Ruckus FastIron Ethernet Switch IP Multicast Configuration Guide Version 08.0.30 Fast Iron 08030 Ipmulticastguide

FastIron 08.0.30 IP Multicast Configuration Guide fastiron-08030-ipmulticastguide

2017-12-14

User Manual: Ruckus FastIron 08.0.30 IP Multicast Configuration Guide

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FastIron Ethernet Switch IP Multicast Configuration Guide

Supporting FastIron Software Release 08.0.30

CONFIGURATION GUIDE

FastIron Ethernet Switch IP Multicast

Configuration Guide

53-1003626-03

23 May 2016

Brocade, Brocade Assurance, the B-wing symbol, ClearLink, DCX, Fabric OS, HyperEdge, ICX, MLX, MyBrocade, OpenScript, VCS, VDX, Vplane, and

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Contents

Preface..........................................................................................................................................................................................................................................................................................9

Document conventions............................................................................................................................................................................................................................................. 9

Text formatting conventions.........................................................................................................................................................................................................................9

Command syntax conventions...................................................................................................................................................................................................................9

Notes, cautions, and warnings...................................................................................................................................................................................................................10

Brocade resources..................................................................................................................................................................................................................................................... 10

Contacting Brocade Technical Support..........................................................................................................................................................................................................10

Brocade customers......................................................................................................................................................................................................................................... 10

Brocade OEM customers.............................................................................................................................................................................................................................. 11

Document feedback....................................................................................................................................................................................................................................................11

About This Document........................................................................................................................................................................................................................................................ 13

Supported hardware.................................................................................................................................................................................................................................................. 13

What’s new in this document................................................................................................................................................................................................................................13

How command information is presented in this guide..........................................................................................................................................................................14

IPv4 Multicast Traffic Reduction...................................................................................................................................................................................................................................15

PIM convergence on MAC movement...........................................................................................................................................................................................................15

IGMP snooping overview....................................................................................................................................................................................................................................... 15

Queriers and non-queriers...........................................................................................................................................................................................................................16

VLAN-specific configuration.......................................................................................................................................................................................................................17

Tracking and fast leave................................................................................................................................................................................................................................... 17

Support for IGMP snooping and Layer 3 multicast routing together on the same device.....................................................................................17

Forwarding mechanism in hardware...................................................................................................................................................................................................... 17

Hardware resources for IGMP and PIM-SM snooping.............................................................................................................................................................. 18

Configuration notes and feature limitations for IGMP snooping and Layer 3 multicast routing.........................................................................18

IGMP snooping configuration..............................................................................................................................................................................................................................19

IGMP snooping mcache entries and group addresses...............................................................................................................................................................19

IGMP snooping software resource limits.......................................................................................................................................................................................... 20

Changing the maximum number of supported IGMP snooping mcache entries..................................................................................................... 20

Setting the maximum number of IGMP group addresses......................................................................................................................................................20

Enabling IGMP snooping globally on the device..........................................................................................................................................................................20

Configuring the IGMP mode...................................................................................................................................................................................................................... 21

Configuring the IGMP version................................................................................................................................................................................................................. 22

Configuring static groups to specific ports.......................................................................................................................................................................................22

Disabling IGMP snooping on a VLAN................................................................................................................................................................................................23

Modifying the age interval for group membership entries...................................................................................................................................................... 23

Modifying the query interval (active IGMP snooping mode only).......................................................................................................................................23

Modifying the maximum response time............................................................................................................................................................................................23

Configuring report control.......................................................................................................................................................................................................................... 24

Modifying the wait time before stopping traffic when receiving a leave message.................................................................................................... 24

Modifying the multicast cache age time.............................................................................................................................................................................................24

Enabling or disabling error and warning messages.....................................................................................................................................................................24

Configuring static router ports..................................................................................................................................................................................................................25

Turning off static group proxy.................................................................................................................................................................................................................. 25

Enabling IGMP V3 membership tracking and fast leave for the VLAN..........................................................................................................................25

Enabling fast leave for IGMP V2............................................................................................................................................................................................................26

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Enabling fast convergence ........................................................................................................................................................................................................................26

IGMP snooping show commands...................................................................................................................................................................................................................26

Displaying the IGMP snooping configuration.................................................................................................................................................................................26

Displaying IGMP snooping errors..........................................................................................................................................................................................................27

Displaying IGMP group information.....................................................................................................................................................................................................28

Displaying IGMP snooping mcache information..........................................................................................................................................................................29

Displaying software resource usage for VLANs...........................................................................................................................................................................30

Displaying the status of IGMP snooping traffic.............................................................................................................................................................................30

Displaying querier information...................................................................................................................................................................................................................31

Clear commands for IGMP snooping............................................................................................................................................................................................................34

Clearing the IGMP mcache........................................................................................................................................................................................................................34

Clearing the mcache on a specific VLAN..........................................................................................................................................................................................34

Clearing traffic on a specific VLAN.......................................................................................................................................................................................................34

Clearing IGMP counters on VLANs......................................................................................................................................................................................................34

Disabling the flooding of unregistered IPv4 multicast frames in an IGMP-snooping-enabled VLAN................................................................... 35

PIM SM traffic snooping overview.................................................................................................................................................................................................................. 35

Application examples of PIM SM traffic snooping.......................................................................................................................................................................35

Configuration notes and limitations for PIM SM snooping......................................................................................................................................................37

PIM SM snooping configuration.......................................................................................................................................................................................................................38

Enabling or disabling PIM SM snooping........................................................................................................................................................................................... 38

Enabling PIM SM snooping on a VLAN............................................................................................................................................................................................39

Disabling PIM SM snooping on a VLAN...........................................................................................................................................................................................39

PIM SM snooping show commands..............................................................................................................................................................................................................39

Displaying PIM SM snooping information........................................................................................................................................................................................39

Displaying PIM SM snooping information on a Layer 2 switch...........................................................................................................................................39

Displaying PIM SM snooping information for a specific group or source group pair.............................................................................................40

IPv6 Multicast Traffic Reduction.................................................................................................................................................................................................................................43

MLD snooping overview.......................................................................................................................................................................................................................................43

Support for MLD snooping and Layer 3 IPv6 multicast routing together on the same device........................................................................ 44

Hardware resources for MLD and PIMv6 SM snooping......................................................................................................................................................... 45

MLD snooping configuration notes and feature limitations....................................................................................................................................................45

MLD snooping-enabled queriers and non-queriers...................................................................................................................................................................46

MLD and VLAN configuration................................................................................................................................................................................................................. 47

MLDv1 with MLDv2........................................................................................................................................................................................................................................47

MLD snooping configuration.............................................................................................................................................................................................................................. 47

Configuring the hardware and software resource limits............................................................................................................................................................48

Configuring the global MLD mode....................................................................................................................................................................................................... 49

Modifying the age interval.......................................................................................................................................................................................................................... 49

Modifying the query interval (active MLD snooping mode only).........................................................................................................................................49

Configuring the global MLD version....................................................................................................................................................................................................50

Modifying the wait time before stopping traffic when receiving a leave message....................................................................................................50

Modifying the multicast cache aging time........................................................................................................................................................................................50

Disabling error and warning messages................................................................................................................................................................................................ 51

Configuring the MLD mode for a VLAN.............................................................................................................................................................................................51

Disabling MLD snooping for the VLAN...............................................................................................................................................................................................51

Configuring the MLD version for the VLAN......................................................................................................................................................................................51

Configuring the MLD version for individual ports........................................................................................................................................................................ 52

Configuring static groups............................................................................................................................................................................................................................52

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Disabling static group proxy......................................................................................................................................................................................................................52

Enabling MLDv2 membership tracking and fast leave for the VLAN..............................................................................................................................53

Configuring fast leave for MLDv1...........................................................................................................................................................................................................53

Displaying MLD snooping information.........................................................................................................................................................................................................54

Displaying MLD snooping error information...................................................................................................................................................................................54

Displaying MLD group information...................................................................................................................................................................................................... 54

Displaying MLD snooping mcache information............................................................................................................................................................................56

Displaying status of MLD snooping traffic........................................................................................................................................................................................57

Displaying MLD snooping information by VLAN........................................................................................................................................................................ 58

Clearing MLD snooping counters and mcache....................................................................................................................................................................................... 59

Clearing MLD counters on all VLANs.................................................................................................................................................................................................59

Clearing the mcache on all VLANs....................................................................................................................................................................................................... 59

Clearing traffic counters on a specific VLAN.................................................................................................................................................................................. 59

Disabling the flooding of unregistered IPv6 multicast frames in an MLD-snooping-enabled VLAN.....................................................................60

PIM6 SM traffic snooping overview...............................................................................................................................................................................................................60

Application examples of PIM6 SM traffic snooping................................................................................................................................................................... 60

Configuration notes and limitations for PIM6 SM snooping..................................................................................................................................................62

PIM6 SM snooping configuration....................................................................................................................................................................................................................63

Enabling or disabling PIM6 SM snooping........................................................................................................................................................................................63

Enabling PIM6 SM snooping on a VLAN.........................................................................................................................................................................................64

Disabling PIM6 SM snooping on a VLAN........................................................................................................................................................................................64

PIM6 SM snooping show commands.......................................................................................................................................................................................................... 64

Displaying PIM6 SM snooping information.....................................................................................................................................................................................64

Displaying PIM6 SM snooping for a VLAN.....................................................................................................................................................................................65

IPv4 Multicast Protocols..................................................................................................................................................................................................................................................67

Overview of IP multicasting................................................................................................................................................................................................................................. 67

Multicast terms.................................................................................................................................................................................................................................................. 67

Support for Multicast Multi-VRF......................................................................................................................................................................................................................68

system-max command changes........................................................................................................................................................................................................... 68

Show and clear command support.......................................................................................................................................................................................................68

Changing global IP multicast parameters....................................................................................................................................................................................................68

Concurrent support for multicast routing and snooping...........................................................................................................................................................69

Defining the maximum number of PIM cache entries...............................................................................................................................................................69

Defining the maximum number of IGMP group addresses...................................................................................................................................................69

Changing IGMP V1 and V2 parameters..............................................................................................................................................................................................70

Adding an interface to a multicast group........................................................................................................................................................................................................71

Multicast non-stop routing....................................................................................................................................................................................................................................72

Configuration considerations.....................................................................................................................................................................................................................72

Configuring multicast non-stop routing..............................................................................................................................................................................................73

Displaying the multicast NSR status.....................................................................................................................................................................................................73

Passive multicast route insertion ..................................................................................................................................................................................................................... 74

Configuring PMRI............................................................................................................................................................................................................................................75

Displaying hardware-drop...........................................................................................................................................................................................................................75

IP multicast boundaries.......................................................................................................................................................................................................................................... 75

Configuring multicast boundaries...........................................................................................................................................................................................................76

Displaying multicast boundaries..............................................................................................................................................................................................................76

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PIM Dense .....................................................................................................................................................................................................................................................................77

Initiating PIM multicasts on a network..................................................................................................................................................................................................77

Pruning a multicast tree................................................................................................................................................................................................................................ 77

Grafts to a multicast tree.............................................................................................................................................................................................................................80

PIM DM versions...............................................................................................................................................................................................................................................81

Configuring PIM DM ......................................................................................................................................................................................................................................81

Failover time in a multi-path topology................................................................................................................................................................................................ 84

Configuring a DR priority............................................................................................................................................................................................................................ 84

Displaying basic PIM Dense configuration information............................................................................................................................................................84

Displaying all multicast cache entries in a pruned state............................................................................................................................................................85

Displaying all multicast cache entries.................................................................................................................................................................................................. 86

PIM Sparse .................................................................................................................................................................................................................................................................. 89

PIM Sparse device types............................................................................................................................................................................................................................90

RP paths and SPT paths...............................................................................................................................................................................................................................91

Configuring PIM Sparse................................................................................................................................................................................................................................91

ACL based RP assignment....................................................................................................................................................................................................................... 95

PIM convergence on MAC movement (PIM sparse mode).............................................................................................................................................................96

IP multicast PIM neighbor filter......................................................................................................................................................................................................................... 96

Limitations............................................................................................................................................................................................................................................................97

Configuring IPv4 PIM neighbor filtering.............................................................................................................................................................................................97

PIM Passive...................................................................................................................................................................................................................................................................97

Multicast Outgoing Interface (OIF) list optimization..............................................................................................................................................................................98

Displaying system values..................................................................................................................................................................................................................................... 98

Displaying PIM resources.....................................................................................................................................................................................................................................98

Displaying PIM Sparse configuration information and statistics..................................................................................................................................................100

Displaying basic PIM Sparse configuration information.........................................................................................................................................................100

Displaying a list of multicast groups................................................................................................................................................................................................... 102

Displaying BSR information....................................................................................................................................................................................................................103

Displaying candidate RP information.................................................................................................................................................................................................104

Displaying RP-to-group mappings.....................................................................................................................................................................................................105

Displaying RP Information for a PIM Sparse group..................................................................................................................................................................105

Displaying the RP set list...........................................................................................................................................................................................................................106

Displaying multicast neighbor information......................................................................................................................................................................................107

Displaying the PIM multicast cache....................................................................................................................................................................................................108

Displaying the PIM multicast cache for DIT.....................................................................................................................................................................................110

Clearing the PIM forwarding cache................................................................................................................................................................................................................... 111

Displaying PIM traffic statistics............................................................................................................................................................................................................................111

Clearing the PIM message counters...............................................................................................................................................................................................................113

Displaying PIM RPF.................................................................................................................................................................................................................................................113

Configuring Multicast Source Discovery Protocol (MSDP)...............................................................................................................................................................113

Peer Reverse Path Forwarding (RPF) flooding.............................................................................................................................................................................. 114

Source Active caching...................................................................................................................................................................................................................................115

Configuring MSDP..........................................................................................................................................................................................................................................115

Disabling an MSDP peer.............................................................................................................................................................................................................................116

Designating the interface IP address as the RP IP address.................................................................................................................................................... 117

Filtering MSDP source-group pairs...................................................................................................................................................................................................... 117

Filtering incoming and outgoing Source-Active messages.................................................................................................................................................... 117

Filtering advertised Source-Active messages................................................................................................................................................................................ 119

Displaying MSDP information..................................................................................................................................................................................................................119

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Displaying MSDP RPF-Peer.................................................................................................................................................................................................................. 124

Displaying MSDP Peer...............................................................................................................................................................................................................................124

Displaying MSDP VRF RPF-Peer.......................................................................................................................................................................................................125

Clearing MSDP information.....................................................................................................................................................................................................................125

Configuring MSDP mesh groups ..................................................................................................................................................................................................................126

Configuring MSDP mesh group............................................................................................................................................................................................................127

MSDP Anycast RP..................................................................................................................................................................................................................................................128

Configuring MSDP Anycast RP............................................................................................................................................................................................................ 128

Example...............................................................................................................................................................................................................................................................129

PIM Anycast RP........................................................................................................................................................................................................................................................132

Configuring PIM Anycast RP..................................................................................................................................................................................................................132

Static multicast routes........................................................................................................................................................................................................................................... 134

IGMP Proxy.................................................................................................................................................................................................................................................................134

IGMP proxy configuration notes........................................................................................................................................................................................................... 135

IGMP proxy limitations................................................................................................................................................................................................................................135

Configuring IGMP Proxy............................................................................................................................................................................................................................135

Filtering groups in proxy report messages......................................................................................................................................................................................135

Displaying IGMP Proxy information....................................................................................................................................................................................................136

IGMP V3........................................................................................................................................................................................................................................................................137

Default IGMP version.................................................................................................................................................................................................................................. 138

Compatibility with IGMP V1 and V2.................................................................................................................................................................................................... 139

Globally enabling the IGMP version ...................................................................................................................................................................................................139

Enabling the IGMP version per interface setting ........................................................................................................................................................................139

Enabling the IGMP version on a physical port within a virtual routing interface .......................................................................................................139

Enabling membership tracking and fast leave..............................................................................................................................................................................140

Creating a static IGMP group..................................................................................................................................................................................................................140

Setting the query interval.............................................................................................................................................................................................................................141

Setting the group membership time.....................................................................................................................................................................................................141

Setting the maximum response time................................................................................................................................................................................................... 141

Displaying IGMPv3 information............................................................................................................................................................................................................142

Clearing the IGMP group membership table ................................................................................................................................................................................143

Displaying static IGMP groups...............................................................................................................................................................................................................143

Clearing IGMP traffic statistics ..............................................................................................................................................................................................................146

Source-specific multicast...........................................................................................................................................................................................................................147

Configuring PIM SSM group range..................................................................................................................................................................................................... 147

Configuring multiple SSM group ranges..........................................................................................................................................................................................148

IGMPv2 SSM mapping..............................................................................................................................................................................................................................149

IPv6 Multicast Protocols................................................................................................................................................................................................................................................153

IPv6 PIM Sparse ..................................................................................................................................................................................................................................................... 153

PIM Sparse router types............................................................................................................................................................................................................................ 154

RFC 3513 and RFC 4007 compliance for IPv6 multicast scope-based forwarding.............................................................................................154

IPv6 PIM-Sparse mode.............................................................................................................................................................................................................................155

Configuring IPv6 PIM-SM on a virtual routing interface.........................................................................................................................................................155

Enabling IPv6 PIM-SM for a specified VRF..................................................................................................................................................................................155

Configuring BSRs .........................................................................................................................................................................................................................................156

Enabling Source-specific Multicast..................................................................................................................................................................................................... 162

Passive Multicast Route Insertion.........................................................................................................................................................................................................163

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Clearing the IPv6 PIM forwarding cache...........................................................................................................................................................................................177

Clearing the IPv6 PIM message counters........................................................................................................................................................................................177

Updating PIM Sparse forwarding entries witha new RP configuration............................................................................................................................ 177

Clearing the IPv6 PIM traffic ...................................................................................................................................................................................................................178

Defining the maximum number of IPv6 PIM cache entries.................................................................................................................................................. 178

Configuring a static multicast route within a VRF........................................................................................................................................................................178

Configuring the route precedence by specifying the route types.......................................................................................................................................179

Configuring IPv6 PIM neighbor filtering...........................................................................................................................................................................................180

IPv6 PIM convergence on MAC movement............................................................................................................................................................................................. 181

Multicast Listener Discovery and source-specific multicast protocols.....................................................................................................................................183

Enabling MLDv2............................................................................................................................................................................................................................................ 184

Configuring MLD parameters for default and non-default VRFs......................................................................................................................................184

Configuring MLD parameters at the interface level....................................................................................................................................................................187

Displaying MLD information................................................................................................................................................................................................................... 188

Clearing IPv6 MLD traffic..........................................................................................................................................................................................................................192

Clearing the IPv6 MLD group membership table cache........................................................................................................................................................ 192

IPv6 Multicast Boundaries..................................................................................................................................................................................................................................192

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Preface

∙Document conventions.....................................................................................................................................................................................................9

∙Brocade resources.............................................................................................................................................................................................................10

∙Contacting Brocade Technical Support.................................................................................................................................................................10

∙Document feedback............................................................................................................................................................................................................11

Document conventions

The document conventions describe text formatting conventions, command syntax conventions, and important notice formats used in

Brocade technical documentation.

