filter1

Syntax: security apply-filter 
The  variable specifies filter that you want to apply on the ServerIron ADX. A maximum
or 10 filters can be bound to a single interface.

Clearing DOS attack statistics
Use clear statistics dos-attack to reset counters for ICMP and TCP SYN packet burst thresholds.
Syntax: clear statistics dos-attack

Clearing all DDOS Filter & Attack Counters
Use security clear all-dos-filter-counters to reset all DDOS Filter and Attack Counters.
Syntax: security clear all-dos-filter-counters

Logging for DoS attacks
Use the show log command to display the logging information and notice the attack type hits:
For each log event taking place for software rules, the ServerIron ADX sends a syslog message and
an SNMP trap. The system logs every 1 second time period, but only the difference is logged (not
cumulative totals). For example, assume 5 packets are dropped within 1 second. The system logs
5. Then, 2 packets are dropped during the next second. The system logs 2 (not 7).
Use show security hold:
Use show security net-scan-sessions:
BP # show sec net-scan-sessions 
IP address
Attack Type
Number Scanned
10.10.1.101->10.10.1.151
port-scan
1

The number scanned indicate the number of ports client 10.10.1.101 has accessed on IP
10.10.1.151 (which is the VIP in the example).
Similarly for address-sweep:
BP #show sec net-scan-sessions 0
IP address
10.10.1.101

Attack Type
address-sweep

Number Scanned
2

The above example tells you that client 10.10.1.101 has accessed 2 destination IPs in the past 1
monitoring interval.

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Displaying security filter statistics
You can display security filter statistics as shown.
ServerIronADX# show security filter-statistics
Filter
|Type
|Log Cnt
|Drop Cnt
dos-filter
|icmp-type
|0
|0
Cumulative Statistics
attack-type = log-count,
ip-options
= 0,
icmp-type
= 0,
address-sweep
= 0,
port-scan
= 0,
generic
= 0,
filter-dns
= 0,

drop-count
0
0
0
0
0
0

Attack-type = Attack-count
ipv6-ext-header
= 1201
icmpv6-type-All
= 321
icmpv6-type-NS
= 221
icmpv6-type -NA
=
60
icmpv6-type-RS
=
24
icmpv6-type-RA
=
16
large-icmp
=
0
unknown-ip-proto
=
0
xmas-tree
=
0
tcp-no-flags
=
0
syn-fragments
=
0
syn-and-fin-set
=
0
deny-all-fragments =
0
fin-with-no-ack
=
0
icmp-fragment
=
0
land-attack
=
0
ping-of-death
=
0

The counters shown for the show security filter-statistics command display the DDoS attack types
and the number of packets that have been counted, logged or dropped for each type.
Syntax: show security filter-statistics

Address-sweep and port-scan logging
The ServerIron ADX provides a log message for address-sweep and port-scan. When the ServerIron
ADX detects either of these attacks, the SSM CPU will send a message to the MP indicating the
particular IP will be held down for the specified time interval.
Log example:
Security: Address-sweep attack detected!Holdown 10.10.1.101 for 2 min

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Secure Socket Layer (SSL) Acceleration

6

ServerIron ADX supports integrated hardware-based SSL acceleration. This chapter describes how
to configure a ServerIron ADX for SSL acceleration in SSL Termination or SSL Proxy mode.
SSL support on the ServerIron ADX includes support for SSLv2, SSLv3, and TLS1.0.

SSL overview
The Secure Sockets Layer (SSL) protocol was developed by Netscape to provide security and
privacy between client and server over the Internet. SSL supports server and client certificate
verification, allowing protocols such as HTTP, FTP, and Telnet to be run on top of the verification
process. SSL negotiates encryption keys and authenticates the server before data is exchanged by
higher-level applications.
The SSL "handshake" is a key concept in this protocol. The handshake consists of two phases:
server authentication, and an optional client certificate verification. In server authentication, the
server sends its certificate and cipher preferences to a client that has made a request. The client
then generates a master key, encrypts it with the public key of the server, and returns the
encrypted master key to the server.
The server recovers the master key and authenticates itself to the client by returning a message
encrypted with the master key. Subsequent data is encrypted and authenticated with keys derived
from this master key. In the client certificate verification phase (which is optional), the server sends
a challenge to the client, who authenticates itself to the server by returning a digital signature with
its public-key certificate.
A variety of cryptographic algorithms are supported by SSL. During the "handshaking" process, the
DSA public-key cryptosystem is used. After the exchange of keys, a number of ciphers are used that
include RC4 and triple-DES for data encryption, and the SHA-1 and MD5 digest algorithm for
message authentication.

Public Key Infrastructure (PKI)
In cryptography, a public key infrastructure (PKI) is an arrangement that provides for trusted third
party vetting of, and vouching for, user identities. It also allows binding of public keys to users. This
is usually carried out by software at a central location, together with other coordinated software at
distributed locations. The public keys are typically in certificates.
The term PKI may mean both the certificate authority and related arrangements as well as, more
broadly (which can sometimes be confusing), the use of public key algorithms in electronic
communications. The latter meaning is erroneous since PKI methods are not required to use public
key algorithms.

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SSL overview

Asymmetric cryptography
This method alters information so that the key used for encryption is different from the key used for
decryption. Encrypted information is unintelligible to unauthorized parties.

Certificate Authority (CA)
The certificate authority (CA) issues and manages security credentials and public keys for message
encryption within a network.

Certificate Revocation List (CRL)
The CRL is a list of subscribers paired with their digital signature status, specifically any revoked
certificates and the reason for the revocation.

Cipher suite
A cipher specifies the suite of cryptographic algorithms to be used for key exchange, bulk
encryption, and message authentication.

Digital certificate
A digital certificate is a digital document that is generally stored and administered in a central
directory. It contains the certificate holder's name, a serial number, expiration dates, public key,
and the digital signature of the certificate issuing authority.

Digital signature
A digital (electronic) signature authenticates the identity of the sender, ensures that the original
content of the message is unchanged, is easily transportable, cannot be easily repudiated, cannot
be imitated, and can be automatically time stamped.

Key
When used in the context of cryptography, a key is a series of random numbers used by a
cryptographic algorithm to transform plaintext data into encrypted data, and vice versa.

Key pair
A pair of digital keys - one public and one private - used for encrypting and signing digital
information.

Private key
A cryptographic key known only to the user, employed in public key cryptography in decrypting or
signing information. One half of a key pair.

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Public key
The other half of a key pair, a public key is held in a digital certificate. Public keys are usually
published in a directory. Any public key can encrypt information; however, data encrypted with a
specific public key can only be decrypted by the corresponding private key.

NOTE
We recommend that you always back up your SSL certificate keys. These keys may be lost in the
event of module failure.

SSL acceleration on the ServerIron ADX
The ServerIronADX SSL module provides hardware-accelerated encryption and decryption services
to clients. The ServerIronADX sits between clients and servers and all client traffic is terminated on
the switch. When traffic is decrypted, the ServerIronADX analyzes the data and selects a server
where the connection traffic can be forwarded. The ServerIronADX then opens a new connection to
the server and passes all data to this server. On the return path, the ServerIronADX receives all
data from the server, encrypts it, and forwards it to the client. For every incoming connection from
the client, the ServerIronADX maintains an additional connection to the server. Both connections
are completely separate. The ServerIron ADX essentially acts as a proxy.
SSL acceleration on the ServerIron ADX can be configured to operate in either of the following two
modes:

• SSL Termination Mode – In SSL Termination mode, an SSL connection is maintained between
a client and a ServerIron ADX. The connection between the ServerIron ADX and the server is
not encrypted.

• SSL Full Proxy Mode – In SSL Full Proxy mode, one SSL connection is maintained between a
client and a ServerIron ADX and a separate SSL connection is maintained between a
ServerIron ADX and a server. This connection allows for traffic encryption to be maintained all
the way from the client to the server and back.
For details on how to configure a ServerIronADX for SSL Termination and Proxy modes, see
Configuring Real and Virtual Servers for SSL Termination and Proxy Mode 172 and for examples of
how to create the configurations shown in this section see Configuration Examples for SSL
Termination and Proxy Modes 176.

SSL Termination Mode
In this mode, the ServerIron ADX terminates the SSL connections, decrypts the data, and sends
clear text to the server. The ServerIron ADX offloads the encryption and decryption services from
the server CPU and performs them in hardware, thereby offloading the burden from the server.
The ServerIronADX maintains an encrypted data-channel with the client and a clear-text data
channel with the server.
Figure shows a topology that terminates SSL on the ServerIron ADX.

FIGURE 9

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SSL acceleration on the ServerIron ADX

Real
Server

Client

rs10 (10.1.1.20)

ServerIron
SSL
Traffic

SSL Termination on:
vip 10 (10.1.1.100)

(encrypted)

HTTP
Traffic
(unencrypted)

SSL Proxy Mode
In full SSL proxy mode, a ServerIronADX maintains encrypted data channels with the client and
server. The ServerIronADX maintains an SSL session with the client and a separate one with the
server. This maintains total SSL security between client and server.
This is useful in a configuration where you want to maintain full SSL security between a client and
server and also have the ServerIronADX perform L7 processing and security to application traffic.
This works because after the SSL connection is terminated at the ServerIronADX and before it
enters the SSL connection with the server, it is in clear-text within the ServerIronADX where it can
be subject to L7 inspection.
Figure 10 shows the basic topology for a configuration of the full SSL proxy mode.

FIGURE 10

ServerIron ADX SSL Proxy

Real
Server

Client

rs10 (10.1.1.20)

ServerIron
SSL
Traffic
(encrypted)

SSL Proxy on:
vip7 (10.1.1.30)

SSL
Traffic
(encrypted)

ServerIron ADX SSL
This section describes the SSL features used in configuration of a ServerIron ADX for SSL
acceleration.

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ServerIron ADX keypair file
The keypair file specifies the location for retrieving the SSL asymmetric key pair, during an SSL
handshake. You can create a keypair file by generating a key pair locally on the ServerIron ADX or
import a pre-existing key pair, using secure copy (SCP).The key pair is stored in the flash memory
and is not deleted during a power cycle. The ServerIron ADX supports keys in PEM (Privacy
Enhanced Mail) or PKCS12 (Public Key Cryptography Standard 12) formats.

NOTE

ServerIronADX supports keys in PEM (Privacy Enhanced Mail) or PKCS12 (Public Key Cryptography
Standard 12) formats.

Digital certificate
A digital (electronic) signature authenticates the identity of the sender, ensures that the original
content of the message is unchanged, is easily transportable, cannot be easily repudiated, cannot
be imitated, and can be automatically time stamped. The certificate contains the public part of the
RSA key, which must be the same as the key in the keypair file. The public key used in the
certificate file must match the key pair that is associated with the profile.
If the public key of the certificate does not match the key pair defined under the profile, the
ServerIron ADX does not accept the connection.
If the public key in the certificate file does not match the key in the keypair file, a ServerIron ADX
does not accept the command and displays the following error message:
"Error reading certificate from file "

The certificate file specifies the location for retrieving the digital certificate the ServerIron ADX
presents to the client for every new SSL handshake request. The certificate is stored in the flash
memory, and is not deleted upon a power cycle.
You can create a certificate file locally or you can import it. You can also generate a Certificate
Signing Request (CSR) and have it signed by a known CA to create a certificate and then import it.
See the section "certificate management" for an overview of each process.
Chained certificates
In an ideal world, a Certificate Authority signs and issues a certificate directly to a server. The
server loads this certificate and whenever a client makes a connection to it, this certificate is
presented. The client already has a copy of the CA's public certificate and verifies the server
certificate against it.
For manageability and security reasons, CAs may not sign server certificates directly. Many times,
the root CA signs an intermediate CA that in turn signs the server certificates. When this happens,
a certificate chain is created. There can be multiple levels of intermediate CA certificates.
Three level chain
• CA ----> 1st level Intermediate CA ----> server certificate
Four level chain
• CA ---> 1st level Intermediate CA ---> 2nd level Intermediate CA ---> server certificate
The end clients, including Mozilla, Firefox and Internet Explorer, always have a copy of the
well-known parent CA's certificate. They, however, may not have the intermediate CA's certificates.

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Configuring SSL on a ServerIron ADX

Configuring SSL on a ServerIron ADX
When configuring a ServerIron ADX for either SSL Termination mode or SSL Proxy mode, you must
perform each of the following configuration tasks:

• Obtain a Keypair File – This section describes how to obtain an SSL asymmetic key pair. You
can generate an RSA key pair or import an existing key pair. See “Obtaining a ServerIron ADX
keypair file” on page 140.

• Certificate Management – This section describes various methods for obtaining a digital
certificate and the methods for importing Keys and Certificates. See “Certificate management”
on page 141.

• Basic SSL Profile Configuration – This section describes how to perform the minimum SSL
profile configuration. See “Basic SSL profile configuration” on page 164.

• Advanced SSL Profile Configuration – This section describes additional SSL profile
configuration parameters. See “Advanced SSL profile configuration” on page 166.

• Configure Real and Virtual Servers for SSL Termination and Proxy Mode – This section
describes the configuration details required to configure the Real and Virtual servers for SSL
on a ServerIron ADX. See “Configuring Real and Virtual Servers for SSL Termination and Proxy
Mode” on page 172.

• Configuring Other Protocols with SSL– This section describes how to configure other popular
protocols such as LDAPS, POP3S and IMAPS with SSL acceleration. See “Other protocols
supported for SSL” on page 184

• Configure System Max Values – This section describes how to configure system max values for
SSLv2 connection rate and memory limit for SSL hardware buffers. See “Configuring the
system max values” on page 185.

Obtaining a ServerIron ADX keypair file
The keypair file specifies the location for retrieving the SSL asymmetric key pair, during an SSL
handshake. You can either generate an RSA keypair file on a ServerIron ADX or import a
pre-existing key pair, using secure copy (SCP).The key pair is stored in the flash memory and is not
deleted during a power cycle.
To generate an RSA keypair file, enter the following command.
ServerIronADX# ssl genrsa rsakey-file 1024 mypassword

Syntax: ssl genrsa   
The  variable specifies the name of the keypair file. The file name can be up to 24
characters in length. The file name supports special characters like ’-’,’ _’, ’$’, ", ’%’, ’&’, and ’!’. It
does not support spaces and ’/’ characters.
The  variable specifies the Key strength (number of bits) for the RSA key pair. The
RSA key strength should be 512, 768, 1024 or 2048.

NOTE
The ServerIron ADX does not support key strength greater than 2048 bits.
The  variable specifies the password to the file. The length of password should not
exceed 64 characters.

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Once a key pair is generated it can be saved for backup on your server by exporting it as described
in “Importing keys and certificates” on page 148.
Also, you can import a keypair file (instead of generating it) as described in “Importing keys and
certificates” on page 148.

NOTE

The ServerIron ADX supports keys in PEM (Privacy Enhanced Mail) or PKCS12 (Public Key
Cryptography Standard 12) formats.

Certificate management
All configuration options used with the SSL acceleration features of the ServerIron ADX require that
you obtain a Certificate and upload it to the system. The following methods can be used to obtain
as certificate.

• “Generating a Self-Signed Certificate” on page 141
• “Using CA-signed certificates” on page 142
• “Exporting Web Server Certificates” on page 143
Once a digital certificate and a keypair are obtained you can Import them to the ServerIron ADX
using the procedures described in “Importing keys and certificates” on page 148. This section also
describes how to configure a list of certificates that have been revoked by a CA in “Importing keys
and certificates” on page 148.

Generating a Self-Signed Certificate
Before generating a self-signed certificate, you must obtain an RSA key pair as described in
Obtaining a ServerIron ADX keypair file 140
Once you’ve obtained the RSA key pair, you can generate a self-signed certificate as shown in the
following example.
ServerIronADX# ssl gencert certkey testkey signkey testkey brocade123 testcert
You are about to be asked to enter information that will be incorporated into
your certificate request. The information you enter is what is called a
Distinguished Name or a DN.
Country name (2 letter code) [US] US
State or province (full name) [Some state] TX
Locality name (city) [Some city] Dallas
Organization name (Company name) Brocade
Organizational unit name (department) Engineering
Common name (your domain name) www.brocade.com
Email address [webadmin@brocade.com] se@brocade.com

Syntax: ssl gencert certkey  signkey   
The  variable is the name of the RSA key pair used to build and sign this certificate. It
is created using the ssl genrsa command.
The  variable is the password that is used to store this certificate.
The  variable is the filename used to store the generated certificate. This file name
can contain a maximum of 32 characters.

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NOTE

To export a certificate off of a ServerIron ADX you need the key-pair-file and password configured
here.

NOTE

To generate a self signed certificate, the certkey and sign key must be the same.

Using CA-signed certificates
Before generating a CA-signed certificate, you must obtain an RSA key pair as described in
“Obtaining a ServerIron ADX keypair file” on page 140.
Once you’ve obtained the RSA key pair, you can create a certificate signing request (CSR) as shown
in the following example.
ServerIronADX# ssl gencsr testkey
You about to be asked to enter information that will be incorporated into
your certificate request. What you are about to enter is what is called a
Distinguished Name or a DN.
Country name (2 letter code) [US] US
State or province (full name) [Some state] Texas
Locality name (city) [Some city] Dallas
Organization name (Company name) [Brocade Communications] Brocade
Communications
Organizational unit name (department) [Web administration] Engineering
Common name (your domain name) [www.brocade.com] www.brocade.com
Email address [webadmin@foundrynet.com] se@brocade.com
-----BEGIN CERTIFICATE REQUEST----MIIBszCCARwCAQAwczELMAkGA1UEBhMCVVMxEzARBgNVBAgTCkNhbGlmb3JuaWEx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-----END CERTIFICATE REQUEST-----

The output above, between BEGIN CERTIFICATE REQUEST and END CERTIFICATE REQUEST
is a certificate signing request and registration. It is called a Base-64-encoded CSR.
The certificates that you import into the ServerIron will need to be in Base-64 encoding as
well. The ServerIron accepts certificates in the .PEM and .P12 format. These formats are
described further in this document as well as how to convert between formats.
You need to copy the certificate signing request mentioned above and register it with a
trusted certificate authority; for example, Verisign. They will issue you a server certificate,
based on this request (which will include the intermediate and root certificates).
You will then need to import these certificates into the ServerIron via SCP from a remote
machine. Again, the certificates you import must be in Base 64 encoding. You can quickly
tell if this is the case by opening the certificate in notepad. It should look like this:
-----BEGIN CERTIFICATE-----

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MIIDKTCCApKgAwIBAgIRAJoKUHAGHghM4kW84LNXP1wwDQYJKoZIhvcNAQEFBQAw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-----END CERTIFICATE-----

Syntax: ssl gencsr 
The  variable is the key name that you want to use for the certificate request.

Exporting Web Server Certificates
You can export a Web Server Certificate from a Web server and install it on a ServerIronADX. This
section describes the procedures required to export Web server certificates from a Windows
Internet Information server (IIS), or and Apache server (UNIX).
Windows IIS
To export an existing Web server certificate to install on a ServerIronADX, follow these steps:
1. In the Run dialog box, type mmc, and click OK. The Microsoft Management Console (MMC)
appears.
2. If you do not have Certificate Manager installed in MMC, you need to install it. For more
information on how to add the Certificate snap-in to an MMC console, see the Microsoft link:
Install a Server Certificate.
3. In the console tree, click the logical store where the certificate you want to export exists. It is
usually in the Certificates folder in the Personal directory under Certificates (local computer)
on the console root.
4. Right-click the certificate you want to export and click All Tasks > Export to start the Certificate
Export Wizard.
5. Click Next.
6. On Export Private Key, click Yes to export the private key.
You must export the private key with your certificate for it to be valid on your target server.
Otherwise, you must request a new certificate for the target server.
7.