Text formatting conventions

Text formatting conventions such as boldface, italic, or Courier font may be used in the flow of the text to highlight specific words or

phrases.

Format Description

bold text Identifies command names

Identifies keywords and operands

Identifies the names of user-manipulated GUI elements

Identifies text to enter at the GUI

italic

text Identifies emphasis

Identifies variables

Identifies document titles

Courier font Identifies CLI output

Identifies command syntax examples

Command syntax conventions

Bold and italic text identify command syntax components. Delimiters and operators define groupings of parameters and their logical

relationships.

Convention Description

bold text Identifies command names, keywords, and command options.

italic

text Identifies a variable.

value In Fibre Channel products, a fixed value provided as input to a command option is printed in plain text, for

example, --show WWN.

[ ] Syntax components displayed within square brackets are optional.

Default responses to system prompts are enclosed in square brackets.

{ x | y | z } A choice of required parameters is enclosed in curly brackets separated by vertical bars. You must select

one of the options.

In Fibre Channel products, square brackets may be used instead for this purpose.

x | yA vertical bar separates mutually exclusive elements.

< > Nonprinting characters, for example, passwords, are enclosed in angle brackets.

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Convention Description

... Repeat the previous element, for example,

member

[

member

...].

\ Indicates a “soft” line break in command examples. If a backslash separates two lines of a command

input, enter the entire command at the prompt without the backslash.

Notes, cautions, and warnings

Notes, cautions, and warning statements may be used in this document. They are listed in the 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.

ATTENTION

An Attention statement indicates a stronger note, for example, to alert you when traffic might be interrupted or the device might

reboot.

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.

Brocade resources

Visit the Brocade website to locate related documentation for your product and additional Brocade resources.

You can download additional publications supporting your product at www.brocade.com. Select the Brocade Products tab to locate your

product, then click the Brocade product name or image to open the individual product page. The user manuals are available in the

resources module at the bottom of the page under the Documentation category.

To get up-to-the-minute information on Brocade products and resources, go to MyBrocade. You can register at no cost to obtain a user

ID and password.

Release notes are available on MyBrocade under Product Downloads.

White papers, online demonstrations, and data sheets are available through the Brocade website.

Contacting Brocade Technical Support

As a Brocade customer, you can contact Brocade Technical Support 24x7 online, by telephone, or by e-mail. Brocade OEM customers

contact their OEM/Solutions provider.

Brocade customers

For product support information and the latest information on contacting the Technical Assistance Center, go to http://

www.brocade.com/services-support/index.html.

If you have purchased Brocade product support directly from Brocade, use one of the following methods to contact the Brocade

Technical Assistance Center 24x7.

Preface

FastIron Ethernet Switch IP Multicast Configuration Guide

10 53-1003626-03

Online Telephone E-mail

Preferred method of contact for non-urgent

issues:

∙My Cases through MyBrocade

∙Software downloads and licensing

tools

∙Knowledge Base

Required for Sev 1-Critical and Sev 2-High

issues:

∙Continental US: 1-800-752-8061

∙Europe, Middle East, Africa, and Asia

Pacific: +800-AT FIBREE (+800 28

34 27 33)

∙For areas unable to access toll free

number: +1-408-333-6061

∙Toll-free numbers are available in

many countries.

support@brocade.com

Please include:

∙Problem summary

∙Serial number

∙Installation details

∙Environment description

Brocade OEM customers

If you have purchased Brocade product support from a Brocade OEM/Solution Provider, contact your OEM/Solution Provider for all of

your product support needs.

∙OEM/Solution Providers are trained and certified by Brocade to support Brocade® products.

∙Brocade provides backline support for issues that cannot be resolved by the OEM/Solution Provider.

∙Brocade Supplemental Support augments your existing OEM support contract, providing direct access to Brocade expertise.

For more information, contact Brocade or your OEM.

∙For questions regarding service levels and response times, contact your OEM/Solution Provider.

Document feedback

To send feedback and report errors in the documentation you can use the feedback form posted with the document or you can e-mail

the documentation team.

Quality is our first concern at Brocade and we have made every effort to ensure the accuracy and completeness of this document.

However, if you find an error or an omission, or you think that a topic needs further development, we want to hear from you. You can

provide feedback in two ways:

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∙By sending your feedback to documentation@brocade.com.

Provide the publication title, part number, and as much detail as possible, including the topic heading and page number if applicable, as

well as your suggestions for improvement.

Preface

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Preface

FastIron Ethernet Switch IP Multicast Configuration Guide

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About This Document

∙Supported hardware..........................................................................................................................................................................................................13

∙What’s new in this document........................................................................................................................................................................................13

∙How command information is presented in this guide................................................................................................................................. 14

Supported hardware

This guide supports the following product families from Brocade:

∙FCX Series

∙FastIron X Series (FSX 800 and FSX 1600)

∙ICX 6610 Series

∙ICX 6430 Series (ICX 6430, ICX 6430-C12)

∙ICX 6450 Series (ICX 6450, ICX 6450-C12-PD)

∙ICX 6650 Series

∙ICX 7750 Series

∙ICX 7450 Series

∙ICX 7250 Series

NOTE

The Brocade ICX 6430-C switch supports the same feature set as the Brocade ICX 6430 switch unless otherwise noted.

NOTE

The Brocade ICX 6450-C12-PD switch supports the same feature set as the Brocade ICX 6450 switch unless otherwise

noted.

What’s new in this document

This summarizes the new information added to this guide for Version 08.0.30 of the latest FastIron software release.

TABLE 1 Summary of enhancements in FastIron Release 08.0.30

Feature Description Location

Disable flooding in VLAN. Support was added for disabling the flooding of

unregistered IPv4 and IPv6 multicast frames.

See the sections “IPv4 Multicast Traffic

Reduction,” and “IPv6 Multicast Traffic

Reduction” and the

FastIron Command

Reference

PIM convergence on MAC movement Reverse Path Forwarding (RPF) check is triggered

on MAC movement for directly connected sources

and sends MAC address movement notification to

the Protocol Independent Multicast (PIM) module

which results in PIM convergence.

See the sections PIM convergence on MAC

movement on page 15 and IPv6 PIM

convergence on MAC movement on page 181.

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How command information is presented in this guide

For all new content supported in FastIron Release 08.0.20 and later, command information is documented in a standalone command

reference guide.

In an effort to provide consistent command line interface (CLI) documentation for all products, Brocade is in the process of completing a

standalone command reference for the FastIron platforms. This process involves separating command syntax and parameter

descriptions from configuration tasks. Until this process is completed, command information is presented in two ways:

∙For all new content supported in FastIron Release 08.0.20 and later, the CLI is documented in separate command pages

included in the

FastIron Command Reference

. Command pages are compiled in alphabetical order and follow a standard

format to present syntax, parameters, usage guidelines, examples, and command history.

NOTE

Many commands from previous FastIron releases are also included in the command reference.

∙Legacy content in configuration guides continues to include command syntax and parameter descriptions in the chapters

where the features are documented.

If you do not find command syntax information embedded in a configuration task, refer to the

FastIron Command Reference

About This Document

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IPv4 Multicast Traffic Reduction

∙PIM convergence on MAC movement.................................................................................................................................................................. 15

∙IGMP snooping overview...............................................................................................................................................................................................15

∙IGMP snooping configuration......................................................................................................................................................................................19

∙IGMP snooping show commands...........................................................................................................................................................................26

∙Clear commands for IGMP snooping................................................................................................................................................................... 34

∙Disabling the flooding of unregistered IPv4 multicast frames in an IGMP-snooping-enabled VLAN...........................35

∙PIM SM traffic snooping overview..........................................................................................................................................................................35

∙PIM SM snooping configuration.............................................................................................................................................................................. 38

∙PIM SM snooping show commands..................................................................................................................................................................... 39

PIM convergence on MAC movement

PIM convergence occurs when the PIM module is notified of a topology change.

The notification is triggered upon a change in port status, Reverse Path Forwarding (RPF) failure in the hardware, or by the unicast

routing module if there is a change in the Layer 3 topology. If the topology change occurs without setting off any of the two events or if

the Layer 3 topology change is not notified by the unicast routing module, PIM convergence does not take place.

If there is a change in the source traffic at the Layer 2 interface level, the RPF check fails because only loose RPF check is supported

(loose RPF check detects the change in the source traffic only at the Layer 3 interface level). A notification for a change in the source

traffic at the Layer 2 interface level can be triggered by establishing a signaling process for MAC address movement. The MAC address

movement notification triggers RPF check on MAC movement for directly connected sources. The MAC address movement notification

can be triggered by configuring the ip multicast-routing rpf-check mac-movement command. The MAC address movement notification

triggers a notification to the PIM module which results in convergence. PIM convergence is supported in both PIM Sparse and PIM

Dense modes.

PIM convergence on MAC movement is supported on the Brocade ICX 6610, FCX, Brocade ICX 6450 (when part of family stacking),

Brocade ICX 7750, and Brocade ICX 7450.

NOTE

PIM convergence on MAC movement is applicable only in a topology where the multicast source port and PIM routers are in

the same Layer 2 domain.

IGMP snooping overview

When a device processes a multicast packet, by default, it broadcasts the packets to all ports except the incoming port of a VLAN.

Packets are flooded by hardware without going to the CPU. This behavior causes some clients to receive unwanted traffic.

IGMP snooping provides multicast containment by forwarding traffic to only the ports that have IGMP receivers for a specific multicast

group (destination address). A device maintains the IGMP group membership information by processing the IGMP reports and leave

messages, so traffic can be forwarded to ports receiving IGMP reports.

An IPv4 multicast address is a destination address in the range of 224.0.0.0 to 239.255.255.255. Addresses of 224.0.0.X are

reserved. Because packets destined for these addresses may require VLAN flooding, devices do not snoop in the reserved range. Data

packets destined to addresses in the reserved range are flooded to the entire VLAN by hardware, and mirrored to the CPU. Multicast

data packets destined for the non-reserved range of addresses are snooped. A client must send IGMP reports in order to receive traffic.

An IGMP device's responsibility is to broadcast general queries periodically, and to send group queries when receiving a leave message,

to confirm that none of the clients on the port still want specific traffic before removing the traffic from the port. IGMP V2 lets clients

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specify what group (destination address) will receive the traffic but not to specify the source of the traffic. IGMP V3 is for source-specific

multicast traffic, adding the capability for clients to INCLUDE or EXCLUDE specific traffic sources. An IGMP V3 device port state could

be INCLUDE or EXCLUDE, and there are different types of group records for client reports.

The interfaces respond to general or group queries by sending a membership report that contains one or more of the following records

associated with a specific group:

∙Current-state record that indicates from which sources the interface wants to receive and not receive traffic. This record

contains the source address of interfaces and whether or not traffic will be included (IS_IN) or not excluded (IS_EX) from this

source.

∙Filter-mode-change record. If the interface state changes from IS_IN to IS_EX, a TO_EX record is included in the membership

report. Likewise, if the interface state changes from IS_EX to IS_IN, a TO_IN record appears in the membership report.

∙An IGMP V2 leave report is equivalent to a TO_IN (empty) record in IGMP V3. This record means that no traffic from this

group will be received regardless of the source.

∙An IGMP V2 group report is equivalent to an IS_EX (empty) record in IGMP V3. This record means that all traffic from this

group will be received regardless of source.

∙Source-list-change record. If the interface wants to add or remove traffic sources from its membership report, the report can

contain an ALLOW record, which includes a list of new sources from which the interface wishes to receive traffic. It can also

contain a BLOCK record, which lists the current traffic sources from which the interface wants to stop receiving traffic.

IGMP protocols provide a method for clients and a device to exchange messages, and let the device build a database indicating which

port wants what traffic. The protocols do not specify forwarding methods. They require IGMP snooping or multicast protocols such as

PIM to handle packet forwarding. PIM can route multicast packets within and outside a VLAN, while IGMP snooping can switch packets

only within a VLAN.

If a VLAN is not IGMP snooping-enabled, it floods multicast data and control packets to the entire VLAN in hardware. When snooping is

enabled, IGMP packets are trapped to the CPU. Data packets are mirrored to the CPU in addition to being VLAN flooded. The CPU then

installs hardware resources, so that subsequent data packets can be switched to desired ports in hardware without going to the CPU. If

there is no client report or port to queriers for a data stream, the hardware resource drops it.

Queriers and non-queriers

An IGMP snooping-enabled Brocade device can be configured as a querier (active) or non-querier (passive). An IGMP querier sends

queries; a non-querier listens for IGMP queries and forwards them to the entire VLAN. VLANs can be independently configured to be

queriers or non-queriers. If a VLAN has a connection to a PIM-enabled port on another router, the VLAN must be configured as a non-

querier. When multiple IGMP snooping devices are connected together, and there is no connection to a PIM-enabled port, one of the

devices must be configured as a querier. If multiple devices are configured as queriers, after these devices exchange queries, then all

except the winner stop sending queries. The device with the lowest address becomes the querier. Although the system will work when

multiple devices are configured as queriers, Brocade recommends that only one device (preferably the one with the traffic source) is

configured as a querier.

The non-queriers always forward multicast data traffic and IGMP messages to router ports which receive IGMP queries or PIM hellos.

Brocade recommends that you configure the device with the data traffic source (server) as a querier. If a server is attached to a non-

querier, the non-querier always forwards traffic to the querier regardless of whether there are any clients on the querier.

NOTE

In a topology of one or more connecting devices, at least one device must be running PIM configured as active. Otherwise,

none of the devices can send out queries, and traffic cannot be forwarded to clients.

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VLAN-specific configuration

IGMP snooping can be enabled on some VLANs or on all VLANs. Each VLAN can be independently configured to be a querier or non-

querier and can be configured for IGMP V2 or IGMP V3. In general, the ip multicast commands apply globally to all VLANs except

those configured with VLAN-specific multicast commands. The VLAN-specific multicast commands supersede the global ip multicast

commands.

IGMP snooping can be configured for IGMP V2 or IGMP V3 on individual ports of a VLAN. An interface or router sends the queries and

reports that include its IGMP version specified on it. The version configuration only applies to sending queries. The snooping device

recognizes and processes IGMP V2 and IGMP V3 packets regardless of the version configuration.

To avoid version deadlock, an interface retains its version configuration even when it receives a report with a lower version.

Tracking and fast leave

Brocade devices support fast leave for IGMP V2, and tracking and fast leave for IGMP V3. Fast leave stops the traffic immediately when

the port receives a leave message. Tracking traces all IGMP V3 clients. Refer to Enabling IGMP V3 membership tracking and fast leave

for the VLAN on page 25 and Enabling fast leave for IGMP V2 on page 26.

Support for IGMP snooping and Layer 3 multicast routing together on the same device

The Brocade device supports global Layer 2 IP multicast traffic reduction (IGMP snoopoing) and Layer 3 multicast routing (PIM-Sparse

or PIM-Dense) together on the same device in the full Layer 3 software image, as long as the Layer 2 feature configuration is at the

VLAN level.

Forwarding mechanism in hardware

IP-based forwarding implementation on FCX and ICX devices

The following information about *,G or S,G fdb-based implementation is specific to FCX, ICX 6610, ICX 6430, and ICX 6450 devices.

On both switch and router software images, IGMP snooping is either *,G based or S,G based. The hardware can either match the group

address only (* G), or both the source and group (S, G) of the data stream. This is 32-bit IP address matching, not 23-bit multicast MAC

address 01-00-5e-xx-xx-xx matching.

When any port in a VLAN is configured for IGMP v3, the VLAN matches both source and group (S, G) in hardware switching. If no ports

are configured for IGMP v3, the VLAN matches group only (* G). Matching (S, G) requires more hardware resources than matching (* G)

when there are multiple servers sharing the same group. For example, two data streams from different sources to the same group

require two (S, G) entries in IGMP v3, but only one (* G) entry in IGMP v2.

To conserve resources, IGMP v3 must be used only in source-specific applications. When VLANs are independently configured for

versions, some VLANs can match (* G) while others match (S, G).

MAC-based forwarding implementation on FastIron X Series devices

On both switch and router software images, IGMP snooping is MAC-based. This differs from IGMP snooping on the BigIron router

images, which match on both IP source and group (S,G) entries programmed in the Layer 4 CAM.

This differs from IGMP snooping on the FastIron FCX/ICX router images, which match on both IP source and group (S,G) entries. In

contrast, the FastIron X Series images match on Layer 2 23-bit multicast MAC address i.e. 01-00-5e-xx-xx-xx (*,G) entries.

In addition, the lowest 23 bits of the group address are mapped to a MAC address. In this way, multiple groups (for example, 224.1.1.1

and 225.1.1.1) have the same MAC address. Groups having the same MAC address are switched to the same destination ports, which are

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the superset of individual group output ports. Thus, the use of Layer 2 CAM might cause unwanted packets to be sent to some ports.

However, the switch generally needs far less layer 2 mac entries than it does for IP-based forwarding, which is required for each stream

with a different source and group.

Hardware resources for IGMP and PIM-SM snooping

Brocade devices allocate/program fdb/mac entries and application VLAN (vidx) to achieve multicast snooping in hardware. If a data

packet does not match any of these resources, it might be sent to the CPU, which increases the CPU burden. This can happen if the

device runs out of hardware resources, or is unable to install resources for a specific matching address due to a hashing collision.

The hardware hashes addresses into available fdb/mac entries, with some addresses hashed into the same entry. If the collision number

in an entry is more than the hardware chain length, the resource cannot be installed.

Configuration notes and feature limitations for IGMP snooping and Layer 3 multicast

routing

The following notes apply to all devices:

∙Layer 2 IGMP multicast is automatically enabled with Layer 3 multicast routing. If Layer 3 multicast routing is enabled on your

system, do not attempt to enable Layer 2 IGMP snooping.

∙The default IGMP version is V2.

∙A user can configure the maximum numbers of group address entries.

∙An IGMP device can be configured to rate-limit the forwarding IGMP V2 membership reports to queriers.

∙The device supports static groups. The device acts as a proxy to send IGMP reports for the static groups when receiving

queries.

∙A user can configure static router ports to force all multicast traffic to these specific ports.

∙If a VLAN has a connection to a PIM-enabled port on another router, the VLAN must be configured as a non-querier (passive).

When multiple snooping devices connect together and there is no connection to PIM ports, one device must be configured as a

querier (active). If multiple devices are configured as active (queriers), only one will keep sending queries after exchanging

queries.

∙The querier must configure an IP address to send out queries.

∙IGMP snooping requires hardware resource. Hardware resource is installed only when there is data traffic. If resource is

inadequate, the data stream without a resource is mirrored to the CPU in addition to being VLAN flooded, which can cause high

CPU usage. Brocade recommends that you avoid global enabling of snooping unless necessary.

∙IGMP snooping requires clients to send membership reports in order to receive data traffic. If a client application does not send

reports, you must configure static groups on the snooping VLAN to force traffic to client ports. Note that servers (traffic

sources) are not required to send IGMP memberships.

∙Support for VSRP together with IGMP snooping on the same interface.

∙When VSRP or VSRP-aware is configured on a VLAN, only IGMP version 2 is recommended; IGMP version 3 is not

recommended.

∙Each VLAN can independently enable or disable IGMP, or configure IGMP v2 or IGMP v3.

∙IGMP/PIM-SM snooping over Multi-Chassis Trunking is supported on FSX 800, FSX 1600, ICX 6650, and ICX 7750 devices.

The following details apply to FCX, ICX 6610, ICX 6430, ICX 6450, and ICX 6650 devices:

∙Using the drop option, you can configure a static group that can discard multicast data packets to a specified group in hardware,

including addresses in the reserved range.

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The following details apply to FastIron X Series devices:

∙High CPU utilization occurs when IGMP Snooping and PIM routing are enabled simultaneously, and if the ingressing VLAN of

the snooping traffic has "router-interface" configuration. With this configuration, IP Multicast data packets received in the

snooping VLANs are forwarded to client ports via the hardware; however, copies of these packets are received and dropped by

the CPU.

IGMP snooping configuration

Configuring IGMP snooping on a Brocade device consists of the following global, VLAN-specific, and port-specific tasks:

Perform the following global IGMP snooping tasks:

∙Configuring the IGMP V3 snooping software resource limits

∙Enabling IGMP snooping globally on the device

∙Configuring the global IGMP mode

∙Configuring the global IGMP version

∙Modifying the age interval for group membership entries

∙Modifying the query interval (active IGMP snooping mode only)

∙Modifying the maximum response time

∙Configuring report control (rate limiting)

∙Modifying the wait time before stopping traffic when receiving a leave message

∙Modifying the multicast cache age time

∙Enabling or disabling error and warning messages

Perform the following VLAN-specific IGMP snooping tasks:

∙Configuring the IGMP mode for a VLAN (active or passive)

∙Disabling IGMP snooping on a VLAN

∙Configuring the IGMP version for a VLAN

∙Configuring static router ports

∙Turning off static group proxy

∙Enabling IGMP V3 membership tracking and fast leave for the VLAN

∙Enabling fast leave for IGMP

∙Enabling fast convergence

Perform the following port-specific IGMP snooping task:

∙Configuring the IGMP version for individual ports in a VLAN

IGMP snooping mcache entries and group addresses

An IGMP snooping group address entry is created when an IGMP join message is received for a group. An IGMP snooping mcache

entry is created when data traffic is received for that group. Each mcache entry represents one data stream, and multiple mcache entries

(up to 32) can share the same hardware (MAC) address entry. The egress port list for the mcache entry is obtained from the IGMP group

address entry. If there is no existing IGMP group address entry when an mcache entry is created, data traffic for that multicast group is

dropped in hardware. If there is an existing IGMP group address entry when an mcache is created, data traffic for that multicast group is

switched in hardware.

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IGMP snooping software resource limits

These are the IGMP snooping mcache resource limits for Brocade devices.

∙FCX, FSX, ICX 6610, and ICX 6450 devices support up to 8192 IGMP snooping mcache entries.

∙ICX 6430 devices support up to 2048 IGMP snooping mcache entries.

∙ICX 6650 devices support 8192 IGMP snooping mcache entries.

∙ICX 7750 switches support 8192 IGMP snooping mcache entries.

∙ICX 7750 routers support 6K IGMP snooping mcache entries.

∙ICX 7250 devices support 8192 IGMP snooping mcache entries.

∙ICX 7450 devices support 8192 IGMP snooping mcache entries.

Changing the maximum number of supported IGMP snooping mcache entries

You can configure the system-max igmp-snoop-mcache command to change the maximum number of IGMP snooping cache entries

supported on a device.

Device(config)#system-max igmp-snoop-mcache 2000

Syntax: [no] system-max igmp-snoop-mcache

num

The

num

variable is a value from 256 through 8192. The default is 512.

Setting the maximum number of IGMP group addresses

The configured number of IGMP group addresses is the upper limit of an expandable database. Client memberships exceeding the

group limit are not processed. Configure the system-max igmp-snoop-group-addr command to define the maximum number of IGMP

group addresses.

Device(config)#system-max igmp-snoop-group-addr 1600

Syntax: [no] system-max igmp-snoop-group-addr

num

The

num

variable is a value from 256 to 8192. The default for IGMP snooping group addresses is 4096, except for ICX 6430 devices

where the default is 1024.

Enabling IGMP snooping globally on the device

When you globally enable IGMP snooping, you can specify IGMP V2 or IGMP V3. The ip multicast version command enables IGMP

V3.

device(config)#ip multicast version 3

Syntax: [no] ip multicast version [2 | 3]

If you do not specify a version number, IGMP V2 is assumed.

Configuration notes for Layer 3 devices

∙If Layer 3 multicast routing is enabled on your system, do not attempt to enable Layer 2 IGMP snooping. Layer 2 IGMP

snooping is automatically enabled with Layer 3 multicast routing.

∙If the "route-only" feature is enabled on the Layer 3 Switch, then IP multicast traffic reduction will not be supported.

∙IGMP snooping is not supported on the default VLAN of Layer 3 Switches.

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Disabling the flooding of unregistered IPv6 multicast frames in an MLD-snooping-enabled VLAN

NOTE

Disabling the flooding of unregistered IPv6 multicast frames in an MLD-snooping-enabled VLAN is supported only on the

following platforms:

∙The Brocade ICX 6650

∙The Brocade ICX 7750 (standalone and stacking)

Support for this feature on the Brocade ICX 7750 was introduced in FastIron 8.0.10d. In releases prior to FastIron 8.0.30,

support for this feature on the Brocade ICX 7750 was for devices in standalone mode only.

To disable the flooding of unregistered IPv6 multicast frames in an MLD-snooping-enabled VLAN, use the ipv6 multicast disable-

flooding command in global configuration mode.

The following example disables flooding of unregistered IPv6 multicast frames.

Device(config)# ipv6 multicast disable-flooding

Configuring the IGMP mode

You can configure active or passive IGMP modes on the Brocade device. The default mode is passive. If you specify an IGMP mode for

a VLAN, it overrides the global setting.

∙Active - When active IGMP mode is enabled, a Brocade device actively sends out IGMP queries to identify multicast groups on

the network, and makes entries in the IGMP table based on the group membership reports it receives.

NOTE

Routers in the network generally handle this operation. Use the active IGMP mode only when the device is in a stand-alone

Layer 2 Switched network with no external IP multicast router attachments. In this case, enable the active IGMP mode on only

one of the devices and leave the other devices configured for passive IGMP mode.

∙Passive - When passive IGMP mode is enabled, it forwards reports to the router ports which receive queries. IGMP snooping in

the passive mode does not send queries. However, it forwards queries to the entire VLAN.

Configuring the global IGMP mode

To globally set the IGMP mode to active, enter the following command.

device(config)#ip multicast active

Syntax: [no] ip multicast [ active | passive ]

If you do not enter either active or passive, the passive mode is assumed.

Configuring the IGMP mode for a VLAN

If you specify an IGMP mode for a VLAN, it overrides the global setting.

To set the IGMP mode for VLAN 20 to active, enter the following commands.

device(config)#vlan 20

device(config-vlan-20)#multicast active

Syntax: [no] multicast [ active | passive]

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Configuring the IGMP version

Use the procedures in this section to specify the IGMP version.

Configuring the global IGMP version

To globally specify IGMP V2 or IGMP V3, refer to Enabling IGMP snooping globally on the device on page 20.

Configuring the IGMP version for a VLAN

You can specify the IGMP version for a VLAN. For example, the following commands configure VLAN 20 to use IGMP V3.

device(config)#vlan 20

device(config-vlan-20)#multicast version 3

Syntax: [no] multicast version [2 | 3 ]

If no IGMP version is specified, then the globally-configured IGMP version is used. If an IGMP version is specified for individual ports,

those ports use that version, instead of the VLAN version.

Configuring the IGMP version for individual ports in a VLAN

You can specify the IGMP version for individual ports in a VLAN. For example, the following commands configure ports 1/2/4, 1/2/5,

and 1/2/6 to use IGMP V3. The other ports either use the IGMP version specified with the multicast version command, or the globally-

configured IGMP version.

device(config)#vlan 20

device(config-vlan-20)#multicast port-version 3 ethernet 1/2/4 to 1/2/6

Syntax: [no] multicast port-version [2 | 3 ] ethernet

unit/slot/port

[ethernet

unit/slot/port

| to

unit/slot/port

]

To specify a list of ports, enter each port as ethernet

unit/slot/port

followed by a space. For example, ethernet 1/1/24 ethernet 1/3/24

ethernet 1/4/17.

To specify a range of ports, enter the first port in the range as ethernet

port

followed by the last port in the range. For example, ethernet

1/1/1 to 1/1/8.

You can combine lists and ranges in the same command. For example: enable ethernet 1/1/1 to 1/1/8 ethernet 1/1/24 ethernet 1/4/24

ethernet 1/4/17.

Configuring static groups to specific ports

A snooping-enabled VLAN cannot forward multicast traffic to ports that do not receive IGMP membership reports. If clients cannot send

reports, you can configure a static group which applies to specific ports. The static group allows packets to be forwarded to the static

group ports even though they have no client membership reports.

device(config)#vlan 20

device(config-vlan-20)#multicast static-group 224.1.1.1 count 2 ethernet 1/1/3 ethernet 1/1/5 to 1/1/7

Information specific to FCX and ICX devices

The following information about the drop option is specific to FCX, ICX 6610, ICX 6430, ICX 6450, and ICX 6650 devices.

The static group drop option discards data traffic to a group in hardware. The group can be any multicast group including groups in the

reserved range of 224.0.0.X. The drop option does not apply to IGMP packets, which are always trapped to CPU when snooping is

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enabled. The drop option applies to the entire VLAN, and cannot be configured for a port list. When the drop option is not specified, the

group must exist outside the reserved range.

device(config-vlan-20)#multicast static-group 239.1.1.1 count 3 drop

Syntax: [no] multicast static-group

ipv4-address

[ count

num

] [

unit/slot/port

| drop ]

The

ipv4-address

parameter is the address of the multicast group.

The count is optional, which allows a contiguous range of groups. Omitting the count

num

is equivalent to the count being 1.

Disabling IGMP snooping on a VLAN

When IGMP snooping is enabled globally, you can still disable it for a specific VLAN. For example, the following commands cause IGMP

snooping to be disabled for VLAN 20. This setting overrides the global setting.

device(config)#vlan 20

device(config-vlan-20)#multicast disable-multicast-snoop

Syntax: [no] multicast disable-multicast-snoop

Modifying the age interval for group membership entries

When the device receives a group membership report, it makes an entry for that group in the IGMP group table. The age interval

specifies how long the entry can remain in the table before the device receives another group membership report. When multiple devices

connect together, all devices must be configured for the same age interval, which must be at least twice the length of the query interval,

so that missing one report won't stop traffic. Non-querier age intervals must be the same as the age interval of the querier.

To modify the age interval, enter the following command.

device(config)#ip multicast age-interval 280

Syntax: [no] ip multicast age-interval

interval

The

interval

parameter specifies the aging time. You can specify a value from 20 through 26000 seconds. The default is 260 seconds.

Modifying the query interval (active IGMP snooping mode only)

If IP multicast traffic reduction is set to active mode, you can modify the query interval to specify how often the device sends general

queries. When multiple queriers connect together, they must all be configured with the same query interval.

To modify the query interval, enter the following command.

device(config)#ip multicast query-interval 120

Syntax: [no] ip multicast query-interval

interval

The

interval

parameter specifies the time between queries. You can specify a value from 10 through 3600 seconds. The default is 125

seconds.

Modifying the maximum response time

The maximum response time is the number of seconds that a client can wait before responding to a query sent by the switch.

To change the maximum response time, enter the following command.

device(config)#ip multicast max-response-time 5

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Syntax: [no] ip multicast max-response-time

interval

For

interval

, enter a value from 1 through 10 seconds. The default is 10 seconds.

Configuring report control

A device in passive mode forwards reports and leave messages from clients to the upstream router ports that are receiving queries.

You can configure report control to rate-limit report forwarding within the same group to no more than once every 10 seconds. This rate-

limiting does not apply to the first report answering a group-specific query.

NOTE

This feature applies to IGMP V2 only. The leave messages are not rate limited.

IGMP V2 membership reports of the same group from different clients are considered to be the same and are rate-limited.

Use the ip multicast report-control command to alleviate report storms from many clients answering the upstream router query.

device(config)#ip multicast report-control

Syntax: [no] ip multicast-report-control

The original command, ip igmp-report-control , has been renamed to ip multicast report-control . The original command is still accepted;

however, it is renamed when you configure a show configuration command.

Modifying the wait time before stopping traffic when receiving a leave message

You can define the wait time before stopping traffic to a port when a leave message is received. The device sends group-specific queries

once per second to ask if any client in the same port still needs this group. Due to internal timer granularity, the actual wait time is

between n and (n+1) seconds (n is the configured value).

device(config)#ip multicast leave-wait-time 1

Syntax: [no] ip multicast leave-wait-time

num

is the number of seconds from 1 through 5. The default is 2 seconds.

Modifying the multicast cache age time

You can set the time for an mcache to age out when it does not receive traffic. The traffic is hardware switched. One minute before aging

out an mcache, the device mirrors a packet of this mcache to CPU to reset the age. If no data traffic arrives within one minute, this

mcache is deleted. A lower value quickly removes resources consumed by idle streams, but it mirrors packets to CPU often. A higher

value is recommended only data streams are continually arriving.

device(config)#ip multicast mcache-age 180

Syntax: [no] ip multicast mcache-age

num

is the number of seconds from 60 through 3600. The default is 60 seconds.

Enabling or disabling error and warning messages

The device prints error or warning messages when it runs out of software resources or when it receives packets with the wrong

checksum or groups. These messages are rate-limited. You can turn off these messages by entering the following command.

device(config)#ip multicast verbose-off

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Syntax: [no] ip multicast verbose-off

Configuring static router ports

The Brocade device forwards all multicast control and data packets to router ports which receive queries. Although router ports are

learned, you can force multicast traffic to specified ports even though these ports never receive queries. To configure static router ports,

enter the following commands.

device(config)#vlan 70

device(config-vlan-70)#multicast router-port ethernet 1/1/4 to 1/1/5 ethernet 1/1/8

Syntax: [no] multicast router-port ethernet

unit/slot/port

[ ethernet

unit/slot/port

| to

unit/slot/port

]

To specify a list of ports, enter each port as ethernet

unit/slot/port

followed by a space. For example, ethernet

1/1/24

ethernet

1/2//17

ethernet

1/4/24

To specify a range of ports, enter the first port in the range as ethernet

unit/slot/port

followed by the last port in the range. For example,

ethernet

1/1/1

1/1/8

You can combine lists and ranges in the same command. For example, enable ethernet

1/1/1

1/1/8

ethernet

1//1/24

ethernet

1/2/17

ethernet

1/4/24

Turning off static group proxy

If a device has been configured for static groups, it acts as a proxy and sends membership reports for the static groups when it receives

general or group-specific queries. When a static group configuration is removed, it is deleted from the active group table immediately.

However, leave messages are not sent to the querier, and the querier must age out the group. Proxy activity can be turned off. The

default is on. To turn proxy activity off for VLAN 20, enter the following commands.

device(config)#vlan 20

device(config-vlan-20)#multicast proxy-off

Syntax: [no] multicast proxy-off

Enabling IGMP V3 membership tracking and fast leave for the VLAN

IGMP V3 gives clients membership tracking and fast leave capability. In IGMP V2, only one client on an interface needs to respond to a

router's queries. This can leave some clients invisible to the router, making it impossible to track the membership of all clients in a group.

When a client leaves the group, the device sends group-specific queries to the interface to see if other clients on that interface need the

data stream of the client who is leaving. If no client responds, the device waits a few seconds before it stops the traffic. You can configure

the wait time using the ip multicast leave-wait-time command.

IGMP V3 requires every client to respond to queries, allowing the device to track all clients. When tracking is enabled, and an IGMP V3

client sends a leave message and there is no other client, the device immediately stops forwarding traffic to the interface. This feature

requires the entire VLAN be configured for IGMP V3 with no IGMP V2 clients. If a client does not send a report during the specified

group membership time (the default is 260 seconds), that client is removed from the tracking list.

Every group on a physical port keeps its own tracking record. However, it can only track group membership; it cannot track by (source,

group). For example, Client A and Client B belong to group1 but each receives traffic streams from different sources. Client A receives a

stream from (source_1, group1) and Client B receives a stream from (source_2, group1). The device still waits for the configured leave-

wait-time before it stops the traffic because these two clients are in the same group. If the clients are in different groups, then the waiting

period is not applied and traffic is stopped immediately.

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To enable the tracking and fast leave feature for VLAN 20, enter the following commands.

device(config)#vlan 20

device(config-vlan-20)#multicast tracking

Syntax: [no] multicast tracking

The membership tracking and fast leave features are supported for IGMP V3 only. If any port or any client is not configured for IGMP

V3, then the multicast tracking command is ignored.

Enabling fast leave for IGMP V2

When a device receives an IGMP V2 leave message, it sends out multiple group-specific queries. If no other client replies within the

waiting period, the device stops forwarding traffic. When fast-leave-v2 is configured, and when the device receives a leave message, it

immediately stops forwarding to that port. The device does not send group specific-queries. When fast-leave-v2 is configured on a

VLAN, you must not have multiple clients on any port that is part of the VLAN. In a scenario where two devices connect, the querier

device should not be configured for fast-leave-v2 because the port might have multiple clients through the non-querier. The number of

queries, and the waiting period (in seconds) can be configured using the ip multicast leave-wait-time command. The default is 2

seconds.

To configure fast leave for IGMP V2, enter the following commands.

device(config)#vlan 20

device(config-vlan-20)#multicast fast-leave-v2

Syntax: [no] multicast fast-leave-v2

Enabling fast convergence

In addition to sending periodic general queries, an active device sends general queries when it detects a new port. However, because the

device does not recognize the other device's port up event, multicast traffic might still require up to the query-interval time to resume

after a topology change. Fast convergence allows the device to listen to topology change events in Layer 2 protocols such as spanning

tree, and then send general queries to shorten the convergence time.