In the Export File Format dialog box, choose.PFX. If the certificate has already been formatted,
that format is selected as the default. Click Next.
Do not select Delete the private key if export is successful, because this disables the SSL site
that corresponds to the private key.

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8. Continue to follow steps in the wizard, and enter a password for the certificate backup file
when prompted. Using a strong password is highly recommended to ensure that the private key
is well protected.
9. Type the name of the file you want to export, or click Browse to search for the file. Click Next.
10. Click Finish to exit the Certificate Export Wizard.
In order for certificates to be imported into the ServerIron ADX, they must be in a specific format.
The .PFX file must be converted to .PEM or .P12. Procedures for converting certificate formats are
described in “Converting certificate formats” on page 147.

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11. When prompted for the import password, enter the password you used when exporting the
certificate to a PFX file. You should receive a message that says MAC verified OK. The resulting
file contents will resemble the following:

1.3.6.1.4.1.311.17.2: 
localKeyID: 01 00 00 00
Microsoft CSP Name: Microsoft RSA SChannel Cryptographic Provider
friendlyName: 740b399c4eb957ca6b972da9345dbda3_e7adefb8-6420-4ed2b6f5-2c4988094b69
Key Attributes
X509v3 Key Usage: 10
-----BEGIN RSA PRIVATE KEY----MIICWwIBAAKBgQCrSx5QmEBB35QZqKZLzt9uC9ZPmL8sNI/yNfDlh0BnT3Y0xcxV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-----END RSA PRIVATE KEY----Bag Attributes
localKeyID: 01 00 00 00
friendlyName: www.brocade.com
subject=/C=US/ST=Texas/L=Dallas/O=Brocade/OU=Engineering/CN=www.brocade.com
issuer=/DC=com/DC=brocade/O=Brocade/OU=Engineering/CN=www
-----BEGIN CERTIFICATE----MIICxTCCAi6gAwIBAgIQDmM2IYR4YnLzCLr31Z/DPzANBgkqhkiG9w0BAQUFADBm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-----END CERTIFICATE-----

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Bag Attributes: 
subject=/DC=org/DC=test/O=root/OU=Security/CN=root
issuer=/DC=org/DC=test/O=root/OU=Security/CN=root
-----BEGIN CERTIFICATE----MIIC1TCCAj6gAwIBAgIQJhB5wR9FdbXPEWcLp/1MAjANBgkqhkiG9w0BAQUFADBm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-----END CERTIFICATE-----

12. You can now begin copying the certificates and the key pair files to the ServerIronADX (in the
following order):
scp ./server-key.pem admin@192.168.1.1:sslkeypair:server-key:foundry:pem
scp ./server-cert.cer admin@192.168.1.1:sslcert:certchain1:pem

Unix (Apache)
The following procedure describes the procedure for determining the location of the private key and
certificate files and copying them to a ServerIronADX.
1. On the Apache server, look in the httpd.config file for the following directives; they point to the
location of the key and certificate files:
SSLCertificateFile .../path/to/mycertfile.crt
SSLCertificateKeyFile .../path/to/mykeyfile.key

NOTE

The default location of the httpd.config file is: /etc/httpd/conf/httpd.conf
2. When you have located the key and certificate files, copy them from the Linux server to the
ServerIronADX:
scp ./server-key.key admin@192.168.1.1:sslkeypair:server-key:foundry:pem
scp ./server-cert.crt admin@192.168.1.1:sslcert:certchain1:pem
scp ./root-cert.crt admin@192.168.1.1:sslcert:certchain1:pem

Make sure you upload in the same order as the CA hierarchy – only then can the chain be
established properly on the ServerIron.

NOTE

You must upload all of the chain certificates into the same file on the ServerIronADX.

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Converting certificate formats
The ServerIronADX accepts server certificates in the PEM or PKCS12 format. The following sections
describe how to convert between the two formats and from PFX to the two formats using OpenSSL.
You can download a Win32 distribution of OpenSSL at the following location:
http://gnuwin32.sourceforge.net/packages/openssl.htm
Converting PEM to PKCS12
Use the open-source utility OpenSSL to perform the conversion from .PEM to .P12 as described in
the following
1. If you do not have it installed, download and install the Win32 OpenSSL package from the URL
described under “Converting certificate formats”.
2. Create a folder named C:\certs and copy the file pemkey.pem (private key file) and
pemcert.pem (certificate file) into this folder
3. Open a command prompt and move to the GnuWin32\bin directory:
cd %ProgramFiles%\GnuWin32\bin

4. Enter the following command to convert the PEM file to an P12 file (all on one line):
openssl pkcs12 –export –out c:\certs\mycert.p12 –name “My Certificate” –inkey
c:\certs\pemkey.pem –in c:\certs\pemcert.pem

5. When prompted for the import password, enter the password you used when exporting the
PEM certificate.
6. When prompted for a pass phrase, enter a password you want to use to protect the private key.
Converting PKCS12 to PEM
To convert a P12 file to a PEM file, follow these steps on a Windows machine:
1. If you do not have it installed, download and install the Win32 OpenSSL package from the URL
described under “Converting certificate formats”.
2. Create a new folder named C:\certs and copy the file pkcsfile.p12 into this folder
3. Open a command prompt and move to the GnuWin32\bin directory.
cd %ProgramFiles%\GnuWin32\bin

4. 4. Enter the following command to convert the P12 file to an PEM file:
openssl pkcs12 -in c:\certs\pkcsfile.p12 -clcerts -out c:\certs\pemfile.pem

5. When prompted for the import password, enter the password you used to export the PEM
certificate.
6. When prompted for a pass phrase, enter a password to protect the private key. This creates a
single .PEM file that includes both the private key and certificate.
7.

You can then separate the private key and certificate into separate .PEM files.

Use the open-source utility OpenSSL to perform the conversion from .PFX to .PEM (or .PFX to .P12).
You can download a Win32 distribution of OpenSSL at the following location:
http://gnuwin32.sourceforge.net/packages/openssl.htm

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Converting a PFX file to a P12 file
To convert a PFX file to a P12 file on a Windows machine, change the extension from .PFX to .P12
Converting a PFX file to a PEM file
To convert a PFX file to a PEM file on a Windows machine, follow these steps:
1. If you do not have it installed, download and install the Win32 OpenSSL package from the URL
described under “Converting certificate formats”.
2. Create a folder C:\certs and copy the file yourcert.pfx into the c:\certs folder
3. Open a command prompt and change into the GnuWin32\bin directory:
cd %ProgramFiles%\GnuWin32\bin

4. Type the following command to convert the PFX file to an unencrypted PEM file (all on one line):
openssl pkcs12 -in c:\certs\yourcert.pfx -out c:\certs\yourcert.pem –nodes

Importing keys and certificates
You can import keys and certificates to and from a ServerIron ADX. Generally you export a CSR
(certificate signing request) from a ServerIron ADX, have it signed by a CA, and import it back into
the ServerIron ADX.
You also need the import and export functionality if you want to use client-authentication to
transfer the CA certificate to a ServerIron ADX.
The ServerIron ADX supports SCP protocol for transferring keys and certificates. An internal SCP
server is provided and must be enabled before any transfer. A ServerIron ADX only responds to
transfer requests initiated by remote clients.
Enabling an SCP server
The SCP server relies on the SSH protocol. SCP is enabled by default. But, you need to enable SSH
first to generate the SSH key.
If the SSH server is not enabled, take the following steps to enable it.
1. Configure a domain name as shown. In this example, "www.mydomain.com" is configured as
the domain name.
ServerIronADX(config)# ip dns domain-name www.mydomain.com

2. Create a username. In this example, "secret" is configured as the username.
ServerIronADX(config)# username admin password secret

3. Enable SCP.
ServerIronADX(config)# crypto key generate dsa

4.

Allow empty SSH passwords.
ServerIronADX(config)# ip ssh permit-empty-passwd ye

Detailed descriptions of the commands used in this procedure are described in the following
manual: ServerIron ADX Administration Guide.

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Windows Users
GUI-based SCP tools do not work in the current environment when you use SCP to transfer the
certificate files to the ServerIronADX. Windows users should have PSCP, a free SCP utility based on
putty SSH client. To access this Windows utility, use the following commands:
C:\images>pscp first.cer admin@200.100.100.2:sslcert:bs:pem
C:\images>pscp second.cer admin@200.100.100.2:sslcert:bs:pem

To upload a key-pair to a ServerIron ADX:
Syntax: pscp 
@:sslkeypair:::
To download a key-pair from a ServerIron ADX:
Syntax: pscp @:sslkeypair:::

To upload a certificate file to a ServerIron ADX:
Syntax: pscp  @:sslcert::
To download a certificate file from the ServerIron ADX:
Syntax: pscp @:sslcert:: 
Example:
The following example uploads a certificate file named: "first.cert" to a ServerIron ADX and saves it
with the name "bs" in pem format:
C:\images>pscp first.cer admin@200.100.100.2:sslcert:bs:pem

Transferring a Keypair File and a Certificate File
For a ServerIron ADX to recognize the incoming file type, the filename must be in a specific format.
With the correct format, you can describe the file type, file name, password, and format.
The name is divided into fields, which are separated by colons (:). The following fields are used:

• File type - Determines whether the file contains a key pair or a certificate. The sslcert keyword
is used for a certificate. The sslkeypair keyword is used for a key pair.

• File name - The file name on the ServerIron ADX flash. The name cannot be more than 25
characters for the key pair file and 32 characters for the certificate file.

• Password - Only required for a keypair file password. It is not used in certificate files. The
password cannot be more than 64 characters.

• Format - Describes the format of the file. It can either be pem or pkcs12.
Based on these rules, use the following syntax to upload a file to ServerIronADX:
Syntax: scp   @::::

NOTE: You do not need the password field for PEM format certificate files.

NOTE
For example, if a keypair file, "myrsakeys" needs to be uploaded to ServerIron ADX, its password is
"brocade," and it is in PEM format. The SCP server is already enabled on the ServerIron ADX and a
user "admin" is also created.
To configure this scenario, use the following command:

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c:\ scp myrsakeys.pem admin@:sslkeypair:myrsakeys:brocade:pem

After uploading the keypair file, the same file can be downloaded to a client with the following
command:
c:\ scp admin@:sslkeypair:myrsakeys:foundry:pem myrsakeys.pem

NOTE
The downloaded file includes the following additional block of text at the end.
----BEGIN RSA PUBLIC KEY----MIGJAoGBANY8/gNKT42GTweT+/c34CRxRwmaUvQQbTMgxYhHdLbo1g+6sdDcrohH
IlXVOWJH4pjt9JB1zFaM/rSBnvKGkJ67HbT7dvszQnLNtg9aZnX3i5vPjFhjm9mj
j9E9alg/3CD1GpOXH40BJBZ3F8HFYaH8EOLlp5gLf/hxAYTPDQ2DAgMBAAE=
-----END RSA PUBLIC KEY----This additional block of text are the public key associated with the certificate, which does not create
any issues.
Similarly, a certificate file can be uploaded to or downloaded from the ServerIron ADX. For example,
to upload the certificate file "mycertfile" to the ServerIron ADX, which is in PEM format, use the
following command:
c:\scp mycertfile admin@:sslcert:mycertfile:pem

NOTE

There is no password field.
To download the same file from the ServerIron ADX back to the client, use the following command:
c:\ scp admin@:sslcert:mycertfile:pem

In general, use the following commands:

• To upload a key-pair to a ServerIron ADX:
Syntax: scp @:sslkeypair:::


• To download a key-pair from ServerIronADX:
Syntax: scp @:sslkeypair:::


• To upload a certificate file to the ServerIronADX:
Syntax: scp @:sslcert::

• To download a certificate file from the ServerIronADX:
Syntax: scp @:sslcert::
When a key-pair file or a certificate file is uploaded, you can view it using the show ssl cert
command described in “Displaying locally stored SSL certificates” on page 190.
Additional Notes for PKCS12
PKCS12 format stores keys and certificates in the same file. You must use the scp keyword
keypairfile and command syntax of keypairfile while transferring a PKCS#12 file to the
ServerIronADX.
To transfer a certificate and key file in PKCS format (mypkcsfile) to a ServerIron ADX, use the
following command:
c:\ scp ./mypkcsfile.p12 admin@:sslkeypair:mypkcsfile:brocade:pkcs12

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After transferring the file, it can be used both as a key and a certificate. To add the certificate file
and keys to the profile, use the following commands:
ServerIronADX(config-ssl-profile-mysslprofile)# keypair-file mypkcsfile
ServerIronADX(config-ssl-profile-mysslprofile)# certificate-file mypkcsfile

The show ssl cert command can be used to display a pkcs file. The show ssl key command does not
display a pkcs file, but it does contain a keypair.

Creating a Master Password for export of SSL keys
You can create a master password that grants permission to export all SSL keys on a ServerIron
ADX using SCP copy. This password is used with the "scp 
@: sslkeypair::: " command. If a master
password is not configured, a separate password associated with each key must be used.
To define a master password for the export of SSL keys, use the following command.
ServerIronADX# ssl set export-master-pswd exportpw

Syntax: ssl set export-master-pswd 
The  variable specifies the master password for export of SSL keys. It can be from 1 to
24 characters in length.
To disable a master password for export of SSL keys, use the following command.
ServerIronADX# ssl clear export-master-pswd exportpw

Syntax: ssl clear export-master-pswd 
The  variable specifies the master password for export of SSL keys that you want to
remove.
Use the following command to display whether a master password is in effect.
ServerIronADX# show ssl key *
master-password enable
ssl key files:
1
: key-test
2
: key1
3
: keyz
4
: keyc
5
: key7

Syntax: show ssl key *

Deleting certificate and key files
You can use the following commands to delete a specified certificate or key file as shown.
ServerIronADX# ssl clear certfile 

Syntax: ssl clear certfile 
The  variable specifies the certificate that you want to delete.
ServerIronADX# ssl clear keyfile 

Syntax: ssl clear certfile 
The  variable specifies the key that you want to delete.

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Certificate Verification
Every certificate has two very important fields: issuer (issued-by) and subject (issued-to). A CA’s
certificate has the same value in both fields, because the authority has issued a certificate to itself.
However, when the authority issues a certificate to a server, the issuer field contains the CA's
name, but the subject contains the server's name.
For example, the following server certificate was issued by Verisign (a CA):
Issuer: C=US, O=RSA Data Security, Inc., OU=Secure Server Certification Authority
Subject: C=US, ST=California, L=San Jose, O=Brocade Inc, OU=L47 and Security
Group, OU=Terms of use at www.verisign.com/rpa (c)05, CN=l47qa.foundrynet.com

To authenticate this server certificate, the client, for example, Firefox or IE, should have the
corresponding CA's certificate. When you open the trusted root CA page in Internet Explorer, you
can also see that entry has the same value in the issued by (issuer) and issued to (subject) fields.
This is an example of how a server certificate is issued directly by a CA. Note that in this scenario,
the server sends only its own certificate and not that of the CA.
Figure 11 shows a CA certificate.

FIGURE 11

152

Certificate

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Chained Certificate Verification
When the server certificate is not signed directly by the root CA, but signed by an intermediate CA,
as shown in the following example, there are two possible scenarios.

• CA ----> intermediate CA ----> server certificate
Client Already Has Intermediate CA's Certificate
In the first scenario, there are NO additional requirements. When the server sends a certificate that
is signed by the intermediate CA, the client browser will be able to process it successfully.
Client Does NOT Have Intermediate CA's Certificate
In the second scenario, the server sends a certificate that is signed by intermediate CA. However
since the end-client has no knowledge of the intermediate CA, it denies the certificate and the
process is unsuccessful.
To resolve this issue, the server must send not only its own certificate, but also the intermediate
CA's certificate that is signed the root CA. In other words, the server sends a chain of certificates.

NOTE
The server sends only its own certificate and the intermediate CA's certificate. It does NOT send the
root CA’s certificate.
Example

Your server certificate is signed by VeriSign International Server CA - Class 3. This is an
intermediate CA, whose certificate is signed by VeriSign Class 3 Public Primary CA.
Figure 12 shows the certificate hierarchy, with "L47.brocade.com" at the third level. The first level
certificate is also labeled as "built-in object token" by Firefox. This is an example of chaining. The
server sends a two-level chain containing its own certificate and the certificate of the intermediate
CA.
The certificate chain sent by the server must be correct: server-> intermediate CA. The
intermediate CA certificate must also be signed by a CA whose certificate is present with the client.
Figure 12 shows the certificate fields.

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FIGURE 12

Certificate Fields

There are two steps that will ensure that the chain is correct.
1. Verify that the issuer of the server certificate matches the subject of the intermediate CA's
certificate.
2. Verify that the issuer of the intermediate CA's certificate has an entry in the client's trusted
certificates.
For the first step, you must convert the certificate chain to a readable format. From the BP
console, use the show ssl cert  command to convert the chain to readable
format. All certificates in the chain are displayed and every certificate must begin with the
keyword certificate.
ServerIronADX# show ssl cert *
1 :verisign128cert
2 :cert2112.pem
3 :cert2031.pem
4 :cert4030
3 :cert2031

ServerIronADX# show ssl cert verisign128cert
Certificate:
Dat
Version: lu (0xlx)

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Serial Number:
70:2b:a7:4b:07:ea:29:99:5a:dc:3f:6f:74:da:39:6d
Signature Algorithm: sha1WithRSAEncryption
Issuer: O=VeriSign Trust Network, OU=VeriSign, Inc., OU=VeriSign
International Server CA - Class 3, OU=www.verisign.com/CPS Incorp.by Ref.
LIABILITY LTD.(c)97 VeriSign
Validity
Not Before: Nov 2 00:00:00 2005 GMT
Not After : Nov 2 23:59:59 2006 GMT
Subject: C=US, ST=California, L=San Jose, O=Brocade Inc, OU=Engineering,
OU=Terms of use at www.verisign.com/rpa (c)05, CN=L47.brocade.com
Subject Public Key Info:
Public Key Algorithm: rsaEncryption
RSA Public Key: (1024 bit)
Modulus (1024 bit):
00:a6:10:cc:70:dd:36:28:06:3c:c0:5f:c7:c0:44:
a6:54:cd:fc:2d:e3:a6:68:50:11:03:e5:e7:16:97:
f3:ba:b1:42:de:d0:df:26:f6:35:8f:22:a1:a4:3d:
fd:7a:35:08:ed:8c:5f:6c:ab:ca:13:1f:87:a0:c4:
dd:30:ea:00:18:b8:2b:24:25:13:60:c1:08:e4:af:
da:25:a9:e0:ef:c3:34:13:41:02:b2:39:83:1a:49:
bd:95:4e:29:3e:e9:a1:a4:d1:f9:0d:d1:80:3d:01:
ff:af:d2:a8:00:6a:2a:e2:97:cd:f5:5c:24:a4:88:
a2:a2:6f:da:1a:0d:8f:fa:f7
Exponent: lu IÕ8~0xlx)
*s:
*sX509v3 Basic Constraints:
*sCA:FALSE
*sX509v3 Key Usage:
*sDigital Signature, Key Encipherment
*sX509v3 Certificate Policies:
*sPolicy: 2.16.840.1.113733.1.7.23.3
*sCPS:
*sX509v3 CRL Distribution Points:
*sURI:http://SVRIntl-crl.verisign.com/SVRIntl.crl
*sX509v3 Extended Key Usage:
*sTLS Web Server Authentication, TLS Web Client Authentication, Netscape Server
Gated Crypto
*sAuthority Information Access:
*sOCSP - URI:http://ocsp.verisign.com
*sCA Issuers - URI:http://SVRIntl-aia.verisign.com/SVRIntl-aia.cer
*s1.3.6.1.5.5.7.1.12:
*s0_.].[0Y0W0U..image/gif0!0.0...+..............k...j.H.,{..0%.#http://logo.veris
ign.com/vslogo.gif
Signature Algorithm: sha1WithRSAEncryption
c8:65:15:64:42:ea:36:f4:d4:68:c4:ad:b9:1f:d9:03:fb:d9:
15:27:1b:f6:a2:e0:ea:ae:74:1e:de:94:17:36:0f:63:19:8f:
34:bf:f1:32:02:d5:c5:79:0d:bf:f8:56:62:34:67:4d:ad:b8:
40:e1:51:4f:2d:28:32:7f:20:ad:19:53:6b:6b:9e:c6:c1:50:
9e:89:fb:c1:f1:33:88:36:64:8a:28:d1:c3:1f:b4:c8:f8:c3:
af:5a:f2:77:86:67:3b:28:bb:84:17:a0:48:46:18:9b:f2:25:
a1:e3:74:f6:34:08:f0:ed:68:65:e5:89:27:07:94:df:0c:9b:
81:f5
Certificate:
Dat
Version: lu (0xlx)
Serial Number:
25:4b:8a:85:38:42:cc:e3:58:f8:c5:dd:ae:22:6e:a4

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Signature Algorithm: sha1WithRSAEncryption
Issuer: C=US, O=VeriSign, Inc., OU=Class 3 Public Primary Certification
Authority
Validity
Not Before: Apr 17 00:00:00 1997 GMT
Not After : Oct 24 23:59:59 2011 GMT
Subject: O=VeriSign Trust Network, OU=VeriSign, Inc., OU=VeriSign
International Server CA - Class 3, OU=www.verisign.com/CPS Incorp.by Ref.
LIABILITY LTD.(c)97 VeriSign
Subject Public Key Info:
Public Key Algorithm: rsaEncryption
RSA Public Key: (1024 bit)
Modulus (1024 bit):
00:d8:82:80:e8:d6:19:02:7d:1f:85:18:39:25:a2:
65:2b:e1:bf:d4:05:d3:bc:e6:36:3b:aa:f0:4c:6c:
5b:b6:e7:aa:3c:73:45:55:b2:f1:bd:ea:97:42:ed:
9a:34:0a:15:d4:a9:5c:f5:40:25:dd:d9:07:c1:32:
b2:75:6c:c4:ca:bb:a3:fe:56:27:71:43:aa:63:f5:
30:3e:93:28:e5:fa:f1:09:3b:f3:b7:4d:4e:39:f7:
5c:49:5a:b8:c1:1d:d3:b2:8a:fe:70:30:95:42:cb:
fe:2b:51:8b:5a:3c:3a:f9:22:4f:90:b2:02:a7:53:
9c:4f:34:e7:ab:04:b2:7b:6f
Exponent: lu IÕ8~0xlx)
*s:
*sX509v3 Basic Constraints:
*sCA:TRUE, pathlen:0
*sX509v3 Certificate Policies:
*sPolicy: 2.16.840.1.113733.1.7.1.1
*sCPS:
*sX509v3 Extended Key Usage:
*sTLS Web Server Authentication, TLS Web Client Authentication, Netscape Server
Gated Crypto, 2.16.840.1.113733.1.8.1
*sX509v3 Key Usage:
*sCertificate Sign, CRL Sign
*sNetscape Cert Type:
*sSSL CA, S/MIME CA
*sX509v3 CRL Distribution Points:
*sURI:http://crl.verisign.com/pca3.crl
Signature Algorithm: sha1WithRSAEncryption
08:01:ec:e4:68:94:03:42:f1:73:f1:23:a2:3a:de:e9:f1:da:
c6:54:c4:23:3e:86:ea:cf:6a:3a:33:ab:ea:9c:04:14:07:36:
06:0b:f9:88:6f:d5:13:ee:29:2b:c3:e4:72:8d:44:ed:d1:ac:
20:09:2d:e1:f6:e1:19:05:38:b0:3d:0f:9f:7f:f8:9e:02:dc:
86:02:86:61:4e:26:5f:5e:9f:92:1e:0c:24:a4:f5:d0:70:13:
cf:26:c3:43:3d:49:1d:9e:82:2e:52:5f:bc:3e:c6:66:29:01:
8e:4e:92:2c:bc:46:75:03:82:ac:73:e9:d9:7e:0b:67:ef:54:
52:1a

Once the chain is verified, the second step is to make sure that the intermediate CA is signed by a
root CA whose certificate already exists in the client.
In this example, the intermediate certificate is signed by:
Issuer: C=US, O=VeriSign, Inc., OU=Class 3 Public Primary Certification Authority

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Find and match this certificate in the list of trusted root certificates from the client browser.
Figure 13 shows the issuer certificate authority window.

FIGURE 13

Issuer Certificate Authority

Now the certificate chain is complete and the client browser will able to interpret it correctly. Let’s
consider another example with four level chain. Here, the root Certificate Authority is called as "OS
Level_0 CA". This CA has two intermediaries:

• “OS Level_1 CA” and “OS Level_2 CA”
The second level intermediate CA has signed a server certificate with the following CN "ServerCert
by Level_2":
OS Level_0 CA à OS Level_1 CAà OS Level_2 CA à ServerCert

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The certificate hierarchy is shown as under:
Level 0 (root)

issuer : CN=OS Level_0 CA
Subject : CN=OS Level_0 CA
Level 1 (first intermediary: Issuer : CN=OS Level_0 CA
Subject : CN=OS Level_1 CA
Level 2 (Second intermediary:Issuer : CN=OS Level_1 CA
Subject: CN=OS Level_2 CA
Level 3 (Server Certificate)Issuer: CN=OS Level_2 CA
Subject: CN=ServerCert by Level_2
ServerIronADX# show ssl cert l4chaincert
Certificate:
Dat
Version: lu (0xlx)
Serial Number: 3 (0x00000003)
Signature Algorithm: sha1WithRSAEncryption
Issuer: CN=OS Level_2 CA
Validity
Not Before: Feb 10 03:14:21 2006 GMT
Not After : Feb 8 03:14:21 2016 GMT
Subject: CN=ServerCert by Level_2, O=Foundry Nets, OU=L47QA
Subject Public Key Info:
Public Key Algorithm: rsaEncryption
RSA Public Key: (1024 bit)
Modulus (1024 bit):
00:bb:d1:5d:8d:5a:ac:0e:94:ec:6c:49:fa:0e:03:
cd:c1:84:52:f0:e6:be:5d:a8:d3:36:c0:33:19:67:
d9:d0:1a:27:87:68:ce:06:68:b1:35:53:64:01:27:
67:4a:69:6d:1f:6f:2e:99:0a:f2:85:ea:fb:1f:f0:
99:21:26:ff:f5:50:11:22:a6:55:cd:fa:b1:2f:be:
5d:cf:65:be:4d:1e:37:e1:64:46:69:c1:73:e5:de:
d5:1d:09:ef:f0:e7:fa:c3:b5:f1:90:21:d5:84:23:
24:8e:9d:f7:35:66:7e:c0:97:af:61:ee:5a:3e:31:
b6:a7:5f:b9:81:1d:0d:43:d9
Exponent: lu IÕ8~0xlx)
*sNetscape Cert Type:
*sSSL Server
*sX509v3 Key Usage:
*sDigital Signature, Non Repudiation, Key Encipherment
*sX509v3 Extended Key Usage:
*sTLS Web Server Authentication
*sNetscape CA Revocation Url:
*s
*sX509v3 Subject Key Identifier:
*s
*sX509v3 Authority Key Identifier:
*skeyid:23:77:98:42:E1:C1:BC:E7:9A:92:79:8E:DF:8D:C3:C1:2A:35:F2:0F
*sDirName:/CN=OS Level_1 CA
*sserial:01
*sAuthority Information Access:
*sCA Issuers - URI:http://s1.l47qa.com/l2/ca.crt
*sX509v3 CRL Distribution Points:
*sURI:http://s1.l47qa.com/l2/crl-v2.crl
*sX509v3 Certificate Policies:
*sPolicy: 1.1.1.1.1

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*sX509v3 Certificate Policies:
*sPolicy: 1.1.1.1.1
*sCPS:
*sUser Notice:
*sExplicit Text:
*sX509v3 Issuer Alternative Name:
*semail:root@s1.l47qa.com, URI:http://sq.l47qa.com
*sX509v3 Subject Alternative Name:
*s
Signature Algorithm: sha1WithRSAEncryption
8f:e0:08:8b:ea:69:9e:6b:45:d1:ef:e1:d0:ae:f5:74:9f:b7:
98:1a:83:fa:95:72:bf:d9:0c:91:b0:c4:e9:0a:e6:08:20:eb:
88:d9:b1:79:92:85:ce:26:6a:d5:31:d2:40:39:94:f0:58:6e:
29:24:ba:c8:f1:b0:dc:d9:80:c9:25:42:68:fa:e1:04:5b:e0:
c4:98:c9:61:97:2b:49:a8:74:ea:31:ee:7b:ec:ae:f0:8f:20:
32:b5:27:35:e0:dc:71:61:ed:ca:eb:31:bc:f4:27:46:78:a7:
41:00:ed:bc:9e:5c:e8:bc:fe:48:e2:77:3a:71:38:ea:b2:28:
3b:a3:44:54:f2:c5:f7:b3:f8:87:f7:5f:5e:3b:17:ce:97:9c:
d3:c6:52:26:1d:b0:98:4f:a3:ce:a8:17:d9:fb:da:22:6e:e5:
ee:8d:04:df:2c:bb:9f:3d:89:af:7f:07:aa:c2:82:89:a0:b1:
f0:42:a2:76:eb:d8:0c:9d:25:63:0f:46:f8:88:31:f8:a8:00:
00:96:10:df:5e:4f:f3:f4:49:a6:e6:85:97:96:ca:41:fd:c1:
55:26:e6:e8:df:ba:f6:63:01:85:36:3b:12:c9:e9:97:fc:fa:
8d:52:19:4e:e1:2e:46:32:ca:f8:2b:47:c0:46:27:b4:78:75:
be:64:df:6e
Certificate:
Dat
Version: lu (0xlx)
Serial Number: 1 (0x00000001)
Signature Algorithm: sha1WithRSAEncryption
Issuer: CN=OS Level_1 CA
Validity
Not Before: Feb 10 01:34:17 2006 GMT
Not After : Feb 10 01:34:17 2007 GMT
Subject: CN=OS Level_2 CA
Subject Public Key Info:
Public Key Algorithm: rsaEncryption
RSA Public Key: (2048 bit)
Modulus (2048 bit):
00:a4:5f:c5:0f:cf:9b:05:b6:b2:31:16:bb:b1:c2:
be:35:58:a7:8b:ac:c2:1a:97:82:23:b0:2c:de:7c:
58:f0:97:ac:5d:7d:ef:8b:e2:82:1a:d4:d1:7e:38:
96:22:09:61:fd:73:36:d2:8c:3e:09:6b:e4:f1:f5:
d2:c7:2a:ed:4a:eb:f8:97:36:17:b3:e9:46:c9:f7:
6b:83:74:91:ff:cb:ed:5a:ad:d5:60:5c:2c:77:2a:
b2:62:23:0c:1c:af:4a:12:6e:30:54:7b:1b:96:f1:
30:40:23:39:f3:b6:09:a4:67:b1:65:d3:ef:05:32:
a7:a2:b8:7a:74:cc:18:9e:bc:e3:e4:89:f3:e5:36:
a0:c3:a9:e4:a1:27:49:08:a4:b2:3d:ae:76:11:69:
a0:32:c9:2e:43:94:4e:93:76:eb:5c:60:89:f2:a4:
c8:ec:1e:8d:fb:91:46:61:dc:c7:4b:5b:08:83:ef:
5c:e7:a1:2b:61:4c:87:58:2c:a0:1b:2f:34:21:82:
e7:ab:f0:62:d2:2c:52:7a:36:f8:c5:39:34:d4:27:
64:ae:47:83:d0:2d:a3:7c:0c:f2:5d:86:09:d1:3b:
3a:fd:0c:f6:93:a3:a3:c4:36:89:02:d0:41:bb:23:
14:03:9c:2e:05:54:bf:89:75:68:44:36:19:0a:2e:
14:b5
Exponent: lu IÕ8~0xlx)

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Exponent: lu IÕ8~0xlx)
*s:
*sX509v3 Basic Constraints: critical
*sCA:TRUE
*sX509v3 Key Usage: critical
*sCertificate Sign, CRL Sign
*sNetscape Cert Type:
*sSSL CA, S/MIME CA, Object Signing CA
*sNetscape CA Revocation Url:
*s
*sX509v3 Subject Key Identifier:
*s
*sX509v3 Authority Key Identifier:
*skeyid:D6:D5:03:E1:B4:F0:0D:82:E9:AB:F0:4C:B2:FC:84:1B:82:18:8A:76
*sDirName:/CN=OS Level_0 CA
*sserial:01
*sAuthority Information Access:
*sCA Issuers - URI:http://s1.l47qa.com/l1/ca.crt
*sX509v3 CRL Distribution Points:
*sURI:http://s1.l47qa.com/l1crl-v2.crl
*sX509v3 Certificate Policies:
*sPolicy: 1.1.1.1.1
*sCPS:
*sUser Notice:
*sExplicit Text:
*sX509v3 Issuer Alternative Name:
*semail:root@s1.l47qa.com, URI:http://sq.l47qa.com
*sX509v3 Subject Alternative Name:
*s
Signature Algorithm: sha1WithRSAEncryption
37:41:63:20:35:83:95:29:16:b1:ff:f4:7c:63:14:05:a2:f5:
ef:df:6d:10:0c:26:4d:ed:60:15:b4:18:da:be:eb:e9:8a:15:
82:f4:32:26:62:57:77:38:24:9a:f8:63:09:af:6c:7f:af:1c:
de:ff:a4:50:7c:5e:38:b3:64:ff:03:a0:81:4d:3a:75:dd:e0:
95:13:83:96:a1:dc:04:1f:4b:0b:59:b9:ec:8f:ea:f8:f4:fe:
a0:58:92:14:3b:82:ec:3d:03:ab:2a:0c:96:74:b4:f0:4b:27:
88:80:ee:9a:47:42:d5:c4:c8:ae:99:eb:c6:9e:65:66:30:13:
e1:34:71:e0:b9:21:8b:4c:f4:7d:2f:08:4c:91:c3:ea:45:0e:
25:cd:b1:b8:2f:a9:bd:53:82:da:de:48:49:36:d1:e5:0e:35:
18:8a:59:7a:f3:21:c6:48:91:6b:17:70:b2:68:8a:b6:ae:15:
68:7b:33:cd:cd:cd:de:71:a7:76:35:e5:cd:58:01:ae:44:ff:
bc:50:7b:83:0b:8d:a2:83:1a:92:b1:b3:80:d8:e8:25:41:cb:
78:c4:65:7f:af:de:f4:b6:47:e9:e8:11:56:0a:bd:73:71:cb:
39:5b:70:a4:e3:77:3a:f3:44:f0:85:ba:e7:d1:65:dc:19:62:
d5:44:11:27
Certificate:
Dat
Version: lu (0xlx)
Serial Number: 1 (0x00000001)
Signature Algorithm: sha1WithRSAEncryption
Issuer: CN=OS Level_0 CA
Validity
Not Before: Feb 10 01:30:07 2006 GMT
Not After : Feb 10 01:30:07 2007 GMT
Subject: CN=OS Level_1 CA

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y
g
yp
RSA Public Key: (2048 bit)
Modulus (2048 bit):
00:a2:a9:48:46:79:dd:98:6b:9f:e9:77:b0:c7:eb:
37:ea:0a:7b:71:0d:5e:02:e6:d4:f7:1e:f2:9b:4f:
2d:f4:17:98:52:bc:13:5c:3b:83:84:f1:58:65:5b:
db:73:1b:38:96:c9:11:11:ca:6e:92:3c:80:9b:25:
3d:5a:78:15:93:00:a9:b8:82:9e:35:d3:13:1e:55:
9f:4f:87:03:d6:63:df:41:bd:51:85:5d:ef:b3:aa:
08:d9:80:43:9d:40:05:ae:10:f4:a1:0d:2c:32:b0:
d8:c5:50:59:65:01:a8:87:79:6e:f8:bf:6d:2a:90:
a0:06:f4:72:2a:26:6a:84:53:5a:0f:92:6e:07:1f:
d0:d6:6b:f9:2b:a3:3f:bb:e3:fe:bc:90:8d:fc:db:
6f:73:1b:41:40:78:b9:a3:8f:65:57:e9:11:74:a3:
55:3d:3b:c3:8e:fb:10:b2:03:0c:bc:cc:e4:d3:04:
9c:39:eb:b7:34:1b:a4:47:f4:88:2a:a2:23:61:d0:
f0:28:fe:ce:f5:b8:8f:a0:f0:de:1b:44:95:40:91:
55:c7:ee:14:45:b5:c7:48:28:8e:c0:4a:00:c1:23:
ac:9f:4e:00:b3:57:79:e6:12:d6:d7:e1:66:a2:62:
de:7f:13:b4:1f:17:1e:5a:22:ec:32:87:1a:87:a7:
73:cf
Exponent: lu IÕ8~0xlx)
*s:
*sX509v3 Basic Constraints: critical
*sCA:TRUE
*sX509v3 Key Usage: critical
*sCertificate Sign, CRL Sign
*sNetscape Cert Type:
*sSSL CA, S/MIME CA, Object Signing CA
*sNetscape CA Revocation Url:
*s
*sX509v3 Subject Key Identifier:
*s
*sX509v3 Authority Key Identifier:
*skeyid:9F:FF:BF:23:B9:CC:BE:3B:BA:97:94:60:01:60:FB:F9:EF:E8:54:A3
*sDirName:/CN=OS Level_0 CA
*sserial:00
*sAuthority Information Access:
*sCA Issuers - URI:http://s1.l47qa.com/ca.crt
*sX509v3 CRL Distribution Points:
*sURI:http://s1.l47qa.com/crl-v2.crl
*sX509v3 Certificate Policies:
*sPolicy: 1.1.1.1.1
*sCPS:
*sUser Notice:
*sExplicit Text:
*sX509v3 Issuer Alternative Name:
*semail:root@s1.l47qa.com, URI:http://s1.l47qa.com
*sX509v3 Subject Alternative Name:
*s
Signature Algorithm: sha1WithRSAEncryption
95:2a:1a:b2:c0:07:54:ed:72:25:88:70:8e:b0:af:89:43:7b:

a9:fe:19:9d:0e:c1:b0:f9:73:ec:66:db:38:30:39:91:92:71:

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d3:c2:64:4d:24:41:5a:2c:17:3d:34:27:8b:0c:25:60:6b:3a:
86:f6:54:fc:8d:31:08:3b:dd:4c:cb:46:fb:47:a3:e4:23:3d:
82:33:84:d2:fb:81:05:61:95:09:98:a4:25:f0:55:eb:80:0c:
32:69:48:cf:41:7c:36:2d:d7:c0:02:79:a1:7b:4d:28:4c:84:
64:68:3c:8a:af:28:5f:f6:78:1e:31:d4:5a:2c:60:20:12:99:
5c:e3:df:59:01:79:7c:20:c8:f5:ab:75:e6:ab:db:de:2a:e7:
be:4d:a1:9d:d5:5a:7c:9a:22:14:ca:7b:31:9d:48:d8:62:3a:
ab:97:15:6b:4f:13:3e:35:c0:fb:82:57:20:e7:08:03:33:28:
19:20:16:24:28:98:d4:f7:cf:0b:4b:0c:7e:6a:88:54:b0:06:
2e:df:b3:6e:ea:8e:4a:a0:60:78:73:40:a7:75:80:ef:96:cb:
f1:03:96:83:cf:1a:38:a7:33:82:d5:2e:e7:51:93:06:59:b5:
95:16:a4:34:d4:63:e7:9f:6e:7b:aa:30:13:ed:3e:47:a1:b9:
f8:56:d6:11

Figure 14 shows the certificate hierarchy.