If the Layer 2 protocol cannot detect a topology change, fast convergence may not work in some cases. For example, if the direct

connection between two devices switches from one interface to another, the rapid spanning tree protocol (802.1w) considers this

optimization, rather than a topology change. In this example, other devices will not receive topology change notifications, and will be

unable to send queries to speed up the convergence. Fast convergence works well with the regular spanning tree protocol in this case.

To enable fast-convergency, enter the following commands.

device(config)#vlan 70

device(config-vlan-70)#multicast fast-convergence

Syntax: multicast fast-convergence

IGMP snooping show commands

This section describes the show commands for IGMP snooping.

Displaying the IGMP snooping configuration

To display the global IGMP snooping configuration, enter the show ip multicast command at any level of the CLI.

device#show ip multicast

Summary of all vlans. Please use "sh ip mu vlan vlan-id" for details

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Version=2, Intervals: Query=125, Group Age=260, Max Resp=10, Other Qr=260

VL10: cfg V3, vlan cfg passive, , pimsm (vlan cfg), 1 grp, 0 (SG) cache, no rtr port

To display the IGMP snooping information for a specific VLAN, enter the following command.

device#show ip multicast vlan 10

Version=3, Intervals: Query=10, Group Age=260, Max Resp=10, Other Qr=30

VL10: cfg V3, vlan cfg passive, , pimsm (vlan cfg), 3 grp, 1 (SG) cache, no rtr port,

e1/1/2 has 3 groups, non-QR (passive), default V3

**** Warning! has V2 client (life=240),

group: 239.0.0.3, life = 240

group: 224.1.1.2, life = 240

group: 224.1.1.1, life = 240

e1/1/4 has 0 groups, non-QR (passive), default V3

Syntax: show ip multicast vlan

vlan-id

If you do not specify a

vlan-id

, information for all VLANs is displayed.

The following table describes the information displayed by the show ip multicast vlan command.

Field Description

Version The global IGMP version. In this example, the device is configured for

IGMP version 2.

Query How often a querier sends a general query on the interface. In this

example, the general queries are sent every 125 seconds.

Group Age The number of seconds membership groups can be members of this

group before aging out.

Max Resp The maximum number of seconds a client waits before replying to a

query.

Other Qr How long it took a switch with a lower IP address to become a new

querier. This value is 2 x Query + Max Resp.

cfg The IGMP version for the specified VLAN. In this example, VL10: cfg V3

indicates that VLAN 10 is configured for IGMP V3.

vlan cfg The IGMP configuration mode, which is either passive or active.

pimsm Indicates that PIM SM is enabled on the VLAN.

rtr port The router ports, which are the ports receiving queries.

Displaying IGMP snooping errors

To display information about possible IGMP errors, enter the show ip multicast error command.

device#show ip multicast error

snoop SW processed pkt: 173, up-time 160 sec

Syntax: show ip multicast error

The following table describes the output from the show ip multicast error command.

Field Description

SW processed pkt The number of multicast packets processed by IGMP snooping.

up-time The time since the IGMP snooping is enabled.

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Displaying IGMP group information

To display default, maximum, current, and configured values for system maximum parameters, use the show default values command.

The following output example does not show complete output; it shows only IGMP group values.

device(config)#show default values

System Parameters Default Maximum Current Configured

igmp-snoop-group-add 4096 8192 5000 5000

To display information about IGMP groups, enter the show ip multicast group command.

device#show ip multicast group

p-:physical, ST:static, QR:querier, EX:exclude, IN:include, Y:yes, N:no

VL70 : 3 groups, 4 group-port, tracking_enabled

group p-port ST QR life mode source

1 224.1.1.2 1/33 no yes 120 EX 0

2 224.1.1.1 1/33 no yes 120 EX 0

3 226.1.1.1 1/35 yes yes 100 EX 0

4 226.1.1.1 1/33 yes yes 100 EX 0

In this example, an IGMP V2 group is in EXCLUDE mode with a source of 0. The group only excludes traffic from the 0 (zero) source

list, which actually means that all traffic sources are included.

To display detailed IGMP group information for a specific group, enter the show ip multicast group detail command.

device#show ip multicast group 226.1.1.1 detail

Display group 226.1.1.1 in all interfaces in details.

p-:physical, ST:static, QR:querier, EX:exclude, IN:include, Y:yes, N:no

VL70 : 1 groups, 2 group-port, tracking_enabled

group p-port ST QR life mode source

1 226.1.1.1 1/35 yes yes 120 EX 0

group: 226.1.1.1, EX, permit 0 (source, life):

life=120, deny 0:

group p-port ST QR life mode source

2 226.1.1.1 1/33 yes yes 120 EX 0

group: 226.1.1.1, EX, permit 0 (source, life):

life=120, deny 0:

If the tracking and fast leave features are enabled, you can display the list of clients that belong to a particular group by entering the

following command.

device#show ip multicast group 224.1.1.1 tracking

Display group 224.1.1.1 in all interfaces with tracking enabled.

p-:physical, ST:static, QR:querier, EX:exclude, IN:include, Y:yes, N:no

VL70 : 1 groups, 1 group-port, tracking_enabled

group p-port ST QR life mode source

*** Note: has 1 static groups to the entire vlan, not displayed here

1 224.1.1.1 1/33 no yes 100 EX 0

receive reports from 1 clients: (age)

(10.2.100.2 60)

Syntax: show ip multicast group [

group-address

[detail] [tracking]]

If you want a report for a specific multicast group, enter that group's address for

group-address

Enter detail to display the source list of a specific VLAN.

Enter tracking for information on interfaces that have tracking enabled.

The following table describes the information displayed by the show ip multicast group command.

Field Description

group The address of the group (destination address in this case, 224.1.1.1)

p-port The physical port on which the group membership was received.

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Field Description

ST Yes indicates that the IGMP group was configured as a static group; No

means the address was learned from reports.

QR Yes means the port is a querier port; No means it is not. A port becomes a

non-querier port when it receives a query from a source with a lower

source IP address than the device.

life The number of seconds the group can remain in EXCLUDE mode. An

EXCLUDE mode changes to INCLUDE mode if it does not receive an

"IS_EX" or "TO_EX" message during a certain period of time. The default

is 260 seconds. There is no life displayed in INCLUDE mode.

mode Indicates current mode of the interface: INCLUDE or EXCLUDE. If the

interface is in INCLUDE mode, it admits traffic only from the source list. If

an interface is in EXCLUDE mode, it denies traffic from the source list and

accepts the rest.

source Identifies the source list that will be included or excluded on the interface.

For example, if an IGMP V2 group is in EXCLUDE mode with a source of

0, the group excludes traffic from the 0 (zero) source list, which actually

means that all traffic sources are included.

Displaying IGMP snooping mcache information

To display default, maximum, current, and configured values for system maximum parameters, use the show default values command.

The following output example does not show complete output; it shows only IGMP mcache values.

device(config)#show default values

System Parameters Default Maximum Current Configured

igmp-snoop-mcache 512 8192 300 300

The IGMP snooping mcache contains multicast forwarding information for VLANs. To display information in the multicast forwarding

mcache, enter the show ip multicast mcache command.

device#show ip multicast mcache

Example: (S G) cnt=: cnt is number of SW processed packets

OIF: e1/1/22 TR(1/1/32,1/1/33), TR is trunk, e1/1/32 primary, e1/1/33 output

vlan 10, 1 caches. use 1 VIDX

1 (10.10.10.2 239.0.0.3) cnt=0

OIF: tag e2

age=2s up-time=2s change=2s vidx=8191 (ref-cnt=1)

Syntax: show ip multicast mcache

The following table describes the output of the show ip multicast mcache command.

Field Description

(source group) Source and group addresses of this data stream. (* group) means match

group only; (source group) means match both.

cnt The number of packets processed in software. Packets are switched in

hardware, which increases this number slowly.

OIF The output interfaces. If entire vlan is displayed, this indicates that

static groups apply to the entire VLAN.

age The mcache age. The mcache will be reset to 0 if traffic continues to

arrive, otherwise the mcache will be aged out when it reaches the time

defined by the ip multicast mcache-age command.

uptime The up time of this mcache in seconds.

vidx Vidx specifies output port list index. Range is from 4096 through 8191

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Field Description

ref-cnt The vidx is shared among mcaches having the same output interfaces.

Ref-cnt indicates the number of mcaches using this vidx.

Displaying software resource usage for VLANs

To display information about the software resources used, enter the show ip multicast resource command.

device#show ip multicast resource

alloc in-use avail get-fail limit get-mem size init

igmp group 256 1 255 0 32000 1 16 256

igmp phy port 1024 1 1023 0 200000 1 22 1024

.... entries deleted ...

snoop mcache entry 128 2 126 0 8192 3 56 128

total pool memory 109056 bytes

has total 2 forwarding hash

VIDX sharing hash : size=2 anchor=997 2nd-hash=no fast-trav=no

Available vidx: 4060. IGMP/MLD use 2

Syntax: show ip multicast resource

The following table describes the output displayed by the show ip multicast resource command.

Field Description

alloc The allocated number of units.

in-use The number of units which are currently being used.

avail The number of available units.

get-fail This displays the number of resource failures.

NOTE

It is important to pay attention to this field.

limit The upper limit of this expandable field. The limit of multicast group

is configured by the system-max igmp-snoop-group-addr command.

The limit of snoop mcache entry is configured by the system-max

igmp-snoop-mcache command.

get-mem The number of memory allocation. This number must continue to

increase.

size The size of a unit (in bytes).

init The initial allocated amount of memory. More memory may be allocated if

resources run out.

Available vidx The output interface (OIF) port mask used by mcache. The entire device

has a maximum of 4096 vidx. Different mcaches with the same OIF

share the same vidx. If vidx is not available, the stream cannot be

hardware-switched.

Displaying the status of IGMP snooping traffic

To display status information for IGMP snooping traffic, enter the show ip multicast traffic command.

device#show ip multicast traffic

IGMP snooping: Total Recv: 22, Xmit: 26

Q: query, Qry: general Q, G-Qry: group Q, GSQry: group-source Q, Mbr: member

Recv QryV2 QryV3 G-Qry GSQry MbrV2 MbrV3 Leave

VL1 0 0 0 0 4 0 0

VL70 18 0 0 0 0 0 0

Recv IsIN IsEX ToIN ToEX ALLOW BLOCK Pkt-Err

VL1 0 4 0 0 0 0 0

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VL70 0 0 0 0 0 0 0

Send QryV2 QryV3 G-Qry GSQry MbrV2 MbrV3

VL1 0 0 8 0 0 0

VL70 0 0 0 0 0 18

VL70 pimsm-snooping, Hello: 12, Join/Prune: 9

Syntax: show ip multicast traffic

The following table describes the information displayed by the show ip multicast traffic command.

Field Description

Q Query

Qry General Query

QryV2 Number of general IGMP V2 queries received or sent.

QryV3 Number of general IGMP V3 queries received or sent.

G-Qry Number of group-specific queries received or sent.

GSQry Number of group source-specific queries received or sent.

Mbr The membership report.

MbrV2 The IGMP V2 membership report.

MbrV3 The IGMP V3 membership report.

IsIN Number of source addresses that were included in the traffic.

IsEX Number of source addresses that were excluded in the traffic.

ToIN Number of times the interface mode changed from EXCLUDE to

INCLUDE.

ToEX Number of times the interface mode changed from INCLUDE to

EXCLUDE.

ALLO Number of times that additional source addresses were allowed on the

interface.

BLK Number of times that sources were removed from an interface.

Pkt-Err Number of packets having errors, such as checksum.

Pimsm-snooping hello, join, prune Number of PIM sparse hello, join, and prune packets

Displaying querier information

You can use the show ip multicast vlan command to display the querier information for a VLAN. This command displays the VLAN

interface status and if there is any other querier present with the lowest IP address. The following list provides the combinations of

querier possibilities:

∙Active Interface with no other querier present

∙Passive Interface with no other querier present

∙Active Interface with other querier present

∙Passive Interface with other querier present

Displaying the active interface with no other querier present

The following example shows the output in which the VLAN interface is active and no other querier is present with the lowest IP address.

device#show ip multicast vlan 10

Version=2, Intervals: Query=125, Group Age=260, Max Resp=10, Other Qr=260

VL10: dft

V2, vlan cfg active, 0 grp, 0 (*G) cache, no rtr port,

1/1/16 has 0 groups,

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This interface is Querier

default V2

1/1/24 has 0 groups,

This interface is Querier

default V2

2/1/16 has 0 groups,

This interface is Querier

default V2

2/1/24 has 0 groups,

This interface is Querier

default V2

3/1/1 has 0 groups,

This interface is Querier

default V2

3/1/4 has 0 groups,

This interface is Querier

default V2

Syntax: show ip multicast vlan

vlan-id

If you do not specify a

vlan-id

, information for all VLANs is displayed.

Displaying the passive interface with no other querier present

The following example shows the output in which the VLAN interface is passive and no other querier is present with the lowest IP

address.

device#show ip multicast vlan 10

Version=2, Intervals: Query=125, Group Age=260, Max Resp=10, Other Qr=260

VL10: dft V2, vlan cfg passive, 0 grp, 0 (*G) cache, no rtr port,

1/1/16 has 0 groups,

This interface is non-Querier (passive)

default V2

1/1/24 has 0 groups,

This interface is non-Querier (passive)

default V2

2/1/16 has 0 groups,

This interface is non-Querier (passive)

default V2

2/1/24 has 0 groups,

This interface is non-Querier (passive)

default V2

3/1/1 has 0 groups,

This interface is non-Querier (passive)

default V2

3/1/4 has 0 groups,

This interface is non-Querier (passive)

default V2

Displaying the active Interface with other querier present

The following example shows the output in which the VLAN interface is active and another querier is present with the lowest IP address.

device#show ip multicast vlan 10

Version=2, Intervals: Query=125, Group Age=260, Max Resp=10, Other Qr=260

VL10: dft V2, vlan cfg active, 7 grp, 6 (*G) cache, rtr ports,

router ports: 2/1/24(260) 10.5.5.5, 3/1/4(260) 10.8.8.8,

1/1/16 has 4 groups,

This interface is Querier

default V2

group: 226.6.6.6, life = 240

group: 228.8.8.8, life = 240

group: 230.0.0.0, life = 240

group: 224.4.4.4, life = 240

1/1/24 has 1 groups,

This interface is Querier

default V2

group: 228.8.8.8, life = 240

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2/1/16 has 4 groups,

This interface is Querier

default V2

group: 226.6.6.6, life = 240

group: 228.8.8.8, life = 240

group: 230.0.0.0, life = 240

group: 224.4.4.4, life = 240

2/1/24 has 2 groups,

This interface is non-Querier

Querier is 10.5.5.5

Age is 0

Max response time is 100

default V2

**** Warning! has V3 (age=0) nbrs

group: 234.4.4.4, life = 260

group: 226.6.6.6, life = 260

3/1/1 has 4 groups,

This interface is Querier

default V2

group: 238.8.8.8, life = 260

group: 228.8.8.8, life = 260

group: 230.0.0.0, life = 260

group: 224.4.4.4, life = 260

3/1/4 has 1 groups,

This interface is non-Querier

Querier is 10.8.8.8

Age is 0

Max response time is 100

default V2

**** Warning! has V3 (age=0) nbrs

group: 236.6.6.6, life = 260

Displaying the passive interface with other querier present

The following example shows the output in which the VLAN interface is passive and another querier is present with the lowest IP

address.

device#show ip multicast vlan 10

Version=2, Intervals: Query=125, Group Age=260, Max Resp=10, Other Qr=260

VL10: dft V2, vlan cfg passive, 7 grp, 6 (*G) cache, rtr ports,

router ports: 2/1/24(260) 10.5.5.5, 3/1/4(260) 10.8.8.8,

1/1/16 has 4 groups,

This interface is non-Querier (passive)

default V2

group: 226.6.6.6, life = 260

group: 228.8.8.8, life = 260

group: 230.0.0.0, life = 260

group: 224.4.4.4, life = 260

1/1/24 has 1 groups,

This interface is non-Querier (passive)

default V2

group: 228.8.8.8, life = 260

2/1/16 has 4 groups,

This interface is non-Querier (passive)

default V2

group: 226.6.6.6, life = 260

group: 228.8.8.8, life = 260

group: 230.0.0.0, life = 260

group: 224.4.4.4, life = 260

2/1/24 has 2 groups,

This interface is non-Querier (passive)

Querier is 10.5.5.5

Age is 0

Max response time is 100

default V2

**** Warning! has V3 (age=0) nbrs

group: 234.4.4.4, life = 260

group: 226.6.6.6, life = 260

3/1/1 has 4 groups,

This interface is non-Querier (passive)

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default V2

group: 238.8.8.8, life = 260

group: 228.8.8.8, life = 260

group: 230.0.0.0, life = 260

group: 224.4.4.4, life = 260

3/1/4 has 1 groups,

This interface is non-Querier (passive)

Querier is 10.8.8.8

Age is 0

Max response time is 100

default V2

**** Warning! has V3 (age=0) nbrs

group: 236.6.6.6, life = 260

Clear commands for IGMP snooping

The clear IGMP snooping commands must be used only in troubleshooting conditions, or to recover from errors.

Clearing the IGMP mcache

To clear the mcache on all VLANs, enter the clear ip multicast mcache command.

device#clear ip multicast mcache

Syntax: clear ip multicast mcache

Clearing the mcache on a specific VLAN

To clear the mcache on a specific VLAN, enter the following command.

device#clear ip multicast vlan 10 mcache

Syntax: clear ip multicast vlan

vlan-id

mcache

The

vlan-id

parameter specifies the specific VLAN in which the mcache needs to be cleared.

Clearing traffic on a specific VLAN

To clear the traffic counters on a specific VLAN, enter the following command.

device#clear ip multicast vlan 10 traffic

Syntax: clear ip multicast vlan

vlan-id

traffic

The

vlan-id

parameter specifies the specific VLAN in which traffic counters needs to be cleared.

Clearing IGMP counters on VLANs

To clear IGMP snooping on error and traffic counters for all VLANs, enter the clear ip multicast counters command.

device#clear ip multicast counters

Syntax: clear ip multicast counters

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Disabling the flooding of unregistered IPv4 multicast frames in an IGMP-

snooping-enabled VLAN

NOTE

Disabling the flooding of unregistered IPv4 multicast frames in an IGMP-snooping-enabled VLAN is supported only on the

following platforms:

∙The Brocade ICX 6650

∙The Brocade ICX 7750 (standalone and stacking)

∙The Brocade ICX 7450 (standalone and stacking)

∙The Brocade ICX 7250 (standalone and stacking)

Support for this feature on the Brocade ICX 7750 was introduced in FastIron 8.0.10d. In releases prior to FastIron 8.0.30, support for

this feature on the Brocade ICX 7750 was for devices in standalone mode only.

To disable the flooding of unregistered IPv4 multicast frames in an IGMP-snooping-enabled VLAN, use the ip multicast disable-

flooding command in global configuration mode.

The following example disables flooding of unregistered IPv4 multicast frames.

Device(config)# ip multicast disable-flooding

PIM SM traffic snooping overview

When multiple PIM sparse routers connect through a snooping-enabled device, the Brocade device always forwards multicast traffic to

these routers. For example, PIM sparse routers R1, R2, and R3 connect through a device. Assume R2 needs traffic, and R1 sends it to the

device, which forwards it to both R2 and R3, even though R3 does not need it. A PIM SM snooping-enabled device listens to join and

prune messages exchanged by PIM sparse routers, and stops traffic to the router that sends prune messages. This allows the device to

forward the data stream to R2 only.

PIM SM traffic snooping requires IGMP snooping to be enabled on the device. IGMP snooping configures the device to listen for IGMP

messages. PIM SM traffic snooping provides a finer level of multicast traffic control by configuring the device to listen specifically for

PIM SM join and prune messages sent from one PIM SM router to another through the device.

Application examples of PIM SM traffic snooping

Figure 1 shows an example application of the PIM SM traffic snooping feature. In this example, a device is connected through an IP

router to a PIM SM group source that is sending traffic for two PIM SM groups. The device also is connected to a receiver for each of

the groups.

When PIM SM traffic snooping is enabled, the device starts listening for PIM SM join and prune messages and IGMP group

membership reports. Until the device receives a PIM SM join message or an IGMP group membership report, the device forwards IP

multicast traffic out all ports. Once the device receives a join message or group membership report for a group, the device forwards

subsequent traffic for that group only on the ports from which the join messages or IGMP reports were received.

In this example, the router connected to the receiver for group 239.255.162.1 sends a join message toward the group source. Because

PIM SM traffic snooping is enabled on the device, the device examines the join message to learn the group ID, then makes a forwarding

entry for the group ID and the port connected to the receiver router. The next time the device receives traffic for 239.255.162.1 from the

group source, the device forwards the traffic only on port 1/4/1, because that is the only port connected to a receiver for the group.

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Notice that the receiver for group 239.255.162.69 is directly connected to the device. As a result, the device does not see a join

message on behalf of the client. However, because IGMP snooping also is enabled, the device uses the IGMP group membership report

from the client to select the port for forwarding traffic to group 239.255.162.69 receivers.

The IGMP snooping feature and the PIM SM traffic snooping feature together build a list of groups and forwarding ports for the VLAN.

The list includes PIM SM groups learned through join messages as well as MAC addresses learned through IGMP group membership

reports. In this case, even though the device never sees a join message for the receiver for group 239.255.162.69, the device

nonetheless learns about the receiver and forwards group traffic to the receiver.

The device stops forwarding IP multicast traffic on a port for a group if the port receives a prune message for the group.

Notice that the ports connected to the source and the receivers are all in the same port-based VLAN on the device. This is required for

the PIM SM snooping feature. The devices on the edge of the Global Ethernet cloud are configured for IGMP snooping and PIM SM

traffic snooping. Although this application uses multiple devices, the feature has the same requirements and works the same way as it

does on a single device.

The following figure shows another example application for PIM SM traffic snooping. This example shows devices on the edge of a

Global Ethernet cloud (a Layer 2 Packet over SONET cloud). Assume that each device is attached to numerous other devices such as

other Layer 2 Switches and Layer 3 Switches (routers).

NOTE

This example assumes that the devices are actually Brocade devices running Layer 2 Switch software.

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FIGURE 1 PIM SM traffic reduction in Global Ethernet environment

The devices on the edge of the Global Ethernet cloud are configured for IGMP snooping and PIM SM traffic snooping. Although this

application uses multiple devices, the feature has the same requirements and works the same way as it does on a single device.

Configuration notes and limitations for PIM SM snooping

∙PIM SM snooping applies only to PIM SM version 2 (PIM SM V2).

∙PIM SM traffic snooping is supported in the Layer 2, base Layer 3, and full Layer 3 code.

∙IGMP snooping must be enabled on the device that will be running PIM SM snooping. The PIM SM traffic snooping feature

requires IGMP snooping.

NOTE

Use the passive mode of IGMP snooping instead of the active mode. The passive mode assumes that a router is sending

group membership queries as well as join and prune messages on behalf of receivers. The active mode configures the device

to send group membership queries.

∙All the device ports connected to the source and receivers or routers must be in the same port-based VLAN.

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∙The PIM SM snooping feature assumes that the group source and the device are in different subnets and communicate

through a router. The source must be in a different IP subnet than the receivers. A PIM SM router sends PIM join and prune

messages on behalf of a multicast group receiver only when the router and the source are in different subnet. When the

receiver and source are in the same subnet, they do not need the router in order to find one another. They find one another

directly within the subnet.

The device forwards all IP multicast traffic by default. Once you enable IGMP snooping and PIM SM traffic snooping, the device initially

blocks all PIM SM traffic instead of forwarding it. The device forwards PIM SM traffic to a receiver only when the device receives a join

message from the receiver. Consequently, if the source and the downstream router are in the same subnet, and PIM SM traffic snooping

is enabled, the device blocks the PIM SM traffic and never starts forwarding the traffic. This is because the device never receives a join

message from the downstream router for the group. The downstream router and group find each other without a join message because

they are in the same subnet.

NOTE

If the "route-only" feature is enabled on a Layer 3 Switch, PIM SM traffic snooping will not be supported.

PIM SM snooping configuration

Configuring PIM SM snooping on a Brocade device consists of the following global and VLAN-specific tasks.

Perform the following global PIM SM snooping task:

∙Enabling or disabling PIM SM snooping

Perform the following VLAN-specific PIM SM snooping tasks:

∙Enabling PIM SM snooping on a VLAN

∙Disabling PIM SM snooping on a VLAN

Enabling or disabling PIM SM snooping

Use PIM SM snooping only in topologies where multiple PIM sparse routers connect through a device. PIM SM snooping does not work

on a PIM dense mode router which does not send join messages and traffic to PIM dense ports is stopped. A PIM SM snooping-

enabled device displays a warning if it receives PIM dense join or prune messages.

To enable PIM sparse snooping globally, enter the ip pimsm-snooping command.

device(config)#ip pimsm-snooping

This command enables PIM SM traffic snooping. The PIM SM traffic snooping feature assumes that the network has routers that are

running PIM SM.

NOTE

The device must be in passive mode before it can be configured for PIM SM snooping.

To disable the feature, enter the no ip pimsm-snooping command.

device(config)#no ip pimsm-snooping

If you also want to disable IP multicast traffic reduction, enter the no ip multicast command.

device(config)#no ip multicast

Syntax: [no] ip pimsm-snooping

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Enabling PIM SM snooping on a VLAN

You can enable PIM SM snooping for a specific VLAN. For example, the following commands enable PIM SM snooping on VLAN 20.

device(config)#vlan 20

device(config-vlan-20)#multicast pimsm-snooping

Syntax: [no] multicast pimsm-snooping

Disabling PIM SM snooping on a VLAN

When PIM SM snooping is enabled globally, you can still disable it for a specific VLAN. For example, the following commands disable

PIM SM snooping for VLAN 20. This setting overrides the global setting.

device(config)#vlan 20

device(config-vlan-20)#multicast disable-pimsm-snoop

Syntax: [no] multicast disable-pimsm-snoop

PIM SM snooping show commands

This section shows how to display information about PIM SM snooping, including:

∙Displaying PIM SM snooping information on page 39

∙Displaying PIM SM snooping information on a Layer 2 switch on page 39

∙Displaying PIM SM snooping information for a specific group or source group pair on page 40

Displaying PIM SM snooping information

To display PIM SM snooping information, enter the show ip multicast pimsm-snooping command.

Device#show ip multicast pimsm-snooping

Example: Port: 7/3 (ref_count=1)

ref_count: no of entries in pimsm snoop cache added this oif)

vlan 503, has 1 caches.

1 (* 225.1.1.1) has 3 pim join ports out of 4 OIF

4/23 (ref_count=2), 4/13 (ref_count=1), 4/5 (ref_count=3),

Syntax: show ip multicast pimsm-snooping [

vlan-id

]

Use the

vlan-id

parameter to display PIM SM snooping information for a specific VLAN.

Refer to the

FastIron Command Reference

for more information on PIM SM commands.

Displaying PIM SM snooping information on a Layer 2 switch

You can display PIM SM snooping information for all groups by entering the following command at any level of the CLI on a Layer 2

Switch.

Device#show ip multicast pimsm-snooping vlan 100

VLAN 100, has 2 caches

1(*230.1.1.1) has 1 pim join ports out of 1OIF

1(age=60)

1 has 1 src: 10.20.20.66(60)

2(* 230.2.2.2) has 1 pim join ports out of 1 OIF

1(age=60)

1 has 1 src: 10.20.20.66(60)

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Syntax: show ip multicast pimsm-snooping vlan

vlan-id

Enter the ID of the VLAN for the vlan

vlan-id

parameter.

If you want to display PIM SM snooping information for one source or one group, enter a command as in the following example. The

command also displays the (source, port) list of the group.

Device#show ip multicst pimsm-snooping 230.1.1.1

Show pimsm snooping group 230.1.1.1 in all vlans

VLAN 10, has 2 caches

1(*230.1.1.1) has 1 pim join ports out of 1 OIF

1(age=120)

1 has 1 src:10.20.20.66(120)

Syntax: show ip multicast pimsm-snooping [

group-address

source-address

]

If the address you entered is within the range of source addresses, then the router treats it as the source address. Likewise, if the address

falls in the range of group addresses, then the router assumes that you are requesting a report for that group.

The following table describes the information displayed by the show ip multicast pimsm-snooping command.

Field Description

VLAN ID The port-based VLAN to which the following information applies and the

number of members in the VLAN.

PIM SM Neighbor list The PIM SM routers that are attached to the Layer 2 Switch ports.

The value following "expires" indicates how many seconds the Layer 2

Switch will wait for a hello message from the neighbor before determining

that the neighbor is no longer present and removing the neighbor from

the list.

Multicast Group The IP address of the multicast group.

NOTE

The fid and camindex values are used by Brocade Technical

Support for troubleshooting.

Forwarding Port The ports attached to the group receivers. A port is listed here when it

receives a join message for the group, an IGMP membership report for

the group, or both.

PIMv2 Group Port The ports on which the Layer 2 Switch has received PIM SM join

messages for the group.

Source, Port list The IP address of each PIM SM source and the Layer 2 Switch ports

connected to the receivers of the source.

Refer to the

FastIron Command Reference

for information on PIM SM snooping commands.

Displaying PIM SM snooping information for a specific group or source group pair

To display PIM SM snooping information for a specific group, enter the following command at any level of the CLI.

device#show ip multicast pimsm-snooping 230.1.1.1

Show pimsm snooping group 230.1.1.1 in all vlans

vlan 10,has 2 caches.

1 (*230.1.1.1) has 1 pim join ports out of 1 OIF

1(age=120)

1 has 1 src:10.20.20.66(120)

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To display PIM SM snooping information for a specific (source, group) pair, enter the following command at any level of the CLI.

device#show ip multicast pimsm-snooping 230.2.2.2 20.20.20.66

Show pimsm snooping source 10.20.20.66, group 230.2.2.2 in all vlans

vlan 10:(*230.2.2.2) has 1 pim join ports out of 2 OIF

1(age=0)

1 has 1 src:10.20.20.66(0)

Syntax: show ip multicast pimsm-snooping

group-address

[

source-ip-address

]

The Brocade device determines which address is the group address and which one is the source address based on the ranges that the

address fall into. If the address is within the range of source addresses, then the router treats it as the source address. Likewise, if the

address falls in the range of group addresses, then the router assumes it is a group address.

The following table describes the information displayed by the show ip multicast pimsm-snooping command.

Field Description

vlan The VLAN membership ID of the source.

port The port on which the source is sending traffic. In this example, the port

number is 1.

age The age of the port, in seconds.

src The source address and age. The age (number of seconds) is indicated in

brackets immediately following the source.

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IPv6 Multicast Traffic Reduction

∙MLD snooping overview...............................................................................................................................................................................................43

∙MLD snooping configuration......................................................................................................................................................................................47

∙Displaying MLD snooping information................................................................................................................................................................ 54

∙Clearing MLD snooping counters and mcache...............................................................................................................................................59

∙Disabling the flooding of unregistered IPv6 multicast frames in an MLD-snooping-enabled VLAN............................60

∙PIM6 SM traffic snooping overview...................................................................................................................................................................... 60

∙PIM6 SM snooping configuration........................................................................................................................................................................... 63

∙PIM6 SM snooping show commands..................................................................................................................................................................64

MLD snooping overview

The default method a device uses to process an IPv6 multicast packet is to broadcast it to all ports except the incoming port of a VLAN.

Packets are flooded by hardware without going to the CPU, which may result in some clients receiving unwanted traffic.

If a VLAN is not Multicast Listening Discovery (MLD) snooping-enabled, it floods IPv6 multicast data and control packets to the entire

VLAN in hardware. When snooping is enabled, MLD packets are trapped to the CPU. Data packets are mirrored to the CPU and flooded

to the entire VLAN. The CPU then installs hardware resources so subsequent data packets can be hardware-switched to desired ports

without going through the CPU. If there is no client report, the hardware resource drops the data stream.

MLD protocols provide a way for clients and a device to exchange messages, and allow the device to build a database indicating which

port wants what traffic. Since the MLD protocols do not specify forwarding methods, MLD snooping or multicast protocols such as IPv6

PIM-Sparse Mode (PIM6 SM) are required to handle packet forwarding. PIM6 SM can route multicast packets within and outside a

VLAN, while MLD snooping can switch packets only within a VLAN.

MLD snooping provides multicast containment by forwarding traffic only to those clients that have MLD receivers for a specific multicast

group (destination address). The device maintains the MLD group membership information by processing MLD reports and generating

messages so traffic can be forwarded to ports receiving MLD reports. This is analogous to IGMP Snooping on Brocade Layer 3

switches.

An IPv6 multicast address is a destination address in the range of FF00::/8. A limited number of multicast addresses are reserved.

Because packets destined for the reserved addresses may require VLAN flooding, FSX devices do not snoop in the FF0X::00X range

(where X is from 00 to FF) and FFXX:XXXX:XXXX:XXXX:XXXX:XXXX:1:2. Data packets destined to these addresses are flooded to the

entire VLAN by hardware and mirrored to the CPU. Multicast data packets destined to addresses outside the FF0X::00X range and

FFXX:XXXX:XXXX:XXXX:XXXX:XXXX:1:2 are snooped. A client must send MLD reports in order to receive traffic.

An MLD device periodically sends general queries and sends group queries upon receiving a leave message, to ensure no other clients

at the same port still want this specific traffic before removing it. MLDv1 allows clients to specify which group (destination IPv6 address)

will receive traffic. (MLDv1 cannot choose the source of the traffic.) MLDv2 deals with source-specific multicasts, adding the capability

for clients to INCLUDE or EXCLUDE specific traffic sources. An MLDv2 device's port state can either be in INCLUDE or EXCLUDE

mode.

There are different types of group records for client reports. Clients respond to general queries by sending a membership report

containing one or more of the following records associated with a specific group:

∙Current-state record - Indicates the sources from which the client wants to receive or not receive traffic. This record contains

the addresses of the multicast sources and indicates whether or not traffic will be included (IS_IN) or excluded (IS_EX) from that

source address.

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∙Filter-mode-change record - If the client changes its current state from IS_IN to IS_EX, a TO_EX record is included in the

membership report. Likewise, if a client current state changes from IS_EX to IS_IN, a TO_IN record appears in the membership

report.

∙MLDv1 leave report - Equivalent to a TO_IN (empty) record in MLDv2. This record means that no traffic from this group will be

received, regardless of the source.

∙An MLDv1 group report - Equivalent to an IS_EX (empty) record in MLDv2. This record means that all traffic from this group

will be received, regardless of the source.

∙Source-list-change record - If the client wants to add or remove traffic sources from its membership report, the report can

include an ALLOW record, which contains a list of new sources from which the client wishes to receive traffic. The report can

also contain a BLOCK record, which lists current traffic sources from which the client wants to stop receiving traffic.

Support for MLD snooping and Layer 3 IPv6 multicast routing together on the same

device

The Brocade device supports global Layer 2 IPv6 multicast traffic reduction (MLD snooping) and Layer 3 IPv6 multicast routing (PIM-

Sparse) together on the same device in the full Layer 3 software image, as long as the Layer 2 feature configuration is at the VLAN level.

Forwarding mechanism in hardware

IP-based forwarding implementation on FCX and ICX devices

The following information about *,G or S,G fdb-based implementation is specific to FCX, ICX 6610, ICX 6430, ICX 6450, and ICX 6650

devices.

On both switch and router software images, MLD snooping is either *,G based or S,G based. The hardware can either match the group

address only (* G), or both the source and group (S, G) of the data stream. The hardware can match only the lowest 32 bits of a 128 bit

IPv6 address. This is 32-bit IP address matching, not 32-bit multicast MAC address 33-33-xx-xx-xx-xx matching.

If MLDv2 is configured in any port of a VLAN, the VLAN uses an (S, G) match, otherwise it uses (* G). Because the hardware can match

only the lowest 32 bits of a 128 bit IPv6 address, the output interfaces (OIF) of a hardware resource are the superset of the OIF of all

data streams sharing the same lowest 32 bits. For example, if groups ff10::1234:5678:abcd and ff20::5678:abcd share the same

hardware resource, then the OIF of the hardware matching (* 5678:abcd) is the superset of these two groups.

MAC-based forwarding implementation on FastIron X Series and the Brocade ICX 7750, ICX 7450,

and ICX 7250

Multicast Listening Discovery (MLD) snooping on Brocade devices is based on MAC address entries. When an IPv6 multicast data

packet is received, the packet destination MAC is matched with the MAC address entries in the IPv6 multicast table. If a match is found,

packets are sent to the ports associated with the MAC address. If a match is not found, packets are flooded to the VLAN and copied to

the CPU.

For IPv6 multicast, the destination MAC address is in the format 33-33-xx-yy-zz-kk, where xx-yy-zz-kk are the 32 lowest bits of the

IPv6 multicast group address. For example, the IPv6 group address 0xFF3E:40:2001:660:3007:123:0034:5678 maps to the IPv6

MAC address 33-33-00-34-56-78.