FIGURE 14

Certificate Hierarchy

The root CA certificate "OS level 0 CA" was not included in the chain because it was already trusted
by the client, and the client accepted the chain, as shown in Figure 14.

Common Mistakes
The following mistakes often occur when dealing with server certificates and CA chains:

• Symptom: The certificate chain is not properly uploaded.

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Solution: To verify that the certificate chain is properly uploaded on ServerIronADX, connect to
the BP console and enter the show ssl certificate  command. Make sure that all of
the intermediate CA certificates are included.

• Symptom: The wrong format was specified when uploading the certificate. For example, the
certificate was obtained in DER format but uploaded in PEM format.
Solution: Check the certificate from the BP console to make sure that it is readable.

• Symptom: The certificate is chained but "enable-certificate-chaining" command is not enabled
under ssl profile
Solution: If chained certificates are used then "enable-certificate-chaining" command is
required under ssl profile definition. The chaining is disabled by default to improve system
performance.

• Symptom: Certificate is signed by Verisign, but it is shown as expired when the client tries to
connect to the ServerIron. This usually occurs if the client browser has an expired copy of the
intermediate CA certificate.
Solution: Refer to the following URL from Verisign Web site. Download the current copy of
intermediate CA certificate and either replace the expired copy on client browser with the new
copy or append the intermediate CA certificate to the server certificate on the ServerIron.
http://knowledge.verisign.com/search/solution.jsp?id=vs5781
Perform steps 1 and 2 in the following sections to append intermediate CA certificates to
server certificates.

Step 1: Import Server Certificate and Intermediate CA Certificates
To chain SSL certificates, follow these steps:
1. Import the server certificate using the following command:
scp -1 /home/rr/server.crt rr@30.30.1.1:sslcert:chain2cert:pem

2. Import the intermediate CA certificate using the following command:
scp -1 /home/rr/inter.crt rr@30.30.1.1:sslcert:chain2cert:pem

NOTE
In this example, server.crt is issued by intermediate CA. The inter.crt is the intermediate CA
certificate.

NOTE

The order is important. The server certificate should be imported before the intermediate CA
certificate.

NOTE

The same file name should be used (chain2cert in this example) when importing both the server and
intermediate CA certificate.

Step 2: Enable Certificate Chain
By default, for CA signed certificates, the ServerIronADX does not send the entire certificate chain
when presenting the certificate to the client.

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To enable the ServerIronADX to send the entire certificate chain configure the
enable-certificate-chaining command within an SSL profile as described in “Enabling a certificate
chain” on page 169.

Support for SSL renegotiation
Some SSL application clients use renegotiation as a way within SSL protocols to change cipher
specifications and redo the handshake. It has been found however that unsecure renegotiation is
susceptible to Man-in-the-Middle attack.
Although ServerIron ADX does not support renegotiation and is therefor not susceptible to these
attacks, it doesn’t handle renegotiation requests from the client properly in some cases which
causes some web browsers to report a security flaw with ServerIron ADX which is a false alarm.
With this feature enabled as shown, a ServerIron ADX responds to renegotiation requests which
stops the browser from sending false alarms.
ServerIronADX(config)# server respond-with-renegotiation-info

Syntax: {no} ssl server respond-with-renegotiation-info
With this command enabled, a ServerIron ADX will look for renegotitation-related heaters in SSL
packets and respond accordingly.
Where this command is not enabled, a ServerIron ADX ignores all renegotiation-related headers.

NOTE
While a ServerIron ADX with this command enabled will respond to renegotiation requests,
ServerIron ADX does not currently support renegotiation.

Basic SSL profile configuration
All SSL configuration parameters are configured in the configuration level under the specific SSL
profile. An SSL profile is created using the ssl profile command at the General configuration level
as shown.
ServerIronADX(config)# ssl profile profile1
ServerIronADX(config-ssl-profile-profile1)#

Syntax: ssl profile 
The  variable is an ASCII string that specifies the name of the SSL profile being
defined.
At a minimum the following parameters need to be configured for an SSL profile:

• The RSA key-pair for the SSL connection
• The cipher suite for the SSL connection
• The digital certificate for the SSL connection (specified or self-signed)

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Specifying a keypair file
Each SSL profile must be associated with an RSA key-pair file that was previously defined using the
genrsa command. The following example uses the keypair-file command to associate the key pair
file named "rsakey" with the "profile1" SSL profile.
ServerIronADX(config)# ssl profile profile1
ServerIronADX(config-ssl-profile-profile1)# keypair-file rsakey

Syntax: keypair-file 
The  variable is an ASCII string a keypair file that was generated using the
genrsa command.

Specifying a cipher suite
By specifying cipher suites under an SSL profile, you can control the security strength of the SSL
handshakes. The ServerIronADX can accept a new SSL handshake from the client only if the list of
cipher suites presented by the client includes a cipher suite configured under the SSL profile.
The following example specifies that all cipher suites are configured under the "profile1" SSL
profile.
ServerIronADX(config)# ssl profile profile1
ServerIronADX(config-ssl-profile-profile1)# cipher-suite all-cipher-profiles

Syntax: cipher-suite rsa-export-with-des40-cbc-sha | rsa-export-with-rc4-40-md5 |
rsa-with-3des-ede-cbc-sha | rsa-with-aes-128-sha | rsa-with-aes-256-sha |
rsa-with-des-cbc-sha | rsa-with-rc4-128-md5 | rsa-with-rc4-128-sha | all-cipher-suites
Use the rsa-export-with-des40-cbc-sha parameter to specify that cipher suite.
Use the rsa-export-with-rc4-40-md5 parameter to specify that cipher suite.
Use the rsa-with-3des-ede-cbc-sha parameter to specify that cipher suite.
Use the rsa-with-aes-128-sha parameter to specify that cipher suite.
Use the rsa-with-aes-256-sha parameter to specify that cipher suite.
Use the rsa-with-des-cbc-sha parameter to specify that cipher suite.
Use the rsa-with-rc4-128-md5 parameter to specify that cipher suite.
Use the rsa-with-rc4-128-sha parameter to specify that cipher suite.
Use the all-cipher-suites parameter to specify all cipher suites including the other parameters used
in this command.

NOTE

The export cipher suites work only if the asymmetric key pair strength is less than or equal to 512
bits. This is consistent with the export rules. If the RSA key pair strength is greater than 512 bits,
then SSL handshake requests that contain export cipher suites do not work.

Configuring Multiple Cipher Suites
Among the cipher suite options, is one that specifies all cipher suites. You can also specify more
than one cipher inside an SSL profile without specifying all options. This is shown in the following
example.

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To configure this feature, use commands such as the following:
ServerIronADX(config)#ssl profile sp1
ServerIronADX(config-ssl-profile-sp1)# cipher-suite rsa-with-aes-128-sha
ServerIronADX(config-ssl-profile-sp1)# cipher-suite rsa-with-rc4-128-md5
ServerIronADX(config-ssl-profile-sp1)# cipher-suite rsa-with-rc4-128-sha

Specifying a certificate file
Each SSL profile must be associated with a certificate file that was either imported or self
generated as described in “Chained certificates” on page 139. The following example uses the
certificate-file command to associate the certificate file named "certfile1" with the "profile1" SSL
profile.
ServerIronADX(config)# ssl profile profile1
ServerIronADX(config-ssl-profile-profile1)# certificate-file certfile1

Syntax: certificate-file 
The  variable is an ASCII string that specifies a certificate file that either self
generated on the ServerIronADX using the ssl gencert command or imported into the
ServerIronADX as described in “Chained certificates” on page 139.

Advanced SSL profile configuration
This section describes the following advanced SSL configuration options:

•
•
•
•
•

Client authentication
Enabling Session caching
Enabling SSLv2
Enabling close notify
Disabling Certificate verification

All SSL configuration parameters are configured in the configuration level under the specific SSL
profile. An SSL profile is created using the ssl profile command at the General configuration level
as shown in “Basic SSL profile configuration”.

Configuring client authentication
The following features can be configured for certificate management:

•
•
•
•

166

Enabling certificate verification
Configuring a CA certificate file
Creating a certificate revocation list
Allowing self signed certificates

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Enabling certificate verification
The ServerIronADX can be optionally configured to enforce client certificate verification. When
client certificate verification is configured, the ServerIronADX requires all clients to present their
signed certificates. The certificates are compared against trusted CAs and a connection is allowed
or denied.
You can enable client certificate verification on a per-ssl-handshake or per-connection basis in one
of two modes:

• Request mode
• Require mode
In request mode, a client-certificate is requested. The connection is allowed if the client presents a
valid certificate, or if a certificate is not presented at all. The connection is denied if a client
presents an invalid, revoked, or expired certificate.
In require mode, a client-certificate is always required.
Client-authentication can be used in the following four combinations:

•
•
•
•

Per-connection request
Per-connection require
Per-ssl-handshake request
Per-ssl-handshake require

Syntax: verify-client-cert  

• per-ssl-handshake - Requests a client certificate for every new SSL handshake.
• per-connection - Requests a client certificate for every new SSL connection.
The difference between the two modes is apparent if SSL session caching is enabled. When this is
the case, multiple SSL connections share the same SSL session, without performing a full SSL
handshake for each connection.

Client certificate verification in SSL Proxy Mode
SSL Proxy mode has two traffic segments: from the client to the ServerIronADX and from the
ServerIronADX to the server.
In the first segment, the ServerIronADX acts a server to a browser-based client. In the second
segment, ServerIronADX acts as a client to the real server.
In some cases the real server is configured so that only clients with valid certificates can connect to
it. Because the ServerIronADX is also a client, it must have a valid client certificate to connect to
the real server. A client certificate can be obtained from a CA, and uploaded to the ServerIronADX.
Once uploaded, the client certificate should be configured in the server ssl profile using the
following commands:

• keypair-file - To configure client-certificate key
• certificate file - To configure client-certificate
Client certificate verification in the second traffic segment (from the ServerIronADX to the server)
can also be enabled. In this configuration, the real server allows a connection only from the
ServerIronADX. No other device is allowed. To connect to the real server, the ServerIronADX must
present a client certificate issued by a CA and trusted by the server.
To successfully complete this process, the ServerIronADX requires the following items:

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• A certificate issued by a CA that is trusted by the server
• A key-pair for the certificate
The certificate and the key can be obtained from the CA in either PKCS or PEM format. For
client-authentication to work, these items must be uploaded to the ServerIronADX and then added
to the server profile.
For example, if you use si_client_cert.pem as the certificate and si_client_key.pem as the key for
the client certificate, you can add them to the profile using the following commands:
ServerIronADX(config)# ssl profile serverProfile
ServerIronADX(config-ssl-profile-serverProfile)# keypair-file si_client_key.pem
ServerIronADX(config-ssl-profile-serverProfile)# certificate-file
si_client_cert.pem

Configuring a CA certificate file
If you have enabled client certificate verification, you must configure a CA certificate under the SSL
profile. CA certificates are used by the ServerIronADX to verify the validity of certificates presented
by incoming clients.
CA certificates are typically imported from outside using SCP, in PEM format and are stored in the
flash memory, just like regular certificate files.
Up to four CA certificate files can be specified under each SSL profile. Each CA certificate file can
contain multiple CA certificates (although to keep configurations simple, We recommend that
different CA certificates be stored in different files).
You can include up to 32 DN names for all root or intermediate CA certificates. This allows clients to
select appropriate CA and intermediate CA certificates for communication with a ServerIronADX.
Unlike regular certificates, there is no need to load the corresponding key pair into the profile
before configuring a CA certificate since the CA certificate belongs to the Certificate Signing
Authority, meaning the key pair is private and not be publicly available. The following example
specifies the CA certificate file named "certfile1" for SSL profile "profile1".
ServerIronADX(config)# ssl profile profile1
ServerIronADX(config-ssl-profile-profile1)# ca-cert-file certfile1

Syntax: ca-cert-file 
The  variable specifies the name of the certificate file where a CA
certificate is stored.

NOTE
You can optionally disable certificate verification as described in “Disabling certificate verification”
on page 171.

Creating a certificate revocation list
Certificate revocation lists contain the list of certificates that have been revoked by a CA. A
certificate can be revoked by a CA for many reasons. A common reason is that the key pair that
corresponds to the issued certificate has been compromised.
Certificate revocation lists are typically maintained on the CA Web site and may be downloaded
using HTTP. The format of the list is usually DER or PEM.

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The ServerIronADX supports configuration of up to ten CRL records. For each CRL record, the size is
up to 255K.
Syntax: ssl crl-record   der | pem 
The  variable specifies a name for the CRL entry. The value of this entry is an ASCII
string.
The  variable specifies the location where the CRL is located. This value can be either an IP
address or a domain name.
The pem parameter directs the CRL to be downloaded in the PEM format.
The der parameter directs the CRL to be downloaded in the DER format.
The  variable specifies the number of hours to wait before updating the
CRL.

NOTE

Limiting the maximum number of connections from all client-ip’s is supported only via the max-conn
default  command. The max-conn 0.0.0.0/0  command is no longer supported.

NOTE
To avoid “man-in-the-middle” attacks, where the CRL may be compromised while on the network,
CRLs are digitally signed by the issuing CAs. For this reason, it is essential that the certificate of the
CA that issues the CRL is present on the ServerIronADX when a client certificate is being checked
for revocation.

Allowing Self Signed Certificates
By default, the a ServerIronADX does not accept certificates that have been issued by a CA that is
not trusted. A ServerIronADX only accepts certificates which have been signed by a CA that is
configured under the SSL profile. For testing purposes, customers may want to use self-signed
certificates (generated using the Open SSL utilities or by the ServerIron cert gen utility) on the SSL
client.
The following example configures a ServerIronADX to accept self signed certificates.
ServerIronADX(config)# ssl profile profile1
ServerIronADX(config-ssl-profile-profile1)#allow-self-signed-cert

Syntax: [no] allow-self-signed-cert

Enabling a certificate chain
By default, for CA signed certificates, the ServerIronADX does not send the entire certificate chain
when presenting the certificate to the client.
To enable the ServerIronADX to send the entire certificate chain (including the root CA certificate
and any intermediate CA certificates), enter the following commands in the SSL profile
configuration mode:
ServerIronADX(config)#ssl profile profile1

Syntax: ssl profile 
ServerIronADX(config-ssl-profile-ssl-profile1)# enable-certificate-chaining

Syntax: enable-certificate-chaining

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NOTE

All intermediate CA certificates need to be uploaded to the ServerIronADX.

Configuring certificate chain depth
You can configure certificate chain depth up to which certificate verification can be done by a
ServerIronADX. The default value is 4 and it can be configured up to 10 as shown in the following.
ServerIronADX(config)#ssl profile profile1
ServerIronADX(config-ssl-profile-ssl-profile1)# verify-cert-depth 10

Syntax: [no] verify-cert-depth 
The  variable specifies the maximum certificate chain depth verified. The accepted
values are 4 - 10. The default value is 4.

Enabling session caching
Session caching or session reuse is a mode of operation in SSL where multiple SSL connections
can share the same SSL session. A complete SSL handshake is done only for the first connection.
All subsequent connections use the parameters negotiated in the first connection, for as long as
the SSL session is cached.
By default, session caching is turned off on the ServerIronADX.
The following example enables session caching for the SSL client in the SSL profile "profile1".
ServerIronADX(config)# ssl profile profile1
ServerIronADX(config-ssl-profile-profile1)# session-cache on

Syntax: [no] session-cache { on| off }
The on parameter enables session caching for the SSL client.
The off parameter disables session caching. This is the default state.

NOTE

Please note that SSL session caching will not work with the server source-port-hash command
because that command will redirect traffic (from the same client IP) with different TCP source ports
to different BPs.

Configuring session cache size
You can specify the maximum number of session-cache entries per profile, as shown in the
following example:
ServerIronADX(config-ssl-profile-ssl1)# session-cache max-entries 512

Syntax: [no] session-cache max-entries 
The  can have a value between 512 and 8192.
The default value is 1024.

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Configuring a session cache timeout
By default, SSL sessions are held in the cache for 30 seconds. You can change the time period a
session is in cache, as shown in the following.
ServerIronADX(config)# ssl profile profile1
ServerIronADX(config-ssl-profile-profile1)# session-cache-timeout

Syntax: [no] session-cache-timeout 
The  variable can be set to a value between 20 and 86400 seconds. The
default value is 30 seconds.

Enabling SSL Version 2
By default, the ServerIronADX supports SSL version 3. You can enable SSL version 2 as shown in
the following example.
To do this, enter the following command under the SSL profile:
ServerIronADX(config)# ssl profile profile1
ServerIronADX(config-ssl-profile-profile1)# enable-ssl-v2

Syntax: [no] enable-ssl-v2
SSLv2 is disabled by default.

Enabling close notify
You can configure a ServerIronADX to send an alert before closing an SSL session as shown in the
following.
ServerIronADX(config)# ssl profile profile1
ServerIronADX(config-ssl-profile-profile1)# enable-close-notify

Syntax: [no] enable-close-notify
When this command is configured, the ServerIronADX will send an alert before closing an SSL
session. By default, a ServerIronADX does not send a close notify alert before closing an SSL
session.

Disabling certificate verification
You can configure an ServerIron ADX to disable certificate verification as shown in the following:
ServerIronADX(config)# ssl profile profile1
ServerIronADX(config-ssl-profile-profile1)# disable-certificate-checking

Syntax: [no] disable-certificate-checking
This command only applies to SSL proxy mode. When a ServerIron ADX is in SSL proxy mode, it acts
as a client for the backend server.
By default, if the server sends a certificate with the wrong information, the ServerIron ADX will
reject it. If this command is configured, the ServerIron ADX will accept an invalid certificate.