For two multicast traffic streams, Source_1 and Group1 (S1,G1) and Source_2 and Group2 (S2,G2), with the same or different source

addresses, if the lowest 32 bits of the 128-bit IPv6 group address are the same, they would map to the same destination MAC. Because

FSX devices support MAC-based forwarding for MLD snooping, the final multicast MAC address entry would be a superset of all the

IPv6 groups mapped to it. For example, consider the following three IPv6 multicast streams sent from port 5 of a Brocade device:

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∙(S1,G1) = (2060::5, ff1e::12), client port 1, port 2

∙(S2,G2) = (2060::6, ff1e:13::12), client port 2, port 3

∙(S3,G1) = (2060::7, ff1e::12), client port 4

Because the lowest 32 bits of the group address for G1 and G2 are the same, all three streams would use 33-33-00-00-00-12 as the

destination MAC address. MLD snooping would build a MAC entry with the MAC address 33-33-00-00-00-12 on egress ports 1, 2, 3,

and 4. As a result, all three streams would be sent to ports 1, 2, 3, and 4. Note that the above example assumes the following:

∙The Brocade device is running MLD snooping on VLAN 10 and all three streams are in VLAN 10

∙There are clients on port 1 and port 2 for (S1,G1)

∙There are clients on port 2 and port 3 for (S2,G2)

∙There are clients on port 4 for (S3,G1)

Hardware resources for MLD and PIMv6 SM snooping

Brocade devices allocate/program fdb/mac entries and application VLAN (vidx) to achieve multicast snooping in hardware. If a data

packet does not match any of these resources, it might be sent to the CPU, which increases the CPU burden. This can happen if the

device runs out of hardware resource, or is unable to install resources for a specific matching address due to hashing collision. The

hardware hashes addresses into available entries, with some addresses hashed into the same entry. If the collision number in an entry is

more than the hardware chain length, the resource cannot be installed.

MLD snooping configuration notes and feature limitations

∙Servers (traffic sources) are not required to send Multicast Listening Discovery (MLD) memberships.

∙The default MLD version is V1, where the source address is not sensitive. In this version, (S1,G1) and (S2,G1) would be

considered the same group as (*,G1).

∙If MLDv2 is configured on any port of a VLAN, you can check the source information, but because MLD snooping is MAC

based, (S,G) switching is not feasible.

∙Hardware resources are installed only when there is data traffic.

∙You can configure the maximum number of groups and the multicast cache (mcache) number.

∙The device supports static groups applying to specific ports. The device acts as a proxy to send MLD reports for the static

groups when receiving queries.

∙A user can configure static router ports, forcing all multicast traffic to be sent to these ports.

∙Brocade devices support fast leave for MLDv1, which stops traffic immediately to any port that has received a leave message.

∙Brocade devices support tracking and fast leave for MLDv2, which tracks all MLDv2 clients. If the only client on a port leaves,

traffic is stopped immediately.

∙An MLD device can be configured as a querier (active) or non-querier (passive). Queriers send queries. Non-queriers listen for

queries and forward them to the entire VLAN.

∙Every VLAN can be independently configured as a querier or a non-querier.

∙A VLAN that has a connection to an IPv6 PIM-enabled port on another router should be configured as a non-querier. When

multiple snooping devices connect together and there is no connection to IPv6 PIM ports, only one device should be

configured as the querier. If multiple devices are configured as active, only one will continue to send queries after the devices

have exchanged queries. Refer to the MLD snooping-enabled queriers and non-queriers section.

∙An MLD device can be configured to rate-limit the forwarding of MLDv1 membership reports to queriers.

∙Because an IPv6 link-local address as the source address when sending queries, a global address is not required.

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∙The MLD implementation allows snooping on some VLANs or on all VLANs. MLD can be enabled or disabled independently

for each VLAN. In addition, individual ports of a VLAN can be configured as MLDv1 and MLDv2. In general, global

configuration commands such as ipv6 multicast.... apply to all VLANs except those with a local multicast... configuration, which

supersedes the global configuration. Configuring the version on a port or a VLAN only affects the device sent query version.

The device always processes all versions of client reports regardless of the version configured.

∙MLD snooping requires hardware resources. If the device has insufficient resources, the data stream without a resource is

mirrored to the CPU in addition to being VLAN flooded, which can cause high CPU usage. To avoid this situation, Brocade

recommends that you avoid enabling snooping globally unless necessary.

∙To receive data traffic, MLD snooping requires clients to send membership reports. If a client does not send reports, you must

configure a static group to force traffic to client ports.

∙Multicast Router Discovery (MRD) messages are useful for determining which nodes attached to a switch have multicast

routing enabled. This capability is useful in a Layer 2 bridge domain with snooping switches. By utilizing MRD messages, Layer

2 switches can determine where to send multicast source data and group membership messages. Multicast source data and

group membership reports must be received by all multicast routers on a segment. Using the group membership protocol

Query messages to discover multicast routers is insufficient due to query suppression.

Because Brocade does not support MRD, this can lead to stream loss when non-Querier router ports age out on the Querier after the

initial Query election. To avoid such stream loss, configure a static router port on the querier on each interface that connects to a non-

querier snooping device.

The following details apply to the Brocade FSX 800 and FSX 1600 and to the Brocade ICX 7750, ICX 7450, and ICX 7250:

∙If MLDv2 is configured on any port of a VLAN, you can check the source information, but because MLD snooping is MAC-

based, (S,G) switching is not feasible.

∙High CPU utilization occurs when MLD Snooping and PIM6 routing are enabled simultaneously on FastIron X Series devices,

and if the ingressing VLAN of the snooping traffic has "router-interface" configuration. With this configuration, IPv6 Multicast

data packets received in the snooping VLANs are forwarded to client ports via the hardware; however, copies of these packets

are also received and dropped by the CPU.

MLD/PIMv6 SM snooping over Multi-Chasis Trunking is supported on the Brocade FSX 800 and FSX 1600, and the Brocade ICX

6650 and ICX 7750.

The following details apply to FCX, ICX 6610, ICX 6430, ICX 6450, and ICX 6650 devices:

∙If a VLAN is configured for MLDv2, the hardware matches (S G), otherwise it matches (* G).

∙When any port of a VLAN is configured for MLDv2, the VLAN matches both source and group (S, G) in hardware switching. If

no port is configured for MLDv2, the VLAN matches group only (* G). Matching (S, G) requires more hardware resources than (*

G) when there are multiple servers sharing the same group. For example, two data streams from different sources to the same

group require two (S, G) entries in MLDv2, compared to only one (* G) in MLD v1.

Use MLD v2 only in a source-specific application. Because each VLAN can be configured for the version independently, some VLANs

might match (* G) while others match (S G)

MLD snooping-enabled queriers and non-queriers

An MLD snooping-enabled device can be configured as a querier (active) or non-querier (passive). An MLD querier sends queries; a

non-querier listens for MLD queries and forwards them to the entire VLAN. When multiple MLD snooping devices are connected

together, and there is no connection to an IPv6 PIM-enabled port, one of the devices should be configured as a querier. If multiple

devices are configured as queriers, after multiple devices exchange queries, then all devices except the winner (the device with the lowest

address) stop sending queries. Although the system works when multiple devices are configured as queriers, Brocade recommends that

only one device, preferably the one with the traffic source, is configured as the querier.

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VLANs can also be independently configured as queriers or non-queriers. If a VLAN has a connection to an IPv6 PIM-enabled port on

another router, the VLAN should be configured as a non-querier.

Because non-queriers always forward multicast data traffic and MLD messages to router ports which receive MLD queries or IPv6 PIM

hellos, Brocade recommends that you configure the devices with the data traffic source (server) as queriers. If a server is attached to a

non-querier, the non-querier always forwards traffic to the querier regardless of whether or not there are clients on the querier.

NOTE

In a topology with one or more connected devices, at least one device must be running PIM, or configured as active. Otherwise,

no devices can send queries, and traffic cannot be forwarded to clients.

To configure the MLD mode (querier or non-querier) on an MLD snooping-enabled device, refer to Configuring the global MLD mode

on page 49. To configure the MLD mode on a VLAN, refer to Configuring the MLD mode for a VLAN on page 51.

MLD and VLAN configuration

You can configure MLD snooping on some VLANs or all VLANs. Each VLAN can be independently enabled or disabled for MLD

snooping, or can be configured with MLDv1 or MLDv2. In general, the IPv6 MLD snooping commands apply globally to all VLANs

except those configured with VLAN-specific MLD snooping commands. VLAN-specific MLD snooping commands supersede global

IPv6 MLD snooping commands.

MLDv1 with MLDv2

MLD snooping can be configured as MLDv1 or MLDv2 on individual ports on a VLAN. An interface or router sends queries and reports

that include the MLD version with which it has been configured. The version configuration applies only to the sending of queries. The

snooping device recognizes and processes MLDv1 and MLDv2 packets regardless of the version configured.

NOTE

To avoid version deadlock, when an interface receives a report with a lower version than that for which it has been configured,

the interface does not automatically downgrade the running MLD version.

MLD snooping configuration

Configuring Multicast Listening Discovery (MLD) snooping on an IPv6 device consists of the following global and VLAN-specific tasks.

MLD snooping global tasks

∙Configuring hardware and software resource limits

∙Disabling transmission and receipt of MLD packets on a port

∙Configuring the MLD mode: active or passive (must be enabled for MLD snooping)

∙Modifying the age interval

∙Modifying the interval for query messages (active MLD mode only)

∙Specifying the global MLD version

∙Enabling and disabling report control (rate limiting)

∙Modifying the leave wait time

∙Modifying the mcache age interval

∙Disabling error and warning messages

MLD snooping VLAN-specific tasks:

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∙Configuring the MLD mode for the VLAN: active or passive

∙Enabling or disabling MLD snooping for the VLAN

∙Configuring the MLD version for the VLAN

∙Configuring the MLD version for individual ports

∙Configuring static groups

∙Configuring static router ports

∙Disabling proxy activity for a static group

∙Enabling client tracking and the fast leave feature for MLDv2

∙Configuring fast leave for MLDv1

∙Configuring fast-convergence

Configuring the hardware and software resource limits

The system supports up to 8K of hardware-switched multicast streams. The following are the resource limits:

∙The default is 512 for most devices; for ICX 6430 devices the default is 256.

∙FCX, FSX, ICX 6610, ICX 6450 and ICX 6650 devices support up to 8192 MLD snooping mcache entries.

∙ICX 6430 devices support up to 2048 MLD snooping mcache entries.

∙ICX 7750 routers support 3072 MLD snooping mcache entries; ICX 7750 switches support 8192 MLD snooping mcache

entries.

∙In Release 8.0.10a and later releases, ICX 7750 routers support 6144 MLD snooping mcache entries; ICX 7750 switches

support 8192 MLD snooping mcache entries.

∙ICX 7250 and ICX 7450 devices support up to 8192 MLD snooping mcache entries.

To define the maximum number of MLD snooping mcache entries, enter the system-max mld-snoop-mcache

num

command.

Device(config)#system-max mld-snoop-mcache 8000

Syntax:[no] system-max mld-snoop-mcache

num

variable is a value from 256 to 8192. The default is 512.

The configured number is the upper limit of an expandable database. Client memberships exceeding the group limits are not processed.

∙FCX, FSX, ICX 6610, and ICX 6450 devices support up to 8192 MLD group addresses.

∙ICX 6430 devices support up to 4096 MLD group addresses.

∙ICX 6650 devices support 8192 MLD group addresses.

∙ICX 7750 switches support 8192 MLD group addresses.

∙ICX 7750 routers support 6K MLD group addresses.

∙ICX 7250 devices support 8192 MLD group addresses.

∙ICX 7450 devices support 8192 MLD group addresses.

To define the maximum number of multicast group addresses supported, enter the system-max mld-snoop-group-addr

num

command.

The default for MLD snooping group addresses is 4096 for most devices; on ICX 6430 devices the default is 1024.

Device(config)#system-max mld-snoop-group-addr 4000

Syntax:[no] system-max mld-snoop-group-addr

num

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For all devices except the ICX 6430, The

num

variable is a value from 256 to 8192. The default is 4096.

For the ICX 6430, the

num

variable is a value from 256 to 4096. The default is 1024.

Configuring the global MLD mode

You can configure a Brocade device for either active or passive (default) MLD mode. If you specify an MLD mode for a VLAN, the MLD

mode overrides the global setting.

∙Active - In active MLD mode, a device actively sends out MLD queries to identify IPv6 multicast groups on the network, and

makes entries in the MLD table based on the group membership reports it receives from the network.

∙Passive - In passive MLD mode, the device forwards reports to the router ports which receive queries. MLD snooping in

passive mode does not send queries, but does forward queries to the entire VLAN.

To globally set the MLD mode to active, enter the ipv6 multicast active command.

device(config)#ipv6 multicast active

Syntax: [no] ipv6 multicast [ active | passive ]

Omitting both the active and passive keywords is the same as entering ipv6 multicast passive .

NOTE

The ipv6 mld-snooping command is replaced by the ipv6 multicast command; the mld-snooping command is replaced by the

multicast6 command.

Modifying the age interval

When the device receives a group membership report, it makes an entry in the MLD group table for the group in the report. The age

interval specifies how long the entry can remain in the table without the device receiving another group membership report. When

multiple devices connect together, all devices should be configured with the same age interval. The age interval should be at least twice

that of the query interval, so that missing one report will not stop traffic. For a non-querier, the query interval should equal that of the

querier.

To modify the age interval, enter a command such as the following.

device(config)#ipv6 multicast age-interval 280

Syntax:[no] ipv6 multicast age-interval

interval

The interval parameter specifies the aging time. You can specify a value from 20 to 7200 seconds. The default is 260 seconds.

Modifying the query interval (active MLD snooping mode only)

If the MLD mode is set to active, you can modify the query interval, which specifies how often the Brocade device sends group

membership queries. By default, queries are sent every 60 seconds. When multiple queriers connect together, all queriers should be

configured with the same interval.

To modify the query interval, enter the ipv6 multicast query-interval

interval

command.

Device(config)#ipv6 multicast query-interval 120

Syntax: [no] ipv6 multicast query-interval

interval

The

interval

parameter specifies the interval between queries. You can specify a value from 10 to 3600 seconds. The default is 125

seconds.

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Configuring the global MLD version

The default version is MLDv1. You can specify the global MLD version on the device as either MLDv1 or MLDv2. For example, the

following command configures the device to use MLDv2.

device(config)#ipv6 multicast version 2

Syntax: [no] ipv6 multicast version {1 | 2}

You can also specify the MLD version for individual VLANs, or individual ports within VLANs. If no MLD version is specified for a VLAN,

then the globally configured MLD version is used. If an MLD version is specified for individual ports in a VLAN, those ports use that

version instead of the version specified for the VLAN or the globally specified version. The default is MLDv1.

Configuring report control

When a device is in passive mode, it forwards reports and leave messages from clients to the upstream router ports that are receiving

queries.

You can configure report control to rate-limit report forwarding for the same group to no more than once per 10 seconds. This rate

limiting does not apply to the first report answering a group-specific query.

NOTE

This feature applies to MLDv1 only. The leave messages are not rate limited.

MLDv1 membership reports for the same group from different clients are considered to be the same, and are rate-limited. This alleviates

the report storm caused by multiple clients answering the upstream router query.

To enable report-control, enter the ipv6 multicast report-control command.

device(config)#ipv6 multicast report-control

Syntax: [no] ipv6 multicast report-control

Modifying the wait time before stopping traffic when receiving a leave message

You can define the wait time before stopping traffic to a port when the device receives a leave message for that port. The device sends

group-specific queries once per second to determine if any client on the same port still needs the group.

Device(config)#ipv6 multicast leave-wait-time 1

Syntax: [no] ipv6 multicast leave-wait-time

num

The

num

variable is a value from 1 to 5. The default is 2. Because of the internal timer accuracy, the actual wait time is between n and (n

+1) seconds, where n is the configured value.

Modifying the multicast cache aging time

You can set the time for a multicast cache (mcache) to age out when it does not receive traffic. Two seconds before an mcache is aged

out, the device mirrors a packet of the mcache to the CPU to reset the age. If no data traffic arrives within two seconds, the mcache is

deleted.

Note that in devices like the Brocade FSX 800 and FSX 1600 and to the Brocade ICX 7750, ICX 7450, and ICX 7250 where MAC-

based MLD snooping is supported, more than one mcache can be mapped to the same destination MAC. Hence, when an mcache

entry is deleted, the MAC entry may not be deleted. If you configure a lower value, the resource consumed by idle streams is quickly

removed, but packets are mirrored to the CPU more frequently. Configure a higher value only when data streams are arriving

consistently.

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You can use the show ipv6 multicast mcache command to view the currently configured mcache age. Refer to the “Enabling or disabling

PIM6 SM snooping” section.

To modify the multicast cache age out time, enter the ipv6 multicast mcache-age command.

Device(config)#ipv6 multicast mcache-age 180

Syntax: [no] ipv6 multicast mcache-age

num

The

num

variable is a value from 60 to 3600 seconds, and the default is 60 seconds.

Disabling error and warning messages

Error or warning messages are printed when the device runs out of software resources or when it receives packets with the wrong

checksum or groups. These messages are rate limited. You can turn off these messages by entering the ipv6 multicast verbose-off

command.

device(config)#ipv6 multicast verbose-off

Syntax: [no] ipv6 multicast verbose-off

Configuring the MLD mode for a VLAN

You can configure a VLAN for either the active or passive (default) MLD mode. The VLAN setting overrides the global setting:

∙Active - In active MLD mode, the device actively sends out MLD queries to identify IPv6 multicast groups on the network, and

makes entries in the MLD table based on the group membership reports it receives from the network.

∙Passive - In passive MLD mode, the device forwards reports to router ports that receive queries. MLD snooping in the passive

mode does not send queries. However, it does forward queries to the entire VLAN.

To set the MLD mode for VLAN 20 to active, enter the following commands.

device(config)#vlan 20

device(config-vlan-20)#multicst6 active

Syntax: [no] multicast6 [active | passive]

The default mode is passive.

Disabling MLD snooping for the VLAN

When MLD snooping is enabled globally, you can disable it for a specific VLAN. For example, the following commands disable MLD

snooping for VLAN 20. This setting overrides the global setting for VLAN 20.

device(config)#vlan 20

device(config-vlan-20)#multicast6 disable-mld-snoop

Syntax: [no] multicast6 disable-mld-snoop

Configuring the MLD version for the VLAN

You can specify the MLD version for a VLAN. For example, the following commands configure VLAN 20 to use MLDv2.

device(config)#vlan 20

device(config-vlan-20)#multicast6 version 2

Syntax: [no] multicast6 version [1 | 2]

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When no MLD version is specified, the globally-configured MLD version is used. If an MLD version is specified for individual ports,

these ports use that version, instead of the version specified for the VLAN.