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Enabling a ServerIron ADX SSL to respond with renegotiation headers
Some SSL application clients use renegotiation as a way within SSL protocols to change cipher
specifications and redo the handshake. It has been reported that unsecure renegotiation is
susceptible to Man-in-the-Middle attack. ServerIron ADX does not support renegotiation. This
means that ServerIron ADX is not susceptible to these attacks.
A problem occurs however where some Web browsers using OpenSSL send renegotiation related
headers and expect a response. If a ServerIron ADX does not respond with an appropriate header
for renegotiation, these web browers miss-intreprete the ServerIron ADX to be vulnerable to
renegotiation attacks.
With release 12.4.00, an option has been added to configure a ServerIron ADX to respond with
renegotiation headers that tell the browers that the ServerIron ADX handles the renegotaiton
message correctly and stops them from sending the false message that the ServerIron ADX is
vulnerable to renegotiation attacks.
Configuring this command as shown in the following does not enable renegotiation on the
ServerIron ADX but prevents the problem with false reporting.
ServerIronADX# server ssl respond-with-renegotiation-info

Syntax: [no] server ssl respond-with-renegotiation-info

NOTE
The ServerIron ADX will still not support renegotiation. If the client attempts to renegotiate, the
ServerIron ADX will immediately terminate the handshake with the "NO_Renegotiation" handshake
message. However since the ServerIron ADX is now responding to the renegotiation headers,
OpenSSL clients that did not have any problem with ServerIron ADX NOT supporting renegotiation
might now be mislead to believe that ServerIron ADX has started supporting renegotiation. If this
occurs you may need to turn off this feature using the no option.

Configuring Real and Virtual Servers for SSL Termination and Proxy
Mode
When configuring a ServerIron ADX for SSL Termination and Proxy mode, the Real and Virtual
Servers need to be configured to support these features. the following sections describe the
procedures and commands required. For a description of SSL Termination Mode, see “SSL
Termination Mode” on page 137. For a description of SSL Proxy Mode, see “SSL Proxy Mode” on
page 138. For a detailed example of how to configure the examples shown in those sections, see
“Configuration Examples for SSL Termination and Proxy Modes” on page 176.

NOTE

SSL Termination and Proxy mode can be configured for setups where an IPv4 real server is bound
to an IPv4 virtual server or where an IPv6 real server is bound to an IPv6 virtual server. They are not
supported for setups that use IPv4 and IPv6 together in the same configuration.

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Configuring Real and Virtual Servers for SSL Termination Mode
Real and Virtual Server configuration is described in detail in the Brocade ServerIron ADX Server
Load Balancing Guide. When configuring a Real or Virtual Server for SSL Termination Mode, you
need to do the following:

•
•
•
•

Configure a Real Server with an HTTP port
Configure a Virtual Server with an SSL port
Enable SSL termination and specify an SSL profile on the SSL port of the Virtual Server
Bind SSL on the Virtual Server to an HTTP port on a Real Server

For IPv4 Real Server to IPv4 Virtual Server
In the example below an IPv4 Real Server and a IPv4 Virtual Server are configured for SSL
Termination mode with the following details:

• An HTTP port is defined on the Real Server: "rs1"
• An SSL port is defined on the Virtual Server: "vip1".
• SSL Termination is enabled and the SSL profile "myprofile" is specified on the Virtual Server:
"vip1".

• A bind is configured between SSL on Virtual Server: "vip1" and HTTP on Real Server: "rs1".
ServerIronADX(config)# server real rs1 10.1.1.1
ServerIronADX(config-rs-rs1)# port http
ServerIronADX(config-rs-rs1)# exit
ServerIronADX(config)# server virtual-name-or-ip vip1
ServerIronADX(config-vs-vip1)# port ssl
ServerIronADX(config-vs-vip1)# port ssl ssl-terminate myprofile
ServerIronADX(config-vs-vip1)# bind ssl rs1 http

For IPv6Real Server to IPv6 Virtual Server
In the example below an IPv6 Real Server and a IPv6 Virtual Server are configured for SSL
Termination mode with the following details:

• An HTTP port is defined on the Real Server: "rs2"
• An SSL port is defined on the Virtual Server: "vip2".
• SSL Termination is enabled and the SSL profile "ipv6_profile" is specified on the Virtual Server:
"vip2".

• A bind is configured between SSL on Virtual Server: "vip2" and HTTP on Real Server: "rs2".
ServerIronADX(config)# server real rs2 2000::1
ServerIronADX(config-rs-rs2)# port http
ServerIronADX(config-rs-rs2)# exit
ServerIronADX(config)# server virtual-name-or-ip vip2
ServerIronADX(config-vs-vip2)# port ssl
ServerIronADX(config-vs-vip2)# port ssl ssl-terminate ipv6_profile
ServerIronADX(config-vs-vip2)# bind ssl rs2 http

Syntax: [no] port ssl ssl-terminate 
The  variable specifies the name of the SSL profile that you want to bind to the
SSL port, termination mode configuration.

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Configuring Real and Virtual Servers for SSL Proxy Mode
Real and Virtual Server configuration is described in detail in the ServerIron ADX Server Load
Balancing Guide. When configuring a Real or Virtual Server for SSL Proxy Mode, you need to do the
following:

• Configure a Real Server with an SSL port
• Configure a Virtual Server with an SSL port
• Enable SSL Proxy and specify an SSL client profile and an SSL server profile on the SSL port of
the Virtual Server

• Bind SSL on the Virtual Server to an SSL port on a Real Server
For IPv4 Real Server to IPv4 Virtual Server
In the example below an IPv4 Real Server and an IPv4 Virtual Server are configured for SSL Proxy
mode with the following details:

• An SSL port is defined on the Real Server: "rs3"
• An SSL port is defined on the Virtual Server: "vip3".
• SSL Proxy is configured and the SSL client profile "IPv4clientprofile" and SSL server profile
"IPv4serverprofile" are specified on the Virtual Server: "vip3".

• A bind is configured between SSL on Virtual Server: "vip3" and SSL on the Real Server: "rs3".
ServerIronADX(config)# server real rs3 10.1.1.1
ServerIronADX(config-rs-rs3)# port ssl
ServerIronADX(config-rs-rs3)# exit
ServerIronADX(config)# server virtual-name-or-ip vip3
ServerIronADX(config-vs-vip3)# port ssl
ServerIronADX(config-vs-vip3)# port ssl ssl-proxy IPv4clientprofile
IPv4serverprofile
ServerIronADX(config-vs-vip3)# bind ssl rs3 ssl

For IPv6 Real Server to IPv6 Virtual Server
In the example below an IPv6 Real Server and an IPv6 Virtual Server are configured for SSL Proxy
mode with the following details:

• An SSL port is defined on the Real Server: "rs4"
• An SSL port is defined on the Virtual Server: "vip4".
• SSL Proxy is configured and the SSL client profile "IPv6clientprofile" and SSL server profile
"IPv6serverprofile" are specified on the Virtual Server: "vip4".

• A bind is configured between SSL on Virtual Server: "vip4" and SSL on the Real Server: "rs4".
ServerIronADX(config)# server real rs4 2000::2
ServerIronADX(config-rs-rs4)# port ssl
ServerIronADX(config-rs-rs4)# exit
ServerIronADX(config)# server virtual-name-or-ip vip4
ServerIronADX(config-vs-vip4)# port ssl
ServerIronADX(config-vs-vip4)# port ssl ssl-proxy IPv6clientprofile
IPv6serverprofile
ServerIronADX(config-vs-vip4)# bind ssl rs4 ssl

Syntax: [no] port ssl ssl-proxy  

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The  and  variables specify the name of the SSL profiles
that you want to bind to the SSL port, proxy mode configuration. The first profile is used for the
client to ServerIron ADX side and the second profile is used for the ServerIron ADX to the Real
Server side.

NOTE

The ServerIron ADX SSL proxy mode does not support session reuse that takes place on the
ServerIron ADX to the Real Server side.

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Configuration Examples for SSL Termination and Proxy Modes
This section describes the procedures required to perform the configurations described in “SSL
Termination Mode” on page 137 and “SSL Proxy Mode” on page 138. As shown in the examples
there, SSL Termination mode provides for an SSL connection between clients to the ServerIron
ADX. When configuring SSL Proxy Mode a configuration is created between the ServerIron ADX and
the server. In this case, the ServerIron ADX is configured as a client to the server.

Configuring SSL Termination Mode
In this mode, for enabling VRRPE for VIP address, it is necessary to use a different source-nat-ip for
ssl traffic.
For performing this function, use the following syntax:
Syntax: server source-nat-ip    port-range 
To configure SSL in the termination mode, perform the following tasks in sequence:
1. Generate or obtain an RSA key pair and copy it to the ServerIron ADX
2. Obtain a digital certificate and copy it to the ServerIron ADX
3. Create an SSL profile as described in “Allowing Self Signed Certificates” on page 169
4. Within the SSL profile specify a keypair file as described in “Specifying a keypair file” on
page 165.
5. Within the SSL profile specify a digital certificate file as described in “Specifying a certificate
file” on page 166.
6. Within the SSL profile select a Cipher Suite as described in “Specifying a cipher suite” on
page 165. This is optional.
7.

Configure Real and Virtual Servers as described in “Configuring Real and Virtual Servers for
SSL Termination Mode” on page 173

Example

Generate an RSA key pair
ServerIronADX# ssl genrsa rsakey-file 1024 mypassword

Generate a Self-signed Digital Certificate
ServerIronADX# ssl gencert certkey rsakey-file signkey rsakey-file mypassword
mycert
You are about to be asked to enter information that will be incorporated into
your certificate request. What you are about to enter is what is called a
Distinguished Name or a DN.
Country name (2 letter code) [US] US
State or province (full name) [California] California
Locality name (city) [city]San Jose
Organization name (Company name) [Brocade] Brocade
Organizational unit name (department) [Web administration] Web Administration
Common name (your domain name) [www.brocade.com] www.brocade.com
Email address [webadmin@brocade.com] webadmin@brocade.com
transfer_ssl_object_buf_to_bp : The object buffer length is 492
transfer_ssl_object_buf_to_bp: The message length is 622

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Create SSL profile with required settings
ServerIronADX(config)# ssl profile myprofile
ServerIronADX(config-ssl-profile-myprofile)#
ServerIronADX(config-ssl-profile-myprofile)#
ServerIronADX(config-ssl-profile-myprofile)#
ServerIronADX(config-ssl-profile-myprofile)#

keypair-file rsakey-file
certificate-file mycert
cipher-suite all
exit

Define HTTP ports on real servers
ServerIronADX(config)# server
ServerIronADX(config-rs-rs1)#
ServerIronADX(config-rs-rs1)#
ServerIronADX(config)# server
ServerIronADX(config-rs-rs2)#
ServerIronADX(config-rs-rs2)#

real
port
exit
real
port
exit

rs1 10.1.1.1
http
rs2 10.1.1.2
http

Within virtual server: Define SSL port, specify server profile and enable SSL terminate
ServerIronADX(config)# server virtual-name-or-ip vip1 10.1.1.7
ServerIronADX(config-vs-vip1)# port ssl
ServerIronADX(config-vs-vip1)# port ssl ssl-terminate myprofile

Bind SSL in virtual server to real server HTTP ports
ServerIronADX(config-vs-vip1)# bind ssl rs1 http rs2 http

Configuring SSL Proxy Mode
The ServerIron ADX acts as a client to the real server. The real server presents a certificate, but the
certificate needs to be verified by the ServerIron ADX. Because the ServerIron ADX needs the CA
certificate from the issuing authority to verify the certificate from the real server, the CA certificate
must be uploaded to the ServerIron ADX before it can be used.
To configure SSL in proxy mode, perform the following tasks in sequence:
1. Upload the CA certificate to the ServerIron ADX as described in “Transferring a Keypair File and
a Certificate File” on page 149.

NOTE

If the server is using a self-signed certificate, the allow-self-signed certificate command must
be configured within the profile.
2. Create a Client Side SSL Profile.
3. Associate an RSA key pair and certificate with the Client Side SSL Profile.
4. Within the Client Side SSL profile select a Cipher Suite as described in “Specifying a cipher
suite” on page 165. This is optional.
5. Create a Server Side SSL Profile
6. In the Server Side profile specify the name of the certificate to be associated with the SSL
Server Side profile.
7.

Configure Real and Virtual Servers as described in “Configuring Real and Virtual Servers for
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Example

Create Client Side SSL profile with required settings
ServerIronADX(config)# ssl profile clientprofile
ServerIronADX(config-ssl-profile-clientprofile)#
ServerIronADX(config-ssl-profile-clientprofile)#
ServerIronADX(config-ssl-profile-clientprofile)#
ServerIronADX(config-ssl-profile-clientprofile)#

keypair-file rsakey-file
certificate-file mycert
cipher-suite all
exit

Create server side SSL profile with required settings
ServerIronADX(config)# ssl profile serverprofile
ServerIronADX(config-ssl-profile-serverprofile)# ca-cert-file ca.cert
ServerIronADX(config-ssl-profile-clientprofile)# cipher-suite all

Define SSL ports on real servers
ServerIronADX(config)# server real rs1 10.1.1.1
ServerIronADX(config-rs-rs1)# port ssl

Within virtual server: Define SSL port, specify server profile and enable SSL proxy
ServerIronADX(config)# server virtual-name-or-ip vip3 10.1.1.3
ServerIronADX(config-vs-vip3)# port ssl
ServerIronADX(config-vs-vip3)# port ssl ssl-proxy clientprofile serverprofile

Bind SSL in virtual server to real server SSL ports
ServerIronADX(config-vs-vip3)# bind ssl rs1 ssl

TCP configuration issues with SSL Terminate and SSL Proxy
When SSL terminate or SSL proxy are enabled, the ServerIron ADX uses TCP full stack. In such
case, the Nagle Algorithm and delayed ACK mechanism are ON by default. There are instances
where both of these features should be disabled.
For example, a customer may be experiencing slow response time because the ServerIron ADX is
sending one packet at a time, and waiting for an ACK from the server before sending the next
packet. The server is sending ACKs with a delay of 200 ms, causing a delay of 200 ms between
every successive packet. This results in extremely poor performance. Packet traces taken from the
client and server sides explain this situation in detail, as shown in the following figures.
Figure 15 shows the client ptrace information. Figure 16 shows the server ptrace information.

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FIGURE 15

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Client Capture

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FIGURE 16

Server Capture

In these examples, the HTTP GET requests are intentionally broken down into multiple parts. In real
life, you may not see GET requests divided over multiple packets.
These trace results indicate that there is degradation of performance when the ServerIronADX is
configured for SSL terminate. According to the client trace, packets 1- 10 are all handshake
messages and packets 11,13,15,17,19,21,23 are separate records, each having a small part of
the GET request, which immediately receives an ACK.
The problem in this case is on the server side. The Microsoft 2003 server has delayed ACK ON
enabled, and the delayed ACK timer is set for 200 ms. Since the Nagle Algorithm is ON by default,
the ServerIronADX will not send the next packet as long as there is unacknowledged data. As
shown in the server side trace, the first data that is sent to the server is the partial GET request.
The complete GET request has 6 more parts. Packet number 4 is the partial GET, for which you see
an ACK in packet 5.
Packet 4, length 71, (frame-size) is not a full-sized packet, so the server waits for more data
packets, since it has advertised a greater window size. Because the Nagle Algorithm is enabled, the
ServerIronADX does not send any more data and the server only sends an ACK after 200 ms
(packet #5). The ServerIronADX waits to receive this ACK, and then sends the subsequent data
packet. This process continues, and all seven packets are delayed by 200 ms resulting in total
delay of 1.4 seconds, which results in the slow response time.

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Resolution
There two possible approaches to this problem.

• Turn OFF delayed ACK on the server. To see how to modify or turn off delayed ACK on Windows
2003 servers, go to the following location:
http://support.microsoft.com/default.aspx?scid=kb;en-us;823764

NOTE

This method might not be the most satisfactory, as it involves changing the registry on the
servers.

• Turn OFF Nagle Algorithm on the ServerIron. Bind the TCP-profile to the port under virtual
server.

The TCP Nagle Algorithm
The Nagle Algorithm was developed to address the TCP small packet problem. This problem is
typically experienced when an application generates several small bytes of data at a time. As an
example, one byte of user data could mean 41 bytes of packet, with 40 bytes of overhead. This
situation is often referred to as the “send-side silly window” syndrome.
The Nagle Algorithm instructs the sender to buffer the data if any unacknowledged data is
outstanding. Any data to be sent subsequently is held until the outstanding data is acknowledged
or until there is a full packet's worth of data to send. Small amounts of data are collected by TCP
and sent in a single segment.
Sometimes the Nagle Algorithm needs to be turned OFF. For example, in X-Window system, the
small size messages (such as mouse movements) need to be delivered without any delay to
provide real-time feedback for an interactive user.

Delayed TCP ACK
A host that is receiving a stream of TCP data segments can increase efficiency by sending fewer
ACKs (acknowledgements) per data segment received using a TCP delayed ACK mechanism. A TCP
should implement delayed ACKs, but no ACK should be excessively delayed.Specifically, the delay
MUST be less than 0.5 seconds, and in a stream of full-sized segments there should be an ACK for
at least every second segment.
The following example configures a TCP profile that turns off the delayed ACK, the Nagle Algorithm,
and disables all outgoing data packets except the last one from a tcp-transmit queue. The TCP
profile is then applied to Virtual Servers

Creating a TCP Profile
You can disable the following TCP features within a TCP profile: Nagle’s algorithm, the delayed ACK
algorithm, and all outgoing data packets except the last one from a tcp-transmit queue. The
following example creates a TCP profile named "nagleoff" within the General Configuration mode.
ServerIronADX(config)# tcp profile nagleoff
ServerIronADX(config-tcp-profile-nagleoff)# nagle off
ServerIronADX(config-tcp-profile-nagleoff)# delayed-ack off
ServerIronADX(config-tcp-profile-nagleoff)# push-bit off

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Disabling Nagle’s Algorithm
You can disable Nagle’s algorithm within a TCP profile as shown in the following example.
ServerIronADX(config)# tcp profile tcpprofile1
ServerIronADX(config-tcp-profile-tcpprofile1)# nagle off

Syntax: [no] nagle off
Disabling the delayed ACK algorithm
You can disable the delayed ACK algorithm within a TCP profile as shown in the following example.
ServerIronADX(config)# tcp profile tcpprofile1
ServerIronADX(config-tcp-profile-tcpprofile1)# delayed-ack off

Syntax: [no] delayed-ack off
Disabling PUSH flag in outgoing data packets from the TCP transmit queue
You can disable setting PUSH flag in all outgoing data packets except when emptying the TCP
transmit queue, as shown in the following example.
ServerIronADX(config)# tcp profile tcpprofile1
ServerIronADX(config-tcp-profile-tcpprofile1)# push-bit off

Syntax: [no] push-bit off
Modifying TCP receive queue size
You can modify the TCP receive queue size, as shown in the following example. The default value is
28000 bytes.
ServerIronADX(config)# tcp profile tcpprofile1
ServerIronADX(config-tcp-profile-tcpprofile1)# rxbuf-size 

Syntax: [no] rxbuf-size 
Modifying TCP transmit queue size
You can modify the TCP transmit queue size, as shown in the following example. The default value
is 20000 bytes.
ServerIronADX(config)# tcp profile tcpprofile1
ServerIronADX(config-tcp-profile-tcpprofile1)# txbuf-size 

Syntax: [no] txbuf-size 

Applying the TCP profile to VIP for SSL terminate
In a SSL Terminate configuration, the TCP profile can be applied either to the port ssl ssl-terminate
command in the Virtual Server configuration, or to the SSL profile that is being applied to the
Virtual Server.
In the following example, the TCP profile is applied to the port ssl ssl-terminate command in the
Virtual Server configuration
ServerIronADX(config)# server virtual-name-or-ip vip1
ServerIronADX(config-vs-vip1)# port ssl ssl-terminate sslprofile myprofile

Syntax: [no] port ssl ssl-terminate  [tcp-proxy]

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You can also apply the TCP profile to the SSL profile. In the following example, the TCP profile
"nagleoff" is applied to the SSL profile: "myprofile" and then "myprofile" is applied to the port ssl
ssl-terminate command in
ServerIronADX(config)# ssl profile myprofile
ServerIronADX(config-ssl-profile-myprofile)# tcp-profile nagleoff
ServerIronADX(config-ssl-profile-myprofile)# exit
ServerIronADX(config)# server virtual-name-or-ip vip1
ServerIronADX(config-vs-vip1)# port ssl ssl-terminate sslprofile myprofile

Applying the TCP profile to VIP for SSL Proxy
In a SSL Proxy configuration, the TCP profile must be applied to the client and server SSL profiles
that are being applied to the Virtual Server.
ServerIronADX(config)# server virtual-name-or-ip vip1
ServerIronADX(config-vs-vip1)# port ssl ssl-proxy clientprofile serverprofile
ServerIronADX(config)# ssl profile clientprofile
ServerIronADX(config-ssl-profile-clientprofile)# tcp-profile nagleoff
ServerIronADX(config-ssl-profile-clientprofil)# exit
ServerIronADX(config)# ssl profile serverprofile
ServerIronADX(config-ssl-profile-serverprofile)# tcp-profile nagleoff
ServerIronADX(config-ssl-profile-serverprofile)# exit
ServerIronADX(config)# server virtual-name-or-ip vip1
ServerIronADX(config-vs-vip1)# port ssl ssl-proxy clientprofile serverprofile

Inserting a certificate in an HTTP header
The ServerIron ADX optionally inserts the client certificate as the HTTP header, to allow the real
server to access the client certificate information.