Configuring the MLD version for individual ports

You can specify the MLD version for individual ports in a VLAN. For example, the following commands configure ports 1/1/4, 1/1/5, 1/1/6

and 1/2/1 to use MLDv2. The other ports use the MLD version specified with the multicast6 version command, or the globally

configured MLD version.

Device(config)#vlan 20

Device(config-vlan-20)#multicast6 port-version 2 ethernet 1/2/1 ethernet 1/1/4 to 1/1/6

Syntax: [no] multicast6 port-version [1 | 2 ] ethernet

unit/slot/port

Configuring static groups

A snooping-enabled VLAN cannot forward multicast traffic to ports that do not receive MLD membership reports. To allow clients to

send reports, you can configure a static group that applies to individual ports on the VLAN. You cannot configure a static group that

applies to the entire VLAN.

The maximum number of supported static groups in a VLAN is 512, and the maximum number of supported static groups for individual

ports in a VLAN is 256. The static group forwards packets to the static group ports even if they have no client membership reports.

Configure a static group for specific ports on VLAN 20 using commands similar to the following.

device(config)#vlan 20

device(config-vlan-20)#multicast6 static-group ff05::100 count 2 ethe 1/1/3 ethe 1/1/5 to 1/1/7

Syntax: [no] multicast6 static-group

ipv6-address

[ count

num

] [

unit/slot/port

]

The

ipv6-address

parameter is the IPv6 address of the multicast group.

The count is optional, which allows a contiguous range of groups. Omitting the count

num

is equivalent to the count being 1.

Configuring static router ports

All multicast control and data packets are forwarded to router ports that receive queries. Although router ports are learned, you can

configure static router ports to force multicast traffic to specific ports, even though these ports never receive queries. To configure static

router ports, enter commands such as the following:

Device(config)#vlan 70

Device(config-vlan-70)#multicast6 router-port ethernet 1/1/4 to 1/1/5 ethernet 1/1/8

Syntax: [no] multicast6 router-port ethernet

unit/slot/port

Disabling static group proxy

A device with statically configured groups acts as a proxy and sends membership reports for its static groups when it receives general or

group-specific queries. When a static group configuration is removed, the group is immediately deleted from the active group table.

However, the device does not send leave messages to the querier. The querier should age out the group. The proxy activity can be

disabled (the default is enabled).

device(config)#vlan 20

device(config-vlan-20)#multicast6 proxy-off

Syntax: [no] multicast6 proxy-off

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By default, MLD snooping proxy is enabled.

Enabling MLDv2 membership tracking and fast leave for the VLAN

MLDv2 provides membership tracking and fast leave services to clients. In MLDv1, only one client per interface must respond to a router

queries; leaving some clients invisible to the router, which makes it impossible for the device to track the membership of all clients in a

group. In addition, when a client leaves the group, the device sends group-specific queries to the interface to see if other clients on that

interface need the data stream of the client who is leaving. If no client responds, the device waits a few seconds before stopping the

traffic. You can configure the wait time with the ipv6 multicast6 leave-wait-time command. See Enabling or disabling PIM6 SM

snooping for more information.

MLDv2 requires that every client respond to queries, allowing the device to track every client. When the tracking feature is enabled, the

device immediately stops forwarding traffic to the interface if an MLDv2 client sends a leave message, and there is no other client. This

feature requires the entire VLAN to be configured for MLDv2 and have no MLDv1 clients. If a client does not send a report during the

specified group membership time (the default is 140 seconds), that client is removed from the tracking list.

Every group on a physical port keeps its own tracking record. However, it can track group membership only; it cannot track by (source,

group). For example, Client A and Client B belong to group1 but each is receiving traffic from different sources. Client A receives a traffic

stream from (source_1, group1) and Client B receives a traffic stream from (source_2, group1). The device waits for the configured

leave-

wait-time

before it stops the traffic because the two clients are in the same group. If the clients are in different groups, the waiting period

is ignored and traffic is stopped immediately.

To enable tracking and fast leave for VLAN 20, enter the following commands.

device(config)#vlan 20

device(config-vlan-20)#multicast6 tracking

Syntax: [no] multicast6 tracking

The membership tracking and fast leave features are supported for MLDv2 only. If a port or client is not configured for MLDv2, the

multicast6 tracking command is ignored.

Configuring fast leave for MLDv1

When a device receives an MLDv1 leave message, it sends out multiple group-specific queries. If no other client replies within the waiting

period, the device stops forwarding traffic to this port. Configuring fast-leave-v1 allows the device to stop forwarding traffic to a port

immediately upon receiving a leave message. The device does not send group-specific queries. When fast-leave-v1 is configured on a

VLAN, make sure you do not have multiple clients on any port that is part of the VLAN. In a scenario where two devices connect, the

querier device should not be configured for fast-leave-v1, because the port might have multiple clients through the non-querier. The

number of queries and the waiting period (in seconds) can be configured using the ipv6 multicast leave-wait-time command. See

Enabling or disabling PIM6 SM snooping for more information.

To configure fast leave for MLDv1, use commands such as the following.

device(config)#vlan 20

device(config-vlan-20)#multicast6 fast-leave-v1

Syntax: [no] multicast6 fast-leave-v1

Enabling fast convergence

In addition to periodically sending general queries, an active (querier) device sends out general queries when it detects a new port.

However, since it does not recognize the other device port-up event, the multicast traffic might still use the query-interval time to resume

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after a topology change. Configuring fast-convergence allows the device to listen to topology change events in Layer 2 protocols, such

as spanning tree, and send general queries to shorten the convergence time.

If the Layer 2 protocol is unable to detect a topology change, the fast-convergence feature may not work. For example, if the direct

connection between two devices switches from one interface to another, the rapid spanning tree protocol (802.1w) considers this an

optimization action, rather than a topology change. In this case, other devices will not receive topology change notifications and will be

unable to send queries to speed up the convergence. The original spanning tree protocol does not recognize optimization actions, and

fast-convergence works in all cases.

To enable fast-convergence, enter commands such as the following.

device(config)#vlan 70

device(config-vlan-70)#multicast6 fast-convergence

Syntax: [no] multicast6 fast-convergence

Displaying MLD snooping information

You can display the following MLD snooping information:

∙MLD snooping error information

∙Group and forwarding information for VLANs

∙Information about MLD snooping mcache

∙MLD memory pool usage

∙Status of MLD traffic

∙MLD information by VLAN

Displaying MLD snooping error information

To display information about possible MLD errors, enter the following command.

device#show ipv6 multicast error

snoop SW processed pkt: 173, up-time 160 sec

Syntax: show ipv6 multicast error

The following table describes the output from the show ipv6 multicast error command.

Field Description

SW processed pkt The number of IPv6 multicast packets processed by MLD snooping.

up-time The MLD snooping up time.

Displaying MLD group information

To display default, maximum, current, and configured values for system maximum parameters, use the show default values command.

The following output example does not show complete output; it shows only MLD group values.

Device(config)#show default values

System Parameters Default Maximum Current Configured

MLD-snoop-group-addr 4096 8192 5000 5000

To display MLD group information, enter the show ipv6 multicast group command.

Device#show ipv6 multicast group

p-:physical, ST:static, QR:querier, EX:exclude, IN:include, Y:yes, N:no

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VL1 : 263 grp, 263 grp-port, tracking_enabled

group p-port ST QR life mode source

1 ff0e::ef00:a0e3 1/1/7 N Y 120 EX 0

2 ff01::1:f123:f567 1/1/9 N Y IN 1

NOTE

In this example, an MLDv1 group is in EXCLUDE mode with a source of 0. The group excludes traffic from the 0 (zero) source

list, which actually means that all traffic sources are included.

To display detailed MLD group information, enter the following command.

Device#show ipv6 multicast group ff0e::ef00:a096 detail

Display group ff0e::ef00:a096 in all interfaces in details.

p-:physical, ST:static, QR:querier, EX:exclude, IN:include, Y:yes, N:no

VL1 : 1 grp, 1 grp-port, tracking_enabled

group p-port ST QR life mode source

1 ff0e::ef00:a096 1/1/7 N Y 100 EX 0

group: ff0e::ef00:a096, EX, permit 0 (source, life):

life=100, deny 0:

If tracking and fast leave are enabled, you can display the list of clients for a particular group by entering the following command.

Device#show ipv6 multicast group ff0e::ef00:a096 tracking

Display group ff0e::ef00:a096 in all interfaces with tracking enabled.

p-:physical, ST:static, QR:querier, EX:exclude, IN:include, Y:yes, N:no

VL1 : 1 grp, 1 grp-port, tracking_enabled

group p-port ST QR life mode source

1 ff0e::ef00:a096 1/1/7 N Y 80 EX 0

receive reports from 1 clients: (age)

(2001:DB8::1011:1213:1415 60)

Syntax: show ipv6 multicast group [

group-address

[ detail ] [ tracking ] ]

To receive a report for a specific multicast group, enter that group address for

group-address

Enter the detail keyword to display the source list of a specific VLAN.

Enter the tracking keyword for information on interfaces that are tracking-enabled.

The following table describes the information displayed by the show ipv6 multicast group command.

Field Description

group The address of the IPv6 group (destination IPv6 address).

p-port The physical port on which the group membership was received.

ST Yes indicates that the MLD group was configured as a static group; No

means it was learned from reports.

QR Yes means the port is a querier port; No means it is not. A port becomes a

non-querier port when it receives a query from a source with a lower

source IP address than the port.

life The number of seconds the group can remain in EXCLUDE mode. An

EXCLUDE mode changes to INCLUDE if it does not receive an IS_EX or

TO_EX message during a specified period of time. The default is 140

seconds. There is no life displayed in INCLUDE mode.

mode The current mode of the interface: INCLUDE or EXCLUDE. If the

interface is in INCLUDE mode, it admits traffic only from the source list. If

the interface is in EXCLUDE mode, it denies traffic from the source list

and accepts the rest.

source Identifies the source list that will be included or excluded on the interface.

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Field Description

An MLDv1 group is in EXCLUDE mode with a source of 0. The group

excludes traffic from 0 (zero) source list, which actually means that all

traffic sources are included.

group If you requested a

detailed

report, the following information is displayed:

∙The multicast group address

∙The mode of the group

∙Sources from which traffic will be admitted (INCLUDE) or

denied (EXCLUDE) on the interface.

∙The life of each source list.

If you requested a

tracking/fast leave

report, the clients from which reports

were received are identified.

Displaying MLD snooping mcache information

To display default, maximum, current, and configured values for system maximum parameters, use the show default values command.

The following output example does not show complete output; it shows only MLD mcache values.

device(config)#show default values

System Parameters Default Maximum Current Configured

mld-snoop-mcache 512 8192 512 512

The MLD snooping mcache contains multicast forwarding information for VLANs. To display information in the multicast forwarding

mcache, enter the show ipv6 multicast mcache command.

device#show ipv6 multicast mcache

Example: (S G) cnt=: (S G) are the lowest 32 bits, cnt: SW proc. count

OIF: 1/1/22 TR(1/1/32,1/1/33), TR is trunk, 1/1/32 primary, 1/1/33 output

vlan 1, has 2 cache

1 (abcd:ef50 0:100), cnt=121

OIF: 1/1/11 1/1/9

age=0s up-time=120s vidx=4130 (ref-cnt=1)

2 (abcd:ef50 0:101), cnt=0

OIF: entire vlan

age=0s up-time=0s vidx=8191 (ref-cnt=1)

vlan 70, has 0 cache

Syntax: show ipv6 multicast mcache

The following table describes the output from the show ipv6 multicast mcache command. Displaying software resource usage for

VLANs

Field Description

(abcd:ef50 0:100): The lowest 32 bits of source and group. It is displayed in XXXX:XXXX hex

format. Here XXXX is a 16-bit hex number.

cnt The number of packets processed in software.

OIF Output interfaces.

age The mcache age in seconds. The mcache is reset to 0 if traffic continues

to arrive, otherwise it is aged out when it reaches the time defined by ipv6

multicast mcache-age.

uptime The up time of this mcache in seconds.

vidx The vidx is shared among mcaches using the same output interfaces. The

vidx specifies the output port list, which shows the index. Valid range is

from 4096 to 8191.

ref-cnt The number of mcaches using this vidx.

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To display information about the software resources used, enter the following command.

device#show ipv6 multicast resource

alloc in-use avail get-fail limit get-mem size init

mld group 512 9 503 0 32000 272 28 256

mld phy port 1024 16 1008 0 200000 279 21 1024

snoop group hash 512 9 503 0 59392 272 20 256

.... Entries deleted

total pool memory 194432 bytes

has total 1 forwarding hash

Available vidx: 4061

Syntax: show ipv6 multicast resource

The following table describes the output from the show ipv6 multicast resource command.

Field Displays

alloc The allocated number of units.

in-use The number of units which are currently used.

avail The number of available units.

get-fail The number of resource failures

NOTE

It is important to pay close attention to this field.

limit The upper limit of this expandable field. The MLD group limit is

configured using the system-max mld-snoop-group-addr command. The

snoop mcache entry limit is configured using the system-max mld-

snoop-mcache command.

get-mem The current memory allocation. This number should continue to increase.

size The size of a unit (in bytes).

init The initial allocated amount of memory.

NOTE

This number can be increased. (More memory can be

allocated if necessary.)

Available vidx The output interface (OIF) port mask used by mcache. The entire device

has a maximum of 4096 vidx. Different mcaches with the same OIF

share the same vidx. If vidx is not available, the stream cannot be

hardware-switched.

Displaying status of MLD snooping traffic

To display status information for MLD snooping traffic, enter the show ipv6 multicast traffic command.

device#show ipv6 multicast traffic

MLD snooping: Total Recv: 32208, Xmit: 166

Q: query, Qry: general Q, G-Qry: group Q, GSQry: group-source Q, Mbr: member

Recv QryV1 QryV2 G-Qry GSQry MbrV1 MbrV2 Leave

VL1 0 0 0 0 31744 208 256

VL70 0 0 0 0 0 0 0

Recv IsIN IsEX ToIN ToEX ALLOW BLOCK Pkt-Err

VL1 1473 31784 0 1 1 7 0

VL70 0 0 0 0 0 0 0

Send QryV1 QryV2 G-Qry GSQry MbrV1 MbrV2

VL1 0 0 166 0 0 0

VL70 0 0 0 0 0 0

Syntax: show ipv6 multicast traffic

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The following table describes the information displayed by the show ipv6 multicast traffic command.

Field Description

Q Query

Qry General Query

QryV1 Number of general MLDv1 queries received or sent.

QryV2 Number of general MLDv2 snooping queries received or sent.

G-Qry Number of group specific queries received or sent.

GSQry Number of group source specific queries received or sent.

MBR The membership report.

MbrV1 The MLDv1 membership report.

MbrV2 The MLDv2 membership report.

IsIN Number of source addresses that were included in the traffic.

IsEX Number of source addresses that were excluded in the traffic.

ToIN Number of times the interface mode changed from EXCLUDE to

INCLUDE.

ToEX Number of times the interface mode changed from INCLUDE to

EXCLUDE.

ALLO Number of times additional source addresses were allowed on the

interface.

BLK Number of times sources were removed from an interface.

Pkt-Err Number of packets having errors such as checksum errors.

Displaying MLD snooping information by VLAN

You can display MLD snooping information for all VLANs or for a specific VLAN. For example, to display MLD snooping information for

VLAN 70, enter the show ipv6 multicast vlan command.

device#show ipv6 multicast vlan 70

version=1, query-t=60, group-aging-t=140, max-resp-t=3, other-qr-present-t=123

VL70: cfg V2, vlan cfg passive, 2 grp, 0 (SG) cache, rtr ports,

router ports: 1/1/36(120) 2001:DB8::2e0:52ff:fe00:9900,

1/1/26 has 2 grp, non-QR (passive), cfg V1

group: ff10:1234::5679, life = 100

group: ff10:1234::5678, life = 100

1/1/35 has 0 grp, non-QR (QR=2001:DB8::2e0:52ff:fe00:9900, age=20), dft V2 trunk

Syntax: show ipv6 multicast vlan [

vlan-id

]

If you do not specify the

vlan-id

variable, information for all VLANs is displayed.

The following table describes information displayed by the show ipv6 multicast vlan command.

Field Description

version The MLD version number.

query-t How often a querier sends a general query on the interface.

group-aging-t Number of seconds membership groups can be members of this group

before aging out.

rtr-port The router ports which are the ports receiving queries. The display

router ports: 1/1/36(120) 2001:DB8::2e0:52ff:fe00:9900

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Field Description

means port 1/1/36 has a querier with 2001:DB8::2e0:52ff:fe00:9900 as

the link-local address, and the remaining life is 120 seconds.

max-resp-t The maximum number of seconds a client can wait before it replies to the

query.

non-QR Indicates that the port is a non-querier.

QR Indicates that the port is a querier.

Clearing MLD snooping counters and mcache

The clear commands for MLD snooping should only be used in troubleshooting situations or when recovering from error conditions.

Clearing MLD counters on all VLANs

To clear MLD snooping error and traffic counters on all VLANs, enter the clear ipv6 multicast counters command.

device#clear ipv6 multicast counters

Syntax: clear ipv6 multicast counters

Clearing the mcache on all VLANs

To clear the mcache on all VLANs, enter the clear ipv6 multicast mcache command.

device#clear ipv6 multicast mcache

Syntax: clear ipv6 multicast mcache

Clearing the mcache on a specific VLAN

To clear the mcache on a specific VLAN, enter the clear ipv6 multicast vlan mcache command.

device#clear ipv6 multicast vlan 10 mcache

Syntax: clear ipv6 multicast vlan

vlan-id

mcache

The

vlan-id

parameter specifies the specific VLAN from which to clear the cache.

Clearing traffic counters on a specific VLAN

To clear the traffic counters on a specific VLAN, enter the clear ipv6 multicast vlan traffic command.

device#clear ipv6 multicast vlan 10 traffic

Syntax: clear ipv6 multicast vlan

vlan-id

traffic

The

vlan-id

parameter specifies the specific VLAN from which to clear the traffic counters.

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Disabling the flooding of unregistered IPv6 multicast frames in an MLD-

snooping-enabled VLAN

NOTE

Disabling the flooding of unregistered IPv6 multicast frames in an MLD-snooping-enabled VLAN is supported only on the

following platforms:

∙The Brocade ICX 6650

∙The Brocade ICX 7750 (standalone and stacking)

Support for this feature on the Brocade ICX 7750 was introduced in FastIron 8.0.10d. In releases prior to FastIron 8.0.30,

support for this feature on the Brocade ICX 7750 was for devices in standalone mode only.