• When configuring this feature, you need to do the following in addition to a normal SSL
Terminate configuration:

• Create a CSW policy to enable client certificate insertion
• Bind CSW and the CSW policy to the SSL port on the Virtual Server
• Define the Client Insertion mode and prefix within a CSW policy (optional)
Configuring a CSW Policy to enable client certificate insertion
A CSW Policy needs to be created that enables client certificate insertion. It can be configured as
either a default command within a CSW policy (as shown in the following example) or as an action
in response to a match in a CSW rule.
ServerIronADX(config)# csw-policy cswp1
ServerIronADX(config-csw-cswp1)# default rewrite request-insert client-cert

Syntax: [no] default rewrite request-insert client-cert
Syntax: [no] match  rewrite request-insert client-cert
Bind CSW and CSW policy to the Real Server
ServerIronADX(config)# server virtual-name-or-ip vip1
ServerIronADX(config-vs-vip1)# port ssl csw-policy "cswp1"
ServerIronADX(config-vs-vip1)# port ssl csw

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Define client Iinsertion mode and prefix
The client certificate insertion mode and prefix can be optionally configured within a CSW policy as
described in the following. To configure the client insertion mode, use the default rewrite
request-insert command as shown.
ServerIronADX(config)# csw-policy cswp1
ServerIronADX(config-csw-cswp1)# default rewrite request-insert client-cert

Syntax: [no] default rewrite request-insert client-cert [entire-chain | leaf-cert | wellknown-fields]
Selecting the entire-chain parameter directs the ServerIron ADX to insert the entire chain including
the leaf certificate in BASE64 encoded form. This is the default mode.
Selecting the leaf-cert parameter directs the ServerIron ADX to insert only the leaf certificate in
BASE64 encoded form, even though the certificate chain is present.
If the wellknown-fields parameter is selected the important information of the client certificate is
retrieved and inserted as the HTTP headers, in plain text. If this mode is chosen, the following
headers are inserted: "Client-Cert-Version", "Client-Cert-Serial", "Client-Cert-Start", "Client-Cert-End",
"Client-Cert-Subject", "Client-Cert-Subject-CN", "Client-Cert-SubjectAlt-CN", "Client-Cert-Issuer" and
"Client-Cert-Issuer-CN".
You can add a prefix to the default HTTP names using the default rewrite request-insert
certheader-prefix command. In the following example, the prefix "SSL" added to the HTTP header
"Client-Cert" would become "SSL-Client-Cert".
ServerIronADX(config)# csw-policy cswp1
ServerIronADX(config-csw-cswp1)# default rewrite request-insert client-cert
certheader-prefix "SSL"

Syntax: [no] default rewrite request-insert client-cert certheader-prefix 
The value specified by the  variable is added to the default HTTP name.
The HTTP header names are shown in Table 18.

TABLE 18

HTTP Header Names and Descriptions

Header Names

Descriptions

Client-Cert

The entire client certificate chain or the leaf certificate.

Client-Cert-Version

Version of the client certificate.

Client-Cert-Serial

Serial number of the client certificate.

Client-Cert-Start

Date certificate not valid before.

Client-Cert-End

Date certificate not valid after.

Client-Cert-Subject

Subject's distinguished name.

Client-Cert-Subject-CN

Subject's common name.

Client-Cert-Subject-Alt-CN

Subject's alternative name.

Client-Cert-Issuer

Issuer's distinguished name.

Client-Cert-Issuer-CN

Issuer's common name.

Other protocols supported for SSL
SSL acceleration support is provided to other popular protocols such as LDAPS, POP3S, and IMAPS.
Configuration of SSL acceleration support for these protocols is shown the following example.

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ServerIronADX(config)# server real rs1
ServerIronADX(config-rs-rs1)# port pop3
ServerIronADX(config-rs-rs1)# port imap4
ServerIronADX(config-rs-rs1)# port ldap
ServerIronADX(config-rs-rs1)# exit
ServerIronADX(config)#
ServerIronADX(config)# server real rs2
ServerIronADX(config-rs-rs2)# port pop3
ServerIronADX(config-rs-rs2)# port imap4
ServerIronADX(config-rs-rs2)# port ldap
ServerIronADX(config-rs-rs2)# exit
ServerIronADX(config)#
ServerIronADX(config)# server virtual-name-or-ip vip1
ServerIronADX(config-vs-vip1)# port pop3s
ServerIronADX(config-vs-vip1)# port pop3s ssl-terminate sslprof
ServerIronADX(config-vs-vip1)# bind pop3s rs1 pop3 rs2 pop3
ServerIronADX(config-vs-vip1)# exit
ServerIronADX(config)#
ServerIronADX(config)# server virtual-name-or-ip vip1
ServerIronADX(config-vs-vip1)# port imaps
ServerIronADX(config-vs-vip1)# port imaps ssl-terminate sslprof
ServerIronADX(config-vs-vip1)# bind imaps rs1 imap4 rs2 imap4
ServerIronADX(config-vs-vip1)#
ServerIronADX(config-vs-vip1)# port ldaps
ServerIronADX(config-vs-vip1)# port ldaps ssl-terminate sslprof
ServerIronADX(config-vs-vip1)# bind ldaps rs1 ldap rs2 ldap
ServerIronADX(config-vs-vip1)# exit
ServerIronADX(config)#

Configuring the system max values
This section describes how to configure the following system max values on a ServerIron ADX:

•
•
•
•

SSLv2 connection rate
Memory limit for SSL hardware buffers
Number of SSL profiles
Maximum number of SSL concurrent connections

NOTE

Setting all of the system-max values to their maximum value is not advisable as it consumes a large
amount of system memory. Please set these values only if necessary.

Configuring SSLv2 connection rate
You can configure the maximum connection rate for SSLv2, as shown in the following example.
ServerIronADX(config)# ssl-v2-rate 

Syntax: ssl-v2-rate 
The  variable sets the maximum connections for SSLv2 allowed per second.
Valid range: 16 to 256
Default: 100

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NOTE

Please note that the connection count for the SSLv2 rate includes both client-side (Terminate /
Proxy) and server-side (Proxy) connections.

Configuring memory limit for SSL hardware buffers
You can configure the maximum memory allocated for the buffers accessed by the SSL hardware,
as shown in the following example.
ServerIronADX(config)# ssl mem-size 64

The  variable sets the maximum memory for SSL hardware buffers in MB (1048576 bytes).
Valid range: 64MB to 256MB
Default: 96MB

Configuring number of ssl profiles
You can configure the maximum number of SSL profiles, as shown in the following example:
ServerIronADX(config)#system-max ssl-max-profiles 64

Syntax: [no] system-max ssl-max-profiles 
The  variable sets the maximum number of SSL profiles.
Valid range: 64 to 2048 (ADX10000,4000), 64 to 1024 (ADX1000)
Default: 1024 (ADX10000,4000), 256 (ADX1000)

Configuring the maximum number of SSL concurrent connections
Use the system-max ssl-concurrent-conn command to set the maximum number of SSL concurrent
connections, as shown in the following.
ServerIronADX# system-max ssl-concurrent-conn 1024

Syntax: [no] system-max ssl-concurrent-conn 
The  variable sets the maximum number of SSL concurrent
connections.
Valid range: 1024 to 16384(ADX4000,10000), 512 to 16384 (ADX1000).
Default: 8192

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SSL debug and troubleshooting commands
This section describes SSL debug and troubleshooting commands.

Diagnostics
You can run diagnostic tests on the SSL hardware devices to verify proper functionality. Please note
that the diagnostic tests should not be run while SSL traffic is being processed. Also, the system
should be reloaded after running the diagnostic test-suite. The diagnostic test-suite can be initiated
from the MP or from individual BPs.
To run diagnostics from the MP,
ssl diag ServerIronADX# ssl diag  
 and  refer to the BP that the diagnostic test-suite is run from
SSL chip 1: All diag tests PASSED
SSL chip 2: All diag tests PASSED
…
SSL: Diags PASSED

The above command runs all diagnostic tests on all SSL hardware modules, and logs whether the
tests passed or failed in brief.
If additional information is needed, the diagnostic tests can be run from any BP wherein detailed
information is logged on the BP console.
To run diagnostics from the BP,
SSL operations submitted to the hardware can be run in 2 modes - Blocking and Non-blocking.
Blocking mode means that the CPU is polling for the result after submitting the operation to the
hardware, and Non-blocking mode means that the CPU receives a callback once the operation has
completed. The default mode is Blocking. To change the mode,
ServerIronADX1/1# ssl bp-diag mode [ blocking | non-blocking]

There are multiple SSL devices in the system. The default module is the first module (0). To select a
specific module,
ServerIronADX1/1# ssl bp-diag module 

SSL operations submitted to the hardware can be in 2 modes - Direct and Scatter-Gather. Direct
mode means that the data for any input/output variable is in one location, and Scatter-Gather
mode means that the data for any input/output variable could come from multiple non-contiguous
blocks. The default mode is Direct. To enable scatter-gather,
ServerIronADX1/1# ssl bp-diag scatter-gather [ enable | disable ]
ServerIronADX1/1# ssl bp-diag
all
All diagnostic tests
crypto-3des
Crypto 3DES Test
crypto-aes
Crypto AES Test
crypto-hmac
Crypto HMAC Test
crypto-mod-ex
Crypto Mod-Ex Test
crypto-rc4
Crypto RC4 Test
key-mem
Key Memory Test
load-ucode
Load Microcode Test
random-num
Random Number Generator Test
read-write-regs
Read Write Registers Test

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soft-reset

Soft Reset Test

Detailed information is logged on the BP console when these tests are run.

Displaying SSL information
The following SSL Statistics information is available from the BP console within the rconsole mode:

•
•
•
•
•
•
•
•
•
•
•

Connection proxy debug counters
Connection proxy statistics
Authentication statistics
Locally stored SSL certificates
SSL connection information
CRL status record
SSl debug counters
Locally stored SSL keys
Information about specific SSL keys
Details of SSL profiles
Information about SSL record sizes

Using Rconsole
To access the display command that present this information, you must enter the BP console using
the rconsole command as shown.
ServerIronADX# rconsole 1 1

Syntax: rconsole  
The  variable specifies the number of the slot that the ASM is installed in whose BP console
you want to access.
The  variable specifies the number of the barrel processor whose BP console you want to
access.

Displaying proxy debug counters
Use the show cp debug command in the rconsole mode to display connection proxy debug counters
as shown in the following.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show cp debug
CPU high water mark reached, SYN dropped
session alloc failed
server sock error or timeout
client sock error or timeout

[
[
[
[

10]:
36]:
84]:
85]:

29991204
1607078
8
525

Syntax: show cp debug

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Displaying proxy statistics
Use the show cp statistics command in the rconsole mode to display connection proxy statistics, as
shown in the following.
ServerIronADX# rconsole 1
ServerIronADX1/1# show cp
Client-side counters:
SSL conn established
TCP conn established
rx blocked
save data (await srv con)
data tx done
data tx pending
data mv pending
closed conn
RST rcvd
conn close complete

Server-side counters:
conn established
rx blocked
data tx done
data tx pending
data mv pending
closed conn
RST rcvd
conn close complete

1
statistics
:
:
:
:
:
:
:
:
:
:

24190
0
17589
17259
13394
13394
0
19941
0
19925

SSL handshake done :
data rx :
rx unblocked :

17630
17589
13443

no tx data to send
ready to tx data
data mv done
remote closed conn
RST sent
sock error or timeout

:
:
:
:
:
:

730
13394
0
20044
4265
0

:
:
:
:
:
:
:
:

13811
13394
13430
13408
0
20034
49
18989

data rx
rx unblocked
no tx data to send
ready to tx data
data mv done
remote closed conn
RST sent
sock error or timeout

:
:
:
:
:
:
:
:

13497
13394
0
13430
0
15261
3500
1652

Syntax: show cp statistics

Displaying authentication statistics
Use the show ssl authentication-stats command in rconsole mode to display authentication
statistics about certificate verification on the ServerIron ADX. This information is relevant either in
the case of client certificate verification (on the client side), or while doing SSL proxy (on the server
side).
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show ssl authentication-stats
SSL certificate verification counters:
Success :
18384
Failure
Unknown user :
0
Signature failed
Certificate expired :
0
Certificate revoked
Cert not yet valid :
0
Cert signature failed
Issuer pubkey decode fail :
0
Self signed cert
Issuer cert not found :
0
Subject Issuer mismatch
Certificate untrusted :
0
Cert chain too long
Cert not sent by peer :
0

:
:
:
:
:
:
:

0
0
0
0
36768
0
0

CRL counters:
CRL load failed :

0

CRL signature failed :

0

CRL not found :
CRL expired :

0
0

CRL not yet valid :

0

Syntax: show ssl authentication-stats

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Displaying locally stored SSL certificates
Use the show ssl certificate command to display locally stored SSL certificates, as shown in the
following.
ServerIronADX# show ssl certificate *
ssl certificate files:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16

:
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:

cert3003.pem
cert2112.pem
cert2031.pem
cert4030.pem
cert3301.pem
cert3220.pem
cert2410.pem
cert2014.pem
cert4013.pem
cert3203.pem
cert3122.pem
cert3041.pem
cert2312.pem
cert2231.pem
cert2150.pem
cert3501.pem

Syntax: show ssl certificate  | *
The  variable specifies the name of the certificate you want information
about.
Selecting the * parameter displays a list of all locally stored certificates.

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Displaying SSL connection information
Use the show ssl con command in rconsole mode to display SSL connection information as shown
in the following.
ServerIronADX1/1# show ssl con
SOCK_ID STATE
FLAGS SSL ptr
00000000
5 00000000 00000000
00000002
5 00000000 00000000
00000003
5 00000000 00000000
00000004
5 00000000 00000000
00000005
5 00000000 00000000
00000006
5 00000000 00000000
00000007
5 00000000 00000000
00000008
5 00000000 00000000
00000009
5 00000000 00000000
0000000a
5 00000000 00000000
0000000b
5 00000000 00000000
0000000c
5 00000000 00000000
0000000d
5 00000000 00000000
0000000e
5 00000000 00000000
0000000f
5 00000000 00000000
00000010
5 00000000 00000000
00000011
5 00000000 00000000
00000012
5 00000000 00000000
00000013
5 00000000 00000000
00000014
5 00000000 00000000
ServerIronADX 40002/7#

CB_FLAGS
00002000
00002000
00002000
00002000
00002000
00002000
00002000
00002000
00002000
00002000
00002000
00002000
00002000
00002000
00002000
00002000
00002000
00002000
00002000
00002000

CP_RXQ
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000

SSLRXQ
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000

ERR
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0

Syntax: show ssl con *

Displaying the status of a CRL record
Use the show ssl crl command Use the show ssl crl command in rconsole mode to display the
status of a CRL record. This command shows the configuration status of the CRL, but not the
contents.
ServerIronADX# show ssl crl verisigncrl
CRL name
: verisigncrl
IP address
: 5.1.1.5
URL
: /verisign/temp
CRL state
: Successfully Downloaded
Last downloaded : 15:30:01, Oct-31, 2005
Expiry time
: 1 hours

Syntax: show ssl crl 
The  variable specifies the name of the CRL record that you want to display status for.
This command shows the configuration status of the CRL, but not the contents.

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ServerIronADX(config)# ssl crl crl1 http://192.168.5.16/temp.crl pem 1

ServerIronADX#show ssl crl 
(on MP)
Output :
URL : /temp.crl
IP address : 192.168.5.16
CRL state : Download complete
CRL size : 2029 bytes
Expiry time : 1 hour
Next download : After 1 hour and 9 minutes
ServerIronADX3/1#show ssl crl 
3/1 #sh ssl crl crl1

(on BP)

Certificate Revocation List (CRL):
Version lu (0xlx)
Signature Algorithm: md5WithRSAEncryption
Issuer: /C=BE/O=BELNET/OU=BEGrid/CN=BEGrid
CA/emailAddress=gridca@belnet.be
Last Update: Oct 3 07:44:18 2005 GMT
Next Update: Nov 7 07:44:18 2005 GMT
Revoked Certificates:
Serial Number: 05
Revocation Date: Dec 31 23:59:59 1999 GMT
Serial Number: 08
Revocation Date: Dec 31 23:59:59 1999 GMT
Serial Number: 09
Revocation Date: Dec 31 23:59:59 1999 GMT
Serial Number: 0A
Revocation Date: Dec 31 23:59:59 1999 GMT
Serial Number: 31
Revocation Date: Dec 31 23:59:59 1999 GMT
Serial Number: 32
Revocation Date: Dec 31 23:59:59 1999 GMT
Serial Number: 33
Revocation Date: Dec 31 23:59:59 1999 GMT
Revocation Date: Dec 31 23:59:59 1999 GMT
Revocation Date: Dec 31 23:59:59 1999 GMT
Signature Algorithm: md5WithRSAEncryption
56:dd:42:ee:3f:37:52:7a:c2:9f:92:9d:8d:84:c5:9a:4a:fc:
43:38:b6:f1:9a:14:7f:d7:cb:6c:54:00:78:cb:9d:ac:4b:fd:
cc:65:fe:86:5b:97:f8:40:5d:7b:16:dd:8d:91:2a:24:76:ca:
28:e0:b1:8c:86:22:1f:94:60:67:e5:de:21:b4:77:c8:45:36:
cf:b4:b8:2c:13:46:69:30:b3:24:b7:80:48:11:2b:47:38:a2:
a2:50:8a:96:0c:e7:36:de:9b:eb:ee:df:d7:7c:33:a7:f1:b7:
cc:24:eb:67:70:13:9c:c0:61:e5:85:d4:6c:61:80:b0:3a:d3:
5f:19:cc:80:51:5d:39:19:49:b1:d9:d1:9e:ef:06:35:24:90:
5a:b1:9b:27:0d:d0:70:a0:e2:b5:cd:a6:52:b1:9b:90:a5:3e:
25:91:dd:b3:f9:e5:e0:f6:65:50:90:5f:64:ea:3c:00:e7:13:
6e:f8:3a:58:1d:1f:ac:34:2b:f9:db:50:cb:93:68:fd:1d:6a:
8f:dc:db:6e:c7:31:b8:ed:a0:5e:4c:b1:a7:65:94:40:a5:fa:
e4:8f:97:bc:c1:c0:3f:ed:05:9a:25:3b:36:f5:3e:d8:bb:12:
45:9f:28:4c:26:24:3d:33:72:08:ef:88:b2:d3:2a:d3:9b:1e:

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Displaying SSL debug counters
Use the show ssl debug command in the rconsole mode to display debug counters, as shown in the
following.
ServerIronADX1/1 #show ssl debug
Library [code]
Description [code]:
SSL [ 20]
certificate verify failed [ 137]:
SSL [ 20]
uninitialized [ 301]:

count
90219

Syntax: show ssl debug *

Displaying SSL key information
The show ssl key command allows you to display a list of all locally stored keys or obtain
information about a specified key.
The following example displays all locally stored keys.
ServerIronADX# show ssl key *
ssl key files:
1
: key-test
2
: key1
3
: keyz
4
: keyc
5
: key7

Syntax: show ssl key *

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The following example provides information about a specified key: "rsakey".
ServerIronADX# show ssl key rsakey
modulus:
00:d6:41:66:47:98:e2:56:9d:4f:7d:e2:da:88:2e:
eb:72:39:c9:3c:3a:be:65:73:01:a1:fc:38:c5:c0:
bb:18:d6:65:70:ec:d5:11:57:61:2e:72:84:d4:e1:
67:bf:87:50:50:c2:73:f3:9a:bb:41:e1:d0:d8:a0:
d5:9a:30:15:a5:0a:7d:67:53:4a:eb:19:04:a8:82:
72:75:74:3b:2f:d4:a5:19:09:6d:ac:1f:05:d5:c0:
94:e5:34:93:19:f6:a8:43:7d:1b:59:44:c8:c7:6e:
80:c2:37:d0:30:e6:66:91:ea:f3:93:88:f4:5d:29:
c4:78:39:4e:a7:34:52:9e:63
publicExponent: lu A¹8~0xlx)
privateExponent:
00:d4:a5:a2:32:cb:5d:51:23:de:a2:8d:c5:e1:45:
d8:2e:cd:85:99:be:9f:fb:a6:72:67:68:22:9c:ba:
d5:b7:28:0b:14:52:2a:82:84:9c:12:72:5c:bd:c0:
5d:ad:2d:4a:9c:6c:f2:92:43:ef:38:cb:3b:f1:d5:
67:4b:1a:10:4f:a5:24:c9:af:b2:5d:b3:59:68:b9:
0b:e9:0b:e4:25:3c:d7:62:6d:e0:c3:d6:89:9f:3c:
63:3f:f2:17:6b:e5:26:fe:26:f1:90:03:3f:3b:60:
8b:3d:8e:c2:7a:bd:6a:78:95:3c:1b:25:82:a6:55:
40:a1:6e:53:38:fe:2d:6b:e1
prime1:
00:f6:6c:9b:9b:68:e5:d6:5a:eb:2b:3e:d6:45:07:
cf:f4:ec:4a:4c:56:97:a9:76:91:b4:8c:ce:7d:02:
b4:1c:43:9b:52:30:33:ae:29:a1:e5:97:54:d6:5e:
d2:b9:23:40:d9:6c:1d:ee:21:7e:78:5e:63:44:14:
a2:1b:bd:53:53
prime2:
00:de:94:c8:08:54:42:f9:4f:f2:0b:d5:6f:71:d5:
fc:a1:63:a2:1b:39:6e:a1:33:82:49:65:4c:27:b7:
22:28:fc:82:1b:fc:cb:7a:fc:e6:ba:ad:41:e0:00:
10:5d:1f:e7:25:ab:66:27:93:07:67:94:89:5f:8d:
4b:7f:35:b6:b
33:25:03:7e:d3:dc:b0:0a:9a:b8:95:08:1f:b7:a9:
5f:aa:13:19:98:f7:4d:42:c0:a6:fa:7a:78:d3:b0:
d2:14:ee:0d:b6:d7:63:14:5c:f7:ab:da:fd:cb:1c:
6d:34:75:e7:2a:5b:63:eb:2b:b6:8b:d0:8a:76:c5:
d6:80:0a:e5
exponent2:
00:86:05:25:d0:c6:13:b1:94:6e:94:ab:86:38:0f:
f5:d6:a3:6c:47:62:34:77:c1:d1:10:2a:7b:49:6a:
9e:99:f9:38:ca:6b:53:86:11:63:48:41:ec:69:59:
37:6b:38:47:71
coefficient:
00:a0:e6:54:0d:34:13:8f:e3:fe:b4:7b:10:57:67:

Syntax: show ssl key  | *
The  variable specifies a locally stored SSL key that you want to display information
for.

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The * parameter displays a list of all locally stored SSL keys.

Displaying an SSL Profile
The show ssl profile command allows you to display the configuration of a particular SSL profile or
all configured SSL profiles. The following example displays all configured SSL profiles on a
ServerIron ADX.
ServerIronADX# show ssl profile *
SSL profile : ssl-profile-yue
Certificate file : certfile1
Key file : rsakey1
SSL cipher suite : RC4-MD5:EXP-RC4-MD5:RC4-SHA:DES-CBC-SHA:EXP-DES-CBC-SHA:DES-C
BC3-SHA:AES128-SHA:AES256-SHA:EXP1024-RC4-MD5:EXP1024-DES-CBC-SHA:EXP1024-RC4-SH
A:RC2-CBC-MD5:EXP-RC2-CBC-MD5:DES-CBC-MD5:DES-CBC3-MD5
SSL profile : 2048
Certificate file : certfile2
Key file : rsakey2
SSL cipher suite : RC4-MD5:EXP-RC4-MD5:RC4-SHA:DES-CBC-SHA:EXP-DES-CBC-SHA:DES-C
BC3-SHA:AES128-SHA:AES256-SHA:EXP1024-RC4-MD5:EXP1024-DES-CBC-SHA:EXP1024-RC4-SH
A:RC2-CBC-MD5:EXP-RC2-CBC-MD5:DES-CBC-MD5:DES-CBC3-MD5

Syntax: show ssl profile  | *
The  variable specifies an SSL profile that you want to display information for.
The * parameter displays all configured SSL profiles.

Displaying the session cache statistics for and SSL profile
Use the show ssl profile session-cache stats command to on the rconsole, as shown in the
following to display the session cache statistics for a specified SSL profile.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show ssl profile sptest session-cache stats
1024 items in the session cache
0 client connects (SSL_connect())
0 client renegotiates (SSL_connect())
0 client connects that finished
18369 server accepts (SSL_accept())
0 server renegotiates (SSL_accept())
18349 server accepts that finished
3496 session cache hits
6458 session cache misses
120 session cache timeouts
0 callback cache hits
8339 cache full overflows (ld allowed)

Syntax: show ssl profile  session-cache stats
The  variable specifies an SSL profile that you want to display session cache
statistics for.

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Displaying the certificate bound to an SSL profile
Use the show ssl profile cert command on the rconsole, as shown in the following, to display the
certificate bound to a specified profile. This is useful when checking to see if a certificate is intact
on the BPs.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show ssl profile prof1 cert
SSL profile : prof1
Certificate:
Data:
Version: 00000003 (0x00000002)
Serial Number: 00000002 (0x00000002)
Signature Algorithm: sha1WithRSAEncryption
Issuer: C=us, ST=ca, L=sj, O=brocad, OU=web, CN=www.brocade.com
Validity
Not Before: Jun 3 12:53:01 2009 GMT
Not After : Jun 3 12:53:01 2010 GMT
Subject: C=us, ST=ca, L=sj, O=brocad, OU=web, CN=www.brocade.com
Subject Public Key Info:
Public Key Algorithm: rsaEncryption
RSA Public Key: (1024 bit)
Modulus (1024 bit):
00:d9:ef:2b:51:f9:70:b3:67:f3:17:e2:10:29:f5:
4d:43:8d:38:6f:bc:64:bf:92:1d:ec:4b:53:3a:3d:
cf:f9:35:72:55:18:b5:eb:ea:46:4a:68:2d:20:de:
f0:6f:05:24:89:a5:d6:a8:67:66:fe:db:5a:3d:5f:
8d:44:31:6f:6d:cc:17:8f:7a:a1:7b:49:8a:25:29:
eb:d5:5c:a9:58:20:43:f2:57:0b:7c:09:a5:8a:ac:
bc:71:c3:6f:58:9e:41:3f:60:8d:8d:94:a4:3c:dd:
1e:53:dd:9e:21:e7:c8:1e:58:e8:d5:cf:0c:41:84:
57:e9:9f:ad:9a:e8:16:61:f1
Exponent: 00010001 (0x00010001)
Signature Algorithm: sha1WithRSAEncryption
59:0b:30:f0:06:c6:2c:b3:73:d3:40:91:5c:47:bb:d4:9c:ae:
bb:d3:61:90:8a:d4:04:ee:81:a2:57:6e:76:a3:0b:a2:1a:08:
9d:ce:d3:4a:95:ab:ef:62:36:6b:bc:ba:30:e3:4a:ce:1a:79:
fe:b3:95:d6:4c:57:2d:3d:12:a9:b6:cf:aa:7d:80:83:1d:d2:
3f:49:47:1e:d8:1f:94:47:ae:2b:f7:68:4f:51:eb:8e:30:df:
d5:27:cd:d4:41:1a:11:85:a6:d1:1c:5b:c0:1a:60:f6:52:f0:
8c:bd:d8:a0:56:cf:88:97:95:f4:30:e6:78:65:0e:ac:b7:80:
fa:23

Syntax: show ssl profile  cert
The  variable specifies name of the profile that you want to display the certificate
for.

Displaying the key that is bound to an SSL profile
Use the show ssl profile key command on the rconsole, as shown in the following, to display the key
bound to a specified profile. This is useful when checking to see if a key is intact on the BPs.
ServerIronADX# rconsole 1 1
ServerIronADX# show ssl profile test1 key
SSL profile : test1
Key file : \usb0\certstor\key7.key
Private-Key: (1024 bit)
modulus:

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6

00:ac:6e:a1:3d:3c:0a:f3:df:e2:8d:b4:5e:d6:cb:
90:e3:96:87:2d:bc:aa:41:64:22:fa:ea:c2:86:d8:
b1:bc:99:c5:c6:af:87:2d:d1:2b:89:b9:31:6f:9c:
35:03:86:9b:47:6d:82:a8:4f:88:07:dc:46:8a:87:
86:5c:cd:15:c6:3d:de:72:05:68:0b:50:b5:77:27:
9f:6c:33:a3:8b:2a:de:e6:f7:b3:f3:70:e6:b9:cc:
8d:4c:84:25:b7:2f:62:d6:76:ed:93:59:87:f7:4c:
b1:99:23:f0:9f:d9:61:d3:e1:e7:40:a0:12:6a:1d:
f5:20:b7:2e:2b:08:9e:80:c5
publicExponent: 00010001 (0x00010001)
privateExponent:
42:81:64:e5:16:4c:6f:25:51:df:2f:cb:48:73:39:
4d:de:58:02:f6:fa:7f:c0:1c:91:c4:8c:04:b0:7d:
54:ed:c6:4f:4c:92:09:c4:dc:53:01:3f:a4:f9:8d:
a4:ef:7c:e2:7e:c5:5f:1f:55:ab:1a:75:86:a6:a0:
d7:18:2e:a6:26:29:96:8c:e8:7e:38:df:da:5b:c5:
90:ca:e1:3d:a3:1b:03:a7:95:e9:59:be:18:8b:dc:
28:0a:3f:8f:a1:68:c1:07:2e:9a:8f:19:9e:e0:17:
96:eb:7e:40:57:97:f6:13:05:e2:0e:0e:06:b8:02:
a7:00:a3:ff:19:c2:42:9d
prime1:
00:db:a6:28:e7:8e:ed:26:44:12:e5:bc:d5:05:98:
d7:c2:02:f1:3c:b7:72:7e:51:7c:31:3e:9c:9a:d9:
1a:a9:93:3c:c5:a2:27:85:1f:24:89:46:6c:4c:b8:
bb:d0:ef:eb:d2:0e:0b:95:d5:47:bb:27:9a:50:f6:
00:68:62:57:6b
prime2:
00:c8:f8:09:b0:fe:87:4f:08:ab:00:f4:e7:ef:2d:
a5:85:5a:2a:25:4f:ed:49:ba:60:55:d5:72:ce:69:
fe:4b:ef:d7:c1:9a:a4:b3:42:68:aa:e7:9a:e0:d3:
ee:62:99:72:df:9c:3a:1d:59:5f:74:c4:08:fe:7d:
9a:ef:76:04:8f
exponent1:
47:3b:bd:ec:4a:d7:f2:1f:05:99:e8:01:95:cd:19:
bb:db:c4:6c:92:79:d9:29:88:03:58:70:e5:6f:1f:
4c:7b:69:ac:16:88:86:8d:b1:05:ac:07:17:62:99:
d6:8a:d8:89:c8:f0:4c:e9:5c:57:ff:e1:f5:fb:b1:
ea:28:6a:7d
exponent2:
00:a2:d4:b5:a5:7e:d5:4b:28:0e:c5:db:a9:00:95:
cf:82:d8:a7:45:4c:19:4a:9f:83:e6:87:e7:59:6f:
6f:e7:3f:11:65:80:52:ea:1b:68:8a:f0:d5:00:4d:
36:dd:14:cf:8a:76:1e:70:21:35:c2:7a:03:7f:8f:
6d:b5:8f:bd:e9
coefficient:
4c:2f:16:3e:c5:b5:c9:dc:d1:68:da:8c:e2:3d:d1:
10:48:79:80:df:a3:07:ab:84:1c:c6:86:26:f6:b2:
42:bc:3d:65:c3:0e:d3:a0:35:0c:45:75:16:30:05:
09:ca:a3:04:fc:26:49:c5:cf:78:87:97:ed:88:b8:
2b:a4:00:1a

Syntax: show ssl profile  key
The  variable specifies name of the profile that you want to display the certificate
for.

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Displaying record size information
Use the show ssl record-size command in rconsole mode to display information regarding record
size.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show ssl record-size
Decrypt
Len
Count TotalBytes
AvgBytes
< 1k
16566
1603624
96
< 2k
0
0 4294967295
< 3k
0
0 4294967295
< 4k
0
0 4294967295
< 5k
0
0 4294967295
< 6k
0
0 4294967295
< 7k
0
0 4294967295
< 8k
0
0 4294967295
< 9k
0
0 4294967295
<10k
0
0 4294967295
<11k
0
0 4294967295
<12k
0
0 4294967295
<13k
0
0 4294967295
<14k
0
0 4294967295
<15k
0
0 4294967295
<16k
0
0 4294967295
>16k
0
0 4294967295

198

Count
7413
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0

Encrypt
TotalBytes
1021277
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0

AvgBytes
137
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295

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6

Displaying socket information
The following socket information is available from the BP console within the rconsole mode.

• Socket detail in open status
• All sockets in open status
• Socket state information
To access the display command that present this information, you must enter the BP console using
the rconsole command as shown in “Using Rconsole” on page 188.

Displaying socket details in open status
Use the show socket id command in the rconsole mode to display socket detail in open status, as
shown in the following.
ServerIronADX1/1# show socket id 0
Sock
Peer
Local
0000
0.0.0.0:
0 10.10.1.100:

443

State
LISTEN

rx_q_bytes tx_q_byptes
00000000
00000000

Syntax: show socket id 
The  variable specifies the socket ID number in hexadecimal form of the socket that you
want to display details for.

Displaying all sockets in open status
Use the show socket list command in the rconsole mode to display all sockets in open status, as
shown in the following.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show sock lis
Sock
Peer
Local
State
rx_q_bytes
tx_q_byptes
0000
0.0.0.0:0
10.10.6.10:
443
LISTEN
00000000 00000000
0001
0.10.6.50:3832
10.10.6.10:
443
ESTABLISHED 00000000 00000000
0002
209.157.22.1:80 10.10.6.50:3832 SYN_SENT 00000000
00000000

Syntax: show sock list

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Displaying socket information

Displaying socket state information
Use the show socket state command in the rconsole mode to display socket state information, as
shown in the following.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show socket state
Socket Layer:
Total sockets :
65000
Max reached :
0
TCP Connection States:
Listen
SYN-sent
Close-wait
Closing
FIN-wait-2

Open sockets :
Sock mem alloc fail :

10611
0

:
:
:
:
:

2
353
1
0
0

SYN-rcvd
Established
FIN-wait-1
Last-Ack
Time-wait

:
:
:
:
:

1154
9101
0
0
0

ConnProxy (client) states:
Total count :
Wait connect :
Wait reuse :
In Use :
Wait remote close :
Wait free :

48000
0
0
3893
0
0

Used count
Wait connect complt
Wait data
Wait close
Wait close complt
RST rcvd

:
:
:
:
:
:

4916
0
1023
0
0
0

48000
0
0
3638
0
0

Used count
Wait connect complt
Wait data
Wait close
Wait close complt
RST rcvd

:
:
:
:
:
:

4539
353
547
1
0
0

ConnProxy (server) states:
Total count :
Wait connect :
Wait reuse :
In Use :
Wait remote close :
Wait free :
Reuse pool head :
0

Syntax: show socket state

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Displaying socket information

6

Displaying SSL Statistics information
The following SSL Statistics information is available from the BP console within the rconsole mode:

•
•
•
•
•

SSL Statistics alert information
Decoded status counters of SSL alerts
SSL decoded client site status counters
SSL statistical counters
SSL crypto engine status counters

To access the display command that present this information, you must enter the BP console using
the rconsole command as shown in “Using Rconsole” on page 188.

Displaying SSL Statistics alert information
Use the show ssl statistics alert command in rconsole mode to display decoded status counters of
SSL alerts as shown in the following.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show ssl statistics alert
SSL alert detail counters:
RX
TX
**************************************************************************
close_notify:
7410
0
unexpected_message:
0
2402
bad_record_mac:
0
0
decryption_failed:
0
0
record_overflow:
0
0
decompression_failure:
0
0
handshake_failure:
0
0
no_certificate:
0
0
bad_certificate:
0
0
unsupported_certificate:
0
0
certificate_revoked:
0
0
certificate_expired:
0
0
certificate_unknown:
0
0
illegal_parameter:
0
0
unknown_ca:
0
0
access_denied:
0
0
decode_error:
0
0
decrypt_error:
0
0
export_restrictionr:
0
0
protocol_version:
0
0
insufficient_security:
0
0
internal_error:
0
0
user_cancelled:
0
0
no_renegotiation:
0
0

Syntax: show ssl statistics alert

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Displaying socket information

Displaying SSL decoded client site status counters
Use the show ssl statistics client command in rconsole mode to display SSL decoded client site
status counters as shown.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show ssl statistics client
SSL Client statistics:
***********************************************************************
SSL Connect attempts:
2627919
SSL Connect failed:
0
SSL Client Hello rcvd:
746120
SSL Client Hello failed:
0
SSL Client Key Xchng rcvd:
717585 SSL Client Key Xchng failed:
0
SSL Client Finish rcvd:
717585
SSL Client Finish failed:
0
Client auth ok:
0
Client auth failed:
0
SSL Session Reuse Attempt:
0
SSL Session Reuse failed:
0
SSL Handshake complete:
717585
SSL Connect closed:
4527817
SSL Close count:
2617385
SSL Remote Close cnt:
4
SSL Reset count:
2617260
SSL Remote Reset cnt:
17
Level 1 Alerts Received:
217
Level 2 Alerts Received:
0
Level 1 Alerts Send:
108
Level 2 Alerts Send:
0
SSL Rx bytes from TCP: 206550026
SSL Rx bytes to TCP:1218384265
SSL Rx Appl Data from TCP: 74514386
SSL Tx Appl Data to TCP: 577601440
SSL Rx nonApplData from TCP: 132035640 SSL Tx nonAppl Data to TCP: 640782825
RSA Private Decrypt calls:
0
RSA Public Decrypt calls:
0
RSA Private Encrypt calls:
0
RSA Public Encrypt calls:
0
DH Compute key calls:
0
DH Generate key calls:
0
DSA Verify calls:
0
DSA Sign calls:
0
MD5 Raw hash calls:
0
SHA1 Raw hash calls:
0
3DES calls:
0
RC4 calls: 29183053
SSL MAC MD5 calls: 29183053
SSL MAC SHA1 calls:
0
TLS MAC MD5 calls:
0
TLS MAC SHA1 calls:

Syntax: show ssl statistics client

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Displaying SSL Statistics counters
Use the show ssl statistics counters command in rconsole mode to display SSL statistical counters
as shown.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show ssl statistics counter
SSL debug counters:
SSL connect attempts :
16024
SSL Handshake complete
SSL close count :
13697
SSL RemoteClose cnt
SSL reset count :
2648
SSL Remote Reset cnt
SSL tx shutdown :
11049
TCP close cnt
SSL current con :
0
SSL clientside con
SSL_Recv cnt :
9119
SSL Send cnt
Alert(2) Rx cnt :
0
Alert(2) Tx Cnt
SSL Session Attempt :
0
SSL Session Reuse failed
SSL Rx Block cnt :
37791
SSL Rx unBlock cnt
DMA_SSL_MONITOR :
32
Cavium Inst err cnt
Cavium Rd/Wr same
SSL Get Client Hello fail
FPGA ssl mon req cnt
SSL V2 rate limit drops
SSL Alert Incorrect len
SSL Record with no data
SSL HS MSGS in data xfer

:
:
:
:
:
:
:
:

0
0
0
0
0
0
0
0

SSL Random counters:
Num ssl rand buffers :
Current fetch :

SSL debug counters:
SSL Recv CB unblk error
SSL Invalid sd error
SSL read error cnt
SSL read alert error
SSL read alert error

:
:
:
:
:

:
:
:
:
:
:
:
:
:

9384
10693
0
16024
0
7413
0
0
43356

Cavium reqid not found :
Cavium pending cnt :

0
0

FPGA ssl mon done cnt
Cavium Inst overflow err
SSL Invalid record type
SSL Insufficient data in

:
:
:
:

0
0
0
0

2
0

Rand buffer size :
Rand errors :

32760
0

0
0
0
0
0

SSL Recv Pkt drop cnt :
SSL ZeroCopy Recv Err :
SSL recv err code :
SSL renegotiate start :
SSL max. frag. err :

0
0
0
0
0

Syntax: show statistics counters

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Displaying socket information

Displaying SSL crypto engine status counters
Use the show ssl statistics crypto command in rconsole mode to display SSL crypto engine status
counters as shown.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show ssl statistics crypto
SSL crypto statistics:
**************************************************************************
Csp1Handshake:
0
Csp1HandshakeStart:
0
Csp1HandshakeUpdate:
0
Csp1HandshakeFinish:
0
Csp1RsaServerFullRc4:
717850 Csp1RsaServerFullRc4Finish:
0
Csp1RsaServerVerifyRc4:
0 Csp1RsaServerVerifyRc4Finis:
0
Csp1RsaServerFull3Des:
0 Csp1RsaServerFull3DesFinish:
0
Csp1RsaServerVerify3Des:
0 Csp1RsaServerVerify3DesFini:
0
Csp1RsaServerFullAes:
0 Csp1RsaServerFullAesFinish:
0
Csp1RsaServerVerifyAes:
0 Csp1RsaServerVerifyAesFinis:
0
Csp1OtherFullRc4:
0
Csp1OtherFullRc4Finish:
0
Csp1OtherVerifyRc4:
0
Csp1OtherVerifyRc4Finish:
0
Csp1OtherFull3Des:
0
Csp1OtherFull3DesFinish:
0
Csp1OtherVerify3Des:
0
Csp1OtherVerify3DesFinish:
0
Csp1OtherFullAes:
0
Csp1OtherFullAesFinish:
0
Csp1OtherVerifyAes:
0
Csp1OtherVerifyAesFinish:
0
Csp1FinishedRc4Finish:
0
Csp1Finished3DesFinish:
0
Csp1FinishedAesFinish:
0
Csp1ResumeRc4:
0
Csp1ResumeRc4Finish:
0
Csp1Resume3Des:
0
Csp1Resume3DesFinish:
0
Csp1ResumeAes:
0
Csp1ResumeAesFinish:
0
Csp1EncryptRecordRc4: 28495624
Csp1DecryptRecordRc4:
874497
Csp1EncryptRecord3Des:
0
Csp1DecryptRecord3Des:
0 Csp1DecryptRecord3DesRecove:
0
Csp1EncryptRecordAes:
0
Csp1DecryptRecordAes:
0
Csp1DecryptRecordAesRecover:
0
Csp1RsaSsl20ServerFullRc4:
0
Csp1RsaSsl20ServerClientAut:
0
Csp1Ssl20ResumeRc4:
0
Csp1Ssl20ResumeClientAuthRc:
0 Csp1RsaSsl20ServerFull3Des:
0
Csp1RsaSsl20ServerClientAut:
0
Csp1Ssl20Resume3Des:
0
Csp1Ssl20ResumeClientAuth3D:
0
Csp1Ssl20DecryptRecordRc4:
0
Csp1Ssl20EncryptRecordRc4:
0 Csp1Ssl20DecryptRecord3Des:
0
Csp1Ssl20EncryptRecord3Des:
0
Csp1Random:
2651352
Csp1AllocKeyMem:
2
Csp1FreeKeyMem:
0
Csp1StoreKey:
2
Csp1FreeKeyMem:
0
Csp1Pkcs1v15Enc:
0
Csp1Pkcs1v15CrtEnc:
0
Csp1Pkcs1v15Dec:
0
Csp1Pkcs1v15CrtDec:
0
Csp1Pkcs1v15Dec:
0
Csp1Pkcs1v15CrtDec:
0
sdram2 to dpram:
4642933
dpram to sdram2: 15520423

Syntax: show ssl statistics crypto

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6

Displaying TCP IP information
The following TCP IP information is available from the BP console within the rconsole mode:

•
•
•
•

SSL, TCP, and IP buffer information
TCP and IP chain length statistics
SSL, TCP, and IP queues
SSL memory

To access the display command that present this information, you must enter the BP console using
the rconsole command.

Displaying SSL, TCP, and IP buffer information
Use the show tcp-ip buffers command in rconsole mode to display SSL, TCP, and IP buffer
information as shown:
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show tcp-ip buffer
Total
Free
32B
414696
146884
64B
30720
14332
128B
135168
107922
256B
69632
58092
512B
8192
6173
1KB
16384
16384
2KB
24576
24576
8KB
8192
8191
8.5KB
2048
0
14KB
192
192

Allocs
2045939
67150
846286
247866
29725
129930
77162
285319
2048
0

Frees
1778127
50762
819040
236326
27706
129930
77162
285318
0
0

MaxInUse
414696
25076
117910
54982
2639
8608
8607
6195
2048
0

SSL buffers allocated from pcie memory space ; size = 213509280 bytes

Syntax: show tcp-ip buffers

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Displaying socket information

Displaying TCP, and IP chain length statistics
Use the show tcp-ip chain-statistics command in rconsole mode to display TCP and IP chain length
statistics as shown.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show tcp-ip chain-statistics
TCP->App
Len
Count TotalBytes
AvgBytes
1
139369
35133603
252
2
0
0 4294967295
3
0
0 4294967295
4
0
0 4294967295
5
0
0 4294967295
6
0
0 4294967295
7
0
0 4294967295
8
0
0 4294967295
9
0
0 4294967295
10
0
0 4294967295
11
0
0 4294967295
12
0
0 4294967295
13
0
0 4294967295
14
0
0 4294967295
15
0
0 4294967295
16
0
0 4294967295
>16
0
0 4294967295
ServerIronADX 40002/7#

Count
19775
76315
0
17630
0
24190
0
0
0
0
0
0
0
0
0
0
0

App->TCP
TotalBytes
1265600
10870122
0
1181210
0
26078654
0
0
0
0
0
0
0
0
0
0
0

AvgBytes
64
142
4294967295
67
4294967295
1078
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295
4294967295

Syntax: show tcp-ip chain-statistics

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Displaying TCP and IP statistics
Use the show tcp-ip statistics command in rconsole mode to display TCP and IP statistics as shown
in the following.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show tcp-ip statistics
Driver Layer:
Rx cnt :
405603
Tx cnt :
445200
Tx frame data too big :
0
Tx Seg no data :
0
Tx Seg chunked :
0

Pkt mem alloc fail
No tx buffers
Tx hdrs too long
Tx seg w/ data

:
:
:
:

0
0
0
0

Fwd to upper layer :
Bad options :
Pkt truncated :

405603
0
0

Frag reassm ok :
Frag mem alloc fail :
Frag max size reached :

0
0
0

dest unreach :

2186

IP (rx) Layer:
Rx Cnt
Cksum error
Bad protocol
Bad header
Rx frag
Frag tmr alloc fail
Frag max num reached
Frag dup data rx

:
:
:
:
:
:
:
:

405603
0
0
0
0
0
0
0

IP (tx) Layer:
Rx from upper layer :

447386

TCP (rx) Layer:
Rx cnt
Rx SYN
Rx FIN
Duplicate Seg (full)
Rx seg out of wnd (full)
Cksum error (HW verified)
Bad hdr len
PAWS bad timestamp
Rx Q corrupt

:
:
:
:
:
:
:
:
:

405603
24190
35310
5161
0
0
0
0
0

Rx bad ctl flags
Rx SYN-ACK
Rx RST
Duplicate Seg (part)
Rx seg out of wnd (part)
Cksum error (SW verified)
Bad data truncation
Rx zero wnd probe
Rx unacceptable seg

:
:
:
:
:
:
:
:
:

0
19793
62
0
0
0
0
0
7

TCP (tx) Layer:
Rx from upper layer
Tx SYN
Tx FIN
Bad socket num
Bad data len
Sock already closed
Data too big
Tx busy
Tx Q corrupt

:
:
:
:
:
:
:
:
:

137910
47562
38338
0
0
0
0
0
0

Retransmitting seg
Tx SYN-ACK
Tx RST
Bad data buffer
Sock send err
Connection not estab
Tx Q full
Send wnd shrunk
Tx zero wnd probe

:
:
:
:
:
:
:
:
:

24766
25460
9194
0
0
0
0
896
0

Syntax: show tcp-ip statistics

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Show SSL memory
Use the show ssl mem command in rconsole mode to display SSL memory statistics as shown in
the following.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# show ssl mem
Total SSL Buffer Usage:
Size: 32B
64B
128B
256B
Free 23dc4 037fc 1a592 e2ec
Used 41624 04004 06a6e 2d14

512B
181d
07e3

1K
2K
8K
8.5K
14K
4000 6000 1fff 0000 00c0
0000 0000 0001 0800 0000

SSL buffers allocated from pcie memory space ; size = 213509280 bytes
SSL
SSL
SSL
SSL

buffer
buffer
buffer
buffer

dyn allocations (non-std size chunks) : 197195
dyn allocations (few std size chunks depleted) 1126328
dyn frees : 11208
malloc fail cnt : 0

Total Used DP Buffer cnt: 0x00000000
Total Used DP Buffer size: 0x00000000

Max Used DP Buffer: 0x00000000
ServerIronADX 40002/7#

Syntax: show ssl mem

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ASM SSL dump commands
The following ASM SSL dump commands can be used for troubleshooting your ServerIron ADX
system. Because these commands are performance intensive, use discretion when using them
within a production system.

asm dm ssldump
Use the asm dm ssldump command on the BP to display all transmit and receive SSL packets.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# asm dm ssldump
SSL transmit and receive packets in on now
2/1 #
1
135834ms 10.10.1.101:443->10.10.2.66:51632 Application Data
2
135835ms 10.10.1.101:443->10.10.2.189:15664 Application Data
3
135835ms 10.10.1.101:443->10.10.2.98:16578 Application Data
4
135835ms 10.10.1.101:443->10.10.2.158:10554 Application Data
5
135835ms 10.10.1.101:443->10.10.2.127:10650 Application Data
6
135836ms 10.10.1.101:443->10.10.2.194:16461 Application Data
7
135836ms 10.10.1.101:443->10.10.2.158:10601 Application Data
8
135836ms 10.10.2.33:46947->10.10.1.101:443 Application Data
9
135836ms 10.10.1.101:443->10.10.2.127:9521 Application Data
10
135836ms 10.10.1.101:443->10.10.2.33:46933 Application Data
11
135837ms 10.10.1.101:443->10.10.2.189:15664 Application Data
12
135837ms 10.10.1.101:443->10.10.2.66:51632 Application Data
13
135837ms 10.10.1.101:443->10.10.2.127:10650 Application Data
14
135838ms 10.10.1.101:443->10.10.2.98:16578 Application Data
15
135838ms 10.10.1.101:443->10.10.2.158:10554 Application Data
16
135838ms 10.10.1.101:443->10.10.2.127:9521 Application Data
17
135838ms 10.10.1.101:443->10.10.2.33:46947 Application Data
18
135838ms 10.10.1.101:443->10.10.2.194:16461 Application Data
19
135839ms 10.10.1.101:443->10.10.2.158:10601 Application Data
20
135839ms 10.10.1.101:443->10.10.2.33:46933 Application Data
21
135839ms 10.10.1.101:443->10.10.2.33:46947 Application Data
22
135840ms 10.10.1.101:443->10.10.2.33:46947 Application Data
23
135840ms 10.10.1.101:443->10.10.2.66:51632 Application Data
24
135840ms 10.10.1.101:443->10.10.2.189:15664 Application Data
25
135840ms 10.10.1.101:443->10.10.2.127:10650 Application Data
26
135841ms 10.10.1.101:443->10.10.2.98:16578 Application Data
27
135841ms 10.10.1.101:443->10.10.2.158:10554 Application Data
28
135841ms 10.10.1.101:443->10.10.2.127:9521 Application Data
29
135841ms 10.10.1.101:443->10.10.2.194:16461 Application Data
30
135841ms 10.10.1.101:443->10.10.2.33:46933 Application Data
31
135841ms 10.10.1.101:443->10.10.2.158:10601 Application Data
32
135842ms 10.10.1.101:443->10.10.2.33:46947 Application Data
33
135842ms 10.10.1.101:443->10.10.2.66:51632 Application Data
34
135843ms 10.10.1.101:443->10.10.2.189:15664 Application Data
35
135843ms 10.10.1.101:443->10.10.2.127:10650 Application Data
36
135843ms 10.10.1.101:443->10.10.2.98:16578 Application Data
37
135844ms 10.10.1.101:443->10.10.2.158:10554 Application Data
38
135844ms 10.10.1.101:443->10.10.2.194:16461 Application Data
39
135844ms 10.10.1.101:443->10.10.2.127:9521 Application Data
40
135844ms 10.10.1.101:443->10.10.2.158:10601 Application Data
41
135844ms 10.10.1.101:443->10.10.2.33:46933 Application Data
42
135845ms 10.10.1.101:443->10.10.2.33:46947 Application Data
43
135845ms 10.10.1.101:443->10.10.2.66:51632 Application Data
44
135846ms 10.10.1.101:443->10.10.2.189:15664 Application Data

Syntax: asm dm ssldump

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asm dm ssldump both
Use the asm dm ssldump both command on the BP to display both client and server SSL packets.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# asm dm ssldump both
Debug both client and server packets

Syntax: asm dm ssldump both

asm dm ssldump client
Use the asm dm ssldump client command on the BP to display client SSL packets only.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# asm dm ssldump client
Debug client packets only

Syntax: asm dm ssldump client

asm dm ssldump filter
Use the asm dm ssldump filter command on the BP to set up SSL packet filters.
Use the asm dm ssldump filter command with the following options to display SSL packets with
matching destination IP addresses.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# asm dm ssldump filter 1 dpa 

Syntax: asm dm ssldump filter  dpa 
Use the asm dm ssldump filter command with the following options to display SSL packets with
matching source IP addresses.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# asm dm ssldump filter 1 spa 1

Syntax: asm dm ssldump filter  spa 
Use the asm dm ssldump filter command with the following options to display SSL packets with
matching destination ports, use the following syntax:
ServerIronADX# rconsole 1 1
ServerIronADX1/1#asm dm ssldump filter 1 dport 80

Syntax: asm dm ssldump filter  dport 
Use the asm dm ssldump filter command with the following options to display SSL packets with
matching source ports, use the following syntax:
ServerIronADX# asm dm ssldump filter 1 sport 80

Syntax: asm dm ssldump filter  sport 

asm dm ssldump mode brief
Use the asm dm ssldump mode brief command on the BP to display SSL packet summary
information.

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asm dm ssldump mode detail
Use the asm dm ssldump mode detail command on the BP to display SSL handshake packet detail
information.

asm dm ssldump mode decrypt
Use the asm dm ssldump mode decrypt command on the BP to display SSL decrypted received
packets only.

asm dm ssldump receive
Use the asm dm ssldump receive command on the BP to display received packets only.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# asm dm ssldump receive
1
2
3
4
5

0 ms
1906ms
1935ms
1976ms
4709ms

10.10.6.50:3633->10.10.6.10:443
10.10.6.50:3633->10.10.6.10:443
10.10.6.50:3633->10.10.6.10:443
10.10.6.50:3633->10.10.6.10:443
10.10.6.50:3633->10.10.6.10:443

Handshake ClientHello
Handshake ClientKeyEx
Handshake ChangeCipherSpec
Handshake Finished
Application Data

asm dm ssldump send
Use the asm dm ssldump send command on the BP to display sent packets only.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# asm dm ssldump send
6 158955ms 10.10.6.10:443->10.10.6.50:3645
7 159064ms 10.10.6.10:443->10.10.6.50:3645
8 159105ms 10.10.6.10:443->10.10.6.50:3645
9 162812ms 10.10.6.10:443->10.10.6.50:3645
10 162837ms 10.10.6.10:443->10.10.6.50:3645
11 164822ms 10.10.6.10:443->10.10.6.50:3645

Handshake ServerHello
Handshake ServerCert
Handshake ServerHelloDone
Handshake ChangeCipherSpec
Handshake Finished
Application Data

asm dm ssldump server
asm dm ssldump server
Use the asm dm ssldump server command on the BP to display client SSL packets only.
ServerIronADX# rconsole 1 1
ServerIronADX1/1# asm dm ssldump server
Debug server packets only
ServerIronADX4/1#

Syntax: asm dm ssldump server

asm dm ssldump no-limit
Use the asm dm ssldump no-limit command to keep dumping all captured SSL packets until the
dump is stopped by entering "asm dm ssldump"

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Syntax: asm dm ssldump max 

asm dm ssldump max
Use the asm dm ssldump max  command to limit the number of packets logged on the
console.
Syntax: asm dm ssldump max 
The default value is 50.

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