To disable the flooding of unregistered IPv6 multicast frames in an MLD-snooping-enabled VLAN, use the ipv6 multicast disable-

flooding command in global configuration mode.

The following example disables flooding of unregistered IPv6 multicast frames.

Device(config)# ipv6 multicast disable-flooding

PIM6 SM traffic snooping overview

When multiple PIM sparse routers connect through a snooping-enabled device, the Brocade device always forwards multicast traffic to

these routers. For example, PIM sparse routers R1, R2, and R3 connect through a device. Assume R2 needs traffic, and R1 sends it to the

device, which forwards it to both R2 and R3, even though R3 does not need it. A PIM6 SM snooping-enabled device listens to join and

prune messages exchanged by PIM sparse routers, and stops traffic to the router that sends prune messages. This allows the device to

forward the data stream to R2 only.

PIM6 SM traffic snooping requires MLD snooping to be enabled on the device. MLD snooping configures the device to listen for MLD

messages. PIM6 SM traffic snooping provides a finer level of multicast traffic control by configuring the device to listen specifically for

PIM6 SM join and prune messages sent from one PIM6 SM router to another through the device.

Application examples of PIM6 SM traffic snooping

Figure 2 shows an example application of the PIM6 SM traffic snooping feature. In this example, a device is connected through an IP

router to a PIM6 SM group source that is sending traffic for two PIM6 SM groups. The device also is connected to a receiver for each of

the groups.

When PIM6 SM traffic snooping is enabled, the device starts listening for PIM6 SM join and prune messages and MLD group

membership reports. Until the device receives a PIM6 SM join message or an MLD group membership report, the device forwards IP

multicast traffic out all ports. Once the device receives a join message or group membership report for a group, the device forwards

subsequent traffic for that group only on the ports from which the join messages or MLD reports were received.

In this example, the router connected to the receiver for group ff1e::1:2 sends a join message toward the group source. Because PIM6

SM traffic snooping is enabled on the device, the device examines the join message to learn the group ID, then makes a forwarding entry

for the group ID and the port connected to the receiver router. The next time the device receives traffic for ff1e::1:2 from the group source,

the device forwards the traffic only on port 5/1, because that is the only port connected to a receiver for the group.

Notice that the receiver for group ff1e::3:4 is directly connected to the device. As a result, the device does not see a join message on

behalf of the client. However, because MLD snooping also is enabled, the device uses the MLD group membership report from the

client to select the port for forwarding traffic to group ff1e::3:4 receivers.

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The MLD snooping feature and the PIM6 SM traffic snooping feature together build a list of groups and forwarding ports for the VLAN.

The list includes PIM6 SM groups learned through join messages as well as MAC addresses learned through MLD group membership

reports. In this case, even though the device never sees a join message for the receiver for group ff1e::3:4, the device nonetheless learns

about the receiver and forwards group traffic to the receiver.

The device stops forwarding IP multicast traffic on a port for a group if the port receives a prune message for the group.

Notice that the ports connected to the source and the receivers are all in the same port-based VLAN on the device. This is required for

the PIM6 SM snooping feature. The devices on the edge of the Global Ethernet cloud are configured for MLD snooping and PIM6 SM

traffic snooping. Although this application uses multiple devices, the feature has the same requirements and works the same way as it

does on a single device.

The following figure shows another example application for PIM6 SM traffic snooping. This example shows devices on the edge of a

Global Ethernet cloud (a Layer 2 Packet over SONET cloud). Assume that each device is attached to numerous other devices such as

other Layer 2 Switches and Layer 3 Switches (routers).

NOTE

This example assumes that the devices are actually Brocade devices running Layer 2 Switch software.

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FIGURE 2 PIM6 SM traffic reduction in Global Ethernet environment

The devices on the edge of the Global Ethernet cloud are configured for MLD snooping and PIM6 SM traffic snooping. Although this

application uses multiple devices, the feature has the same requirements and works the same way as it does on a single device.

Configuration notes and limitations for PIM6 SM snooping

∙PIM6 SM snooping applies only to PIM6 SM version 2 (PIM6 SM V2).

∙PIM6 SM traffic snooping is supported in the Layer 2, base Layer 3, and full Layer 3 code.

∙MLD snooping must be enabled on the device that will be running PIM6 SM snooping. The PIM6 SM traffic snooping feature

requires MLD snooping.

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NOTE

Use the passive mode of MLD snooping instead of the active mode. The passive mode assumes that a router is sending group

membership queries as well as join and prune messages on behalf of receivers. The active mode configures the device to send

group membership queries.

∙All the device ports connected to the source and receivers or routers must be in the same port-based VLAN.

∙The PIM6 SM snooping feature assumes that the group source and the device are in different subnets and communicate

through a router. The source must be in a different IP subnet than the receivers. A PIM6 SM router sends PIM join and prune

messages on behalf of a multicast group receiver only when the router and the source are in different subnet. When the

receiver and source are in the same subnet, they do not need the router in order to find one another. They find one another

directly within the subnet.

The device forwards all IP multicast traffic by default. Once you enable MLD snooping and PIM6 SM traffic snooping, the device initially

blocks all PIM6 SM traffic instead of forwarding it. The device forwards PIM6 SM traffic to a receiver only when the device receives a

join message from the receiver. Consequently, if the source and the downstream router are in the same subnet, and PIM6 SM traffic

snooping is enabled, the device blocks the PIM6 SM traffic and never starts forwarding the traffic. This is because the device never

receives a join message from the downstream router for the group. The downstream router and group find each other without a join

message because they are in the same subnet.

NOTE

If the "route-only" feature is enabled on a Layer 3 Switch, PIM6 SM traffic snooping will not be supported.

PIM6 SM snooping configuration

Configuring PIM6 SM snooping on a Brocade device consists of the following global and VLAN-specific tasks.

Perform the following global PIM6 SM snooping task:

∙Enabling or disabling PIM6 SM snooping

Perform the following VLAN-specific PIM6 SM snooping tasks:

∙Enabling PIM6 SM snooping on a VLAN

∙Disabling PIM6 SM snooping on a VLAN

Enabling or disabling PIM6 SM snooping

Use PIM6 SM snooping only in topologies where multiple PIM sparse routers connect through a device. PIM6 SM snooping does not

work on a PIM dense mode router which does not send join messages and traffic to PIM dense ports is stopped. A PIM6 SM snooping-

enabled device displays a warning if it receives PIM dense join or prune messages.

Perform the following steps to enable PIM6 SM snooping globally.

1. Enable MLD snooping passive globally.

device(config)#ipv6 multicast passive

2. Enable PIM6 SM snooping globally.

device(config)#ipv6 pimsm-snooping

This command enables PIM6 SM traffic snooping. The PIM6 SM traffic snooping feature assumes that the network has routers

that are running PIM6 SM.

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To disable PIM6 SM snooping, enter the no ipv6 pimsm-snooping command.

device(config)#no ipv6 pimsm-snooping

If you also want to disable IP multicast traffic reduction, enter the no ipv6 multicast command.

device(config)#no ipv6 multicast

Syntax: [no] ipv6 pimsm-snooping

Enabling PIM6 SM snooping on a VLAN

Perform the following steps to enable PIM6 SM snooping on a VLAN.

1. Configure a VLAN and add the ports that are connected to the device and host in the same port-based VLAN.

device(config)#vlan 20

device(config-vlan-20)#untagged etherenet 1/1/5 ethernet 1/1/7 ethernet 1/1/11

2. Enable MLD snooping passive on the VLAN.

device(config-vlan-20)#multicast6 passive

3. Enable PIM6 SM snooping on the VLAN.

device(config-vlan-20)#multicast6 pimsm-snooping

Syntax: [no] multicast6 pimsm-snooping

Disabling PIM6 SM snooping on a VLAN

When PIM6 SM snooping is enabled globally, you can still disable it for a specific VLAN. For example, the following commands disable

PIM6 SM snooping for VLAN 20. This setting overrides the global setting.

device(config)#vlan 20

device(config-vlan-20)#multicast6 disable-pimsm-snoop

Syntax: [no] multicast6 disable-pimsm-snoop

PIM6 SM snooping show commands

This section shows how to display information about PIM6 SM snooping.

Displaying PIM6 SM snooping information

To display PIM6 SM snooping information, enter the show ipv6 multicast pimsm-snooping command.

Device#show ipv6 multicast pimsm-snooping

Example: Port: 7/3 (ref_count=1)

ref_count: no of entries in pimsm snoop cache added this oif)

vlan 503, has 1 caches.

1 (* 2:3) has 1 pim join ports out of 1 OIF

1/1/4 (ref_count=2),

Refer to the

FastIron Command Reference

for more information on PIM SM commands.

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Displaying PIM6 SM snooping for a VLAN

You can display PIM6 SM snooping information for all groups by entering the following command at any level of the CLI on a Layer 2

switch.

Device#show ipv6 multicast pimsm-snooping vlan 25

vlan 25, has 2 caches.

1 (0:11 1:3) has 2 pim join ports out of 2 OIF

1/1/2 (age=30), 2/1/3 (age=30),

1/1/2 has 1 src: 15::11(30),

2/1/3 has 1 src: 15::11(30),

2 (0:16 1:3) has 2 pim join ports out of 2 OIF

2/1/3 (age=90), 1/1/2 (age=10),

1/1/2 has 1 src: 15::16(10),

Syntax: show ipv6 multicast pimsm-snooping vlan

vlan-id

Enter the ID of the VLAN for the

vlan-id

parameter.

The following table describes the information displayed by the show ipv6 multicast pimsm-snooping command.

Field Description

VLAN ID The port-based VLAN to which the following information applies and the

number of members in the VLAN.

PIM6 SM Neighbor list The PIM6 SM routers that are attached to the Layer 2 Switch ports.

The value following "expires" indicates how many seconds the Layer 2

Switch will wait for a hello message from the neighbor before determining

that the neighbor is no longer present and removing the neighbor from

the list.

Multicast Group The IP address of the multicast group.

NOTE

The fid and camindex values are used by Brocade Technical

Support for troubleshooting.

Forwarding Port The ports attached to the group receivers. A port is listed here when it

receives a join message for the group, an MLD membership report for the

group, or both.

PIMv2 Group Port The ports on which the Layer 2 Switch has received PIM6 SM join

messages for the group.

Source, Port list The IP address of each PIM6 SM source and the Layer 2 Switch ports

connected to the receivers of the source.

Refer to the

FastIron Command Reference

for more information on PIM SM commands.

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IPv4 Multicast Protocols

∙Overview of IP multicasting.........................................................................................................................................................................................67

∙Support for Multicast Multi-VRF..............................................................................................................................................................................68

∙Changing global IP multicast parameters...........................................................................................................................................................68

∙Adding an interface to a multicast group...............................................................................................................................................................71

∙Multicast non-stop routing...........................................................................................................................................................................................72

∙Passive multicast route insertion .............................................................................................................................................................................74

∙IP multicast boundaries..................................................................................................................................................................................................75

∙PIM Dense ............................................................................................................................................................................................................................ 77

∙PIM convergence on MAC movement................................................................................................................................................................ 89

∙PIM Sparse ..........................................................................................................................................................................................................................89

∙PIM convergence on MAC movement (PIM sparse mode).....................................................................................................................96

∙IP multicast PIM neighbor filter.................................................................................................................................................................................96

∙PIM Passive.......................................................................................................................................................................................................................... 97

∙Multicast Outgoing Interface (OIF) list optimization......................................................................................................................................98

∙Displaying system values.............................................................................................................................................................................................98

∙Displaying PIM resources............................................................................................................................................................................................ 98

∙Displaying PIM Sparse configuration information and statistics......................................................................................................... 100

∙Clearing the PIM forwarding cache...........................................................................................................................................................................111

∙Displaying PIM traffic statistics....................................................................................................................................................................................111

∙Clearing the PIM message counters...................................................................................................................................................................... 113

∙Displaying PIM RPF........................................................................................................................................................................................................ 113

∙Configuring Multicast Source Discovery Protocol (MSDP)...................................................................................................................... 113

∙Configuring MSDP mesh groups ......................................................................................................................................................................... 126

∙MSDP Anycast RP......................................................................................................................................................................................................... 128

∙PIM Anycast RP............................................................................................................................................................................................................... 132

∙Static multicast routes...................................................................................................................................................................................................134

∙IGMP Proxy.........................................................................................................................................................................................................................134

∙IGMP V3................................................................................................................................................................................................................................137

Overview of IP multicasting

Multicast protocols allow a group or channel to be accessed over different networks by multiple stations (clients) for the receipt and

transmission of multicast data.

Distribution of stock quotes, video transmissions such as news services and remote classrooms, and video conferencing are all

examples of applications that use multicast routing.

Brocade devices support the Protocol-Independent Multicast (PIM) protocol, along with the Internet Group Membership Protocol

(IGMP).

PIM is a broadcast and pruning multicast protocol that delivers IP multicast datagrams. This protocol employs reverse path lookup

check and pruning to allow source-specific multicast delivery trees to reach all group members. PIM builds a different multicast tree for

each source and destination host group.

Multicast terms

The following terms are commonly used in discussing multicast-capable devices. These terms are used throughout this chapter:

Node: A device.

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Root Node: The node that initiates the tree building process. It is also the device that sends the multicast packets down the multicast

delivery tree.

Upstream: The direction from which a device receives multicast data packets. An upstream device is a node that sends multicast

packets.

Downstream: The direction to which a device forwards multicast data packets. A downstream device is a node that receives multicast

packets from upstream transmissions.

Group Presence: A multicast group has been learned from one of the directly connected interfaces. Members of the multicast group are

present on the device.

Intermediate nodes: Devices that are in the path between source devices and leaf devices.

Leaf nodes: Devices that do not have any downstream devices.

Multicast Tree: A unique tree is built for each source group (S,G) pair. A multicast tree is comprised of a root node and one or more

nodes that are leaf or intermediate nodes.

Support for Multicast Multi-VRF

Multicast Multi-VRF support for the Brocade device includes the following:

∙PIM (PIM-SM and PIM-DM) The procedure for configuring PIM within a VRF instance is described in the “Enabling PIM on the

device and an interface” and the “Configuring global PIM Sparse parameters” sections.

system-max command changes

Several changes have been made to thesystem-max commands in support of Multicast Multi-VRF.

The system-max pim-mcache command has been deprecated and replaced by the system max pim-hw-mcache command.

The following new runtime commands have been introduced:

max-mcache This command is described in the “Defining the maximum number of PIM cache entries” section.

ip igmp max-group-address This command, which is described in the “Defining the maximum number of IGMP group ” section,

addresses replaces the system-max igmp-max-group-address command.

Show and clear command support

The following show and clear commands support Multicast Multi-VRF:

∙clear ip igmp [ vrf vrf-name ] cache

∙clear ip igmp [ vrf vrf-name ] traffic

∙show ip igmp [vrf vrf-name] group [group-address [detail] [tracking]]

∙show ip igmp [vrf vrf-name] interface [ve number | ethernet unit/slot/port | tunnel num]

∙show ip igmp [vrf vrf-name] settings

∙show ip igmp [vrf vrf-name] traffic

Changing global IP multicast parameters

The following sections apply to PIM-DM, PIM-SM, and IGMP.

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Concurrent support for multicast routing and snooping

Multicast routing and multicast snooping instances work concurrently on the same device. For example, you can configure PIM routing

on certain VEs interfaces and snooping on other VEs or VLANs. The limitation is that either multicast snooping or routing can be

enabled on a VE interface or VLAN, but not on both. This is because all of the multicast data and control packets (IGMP, PIM) received

on the snooping VLAN are handled by multicast snooping and do not reach the multicast routing component. Similarly, any multicast

data or control packets received on a VE interface enabled with PIM routing are handled by the PIM routing component and are not seen

by the IGMP or PIM snooping component.

The following considerations apply when configuring concurrent operation of Multicast Routing and Snooping.

1. Either multicast snooping or routing can be enabled on a VE or VLAN but not both.

2. Snooping can be enabled globally by configuring the ip multicast

active

passive

command.

3. The global snooping configuration is inherited by all current VLANs that are not enabled for multicast routing.

4. The global snooping configuration is also inherited by all new VLANs. Enabling multicast routing on a newly created VLAN or

VE automatically disables snooping on the VLAN or VE.

5. When a VLAN-level snooping is configured, it is displayed.

Defining the maximum number of PIM cache entries

You can use the following run-time command to define the maximum number of repeated PIM traffic being sent from the same source

address and being received by the same destination address. To define this maximum for the default VRF, enter the following

commands.

device(config)# router pim

device(config-pim-router)# max-mcache 999

Syntax: [no] max-cache

num

The

num

variable specifies the maximum number of multicast cache entries for PIM in the default VRF. If not defined by this command,

the maximum value is determined by the system-max pim-hw-mcache command or by available system resources.

To define the maximum number of PIM Cache entries for a specified VRF, use the following command.

device(config)# router pim vrf vpn1

device(config-pim-router-vrf-vpn1)# max-mcache 999

Syntax: [no] router pim [ vrf

vrf-name

]

The vrf parameter specified with the router pim command allows you to configure the max-mcache command for a virtual routing and

forwarding (VRF) instance specified by the

vrf-name

variable.

The

num

variable specifies the maximum number of multicast cache entries for PIM in the specified VRF. If not defined by this

command, the maximum value is determined by the system-max command option pim-hw-mcache or by available system resources.

Defining the maximum number of IGMP group addresses

You can use the ip igmp max-group-address run-time command to set the maximum number of IGMP addresses for the default virtual

routing and forwarding (VRF) instance or for a specified VRF. To define this maximum for the default VRF, enter the following command.

device(config)# ip igmp max-group-address 1000

Syntax: [no] ip igmp max-group-address

num

The

num

variable specifies the maximum number of IGMP group addresses for all VRFs, including the default VRF. If not defined by

this command, the maximum value is determined by available system resources.

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To define this maximum for a specified VRF, enter the following commands.

device(config)# vrf vpn1

device(config-vrf-vpn1)# address-family ipv4

device(config-vrf-vpn1-ipv4)# ip igmp max-group-address 1000

Syntax: [no] vrf

vrf-name

Syntax: [no] address-family ipv4

Syntax: [no] ip igmp max-group-address

num

The vrf parameter specifies the VRF instance specified by the

vrf-name

variable.

The

num

parameter specifies the number of IGMP group addresses that you want to make available for the specified VRF. If not defined

by this command, the maximum value is determined by available system resources.

Changing IGMP V1 and V2 parameters

IGMP allows Brocade devices to limit the multicast of IGMP packets to only those ports on the device that are identified as IP Multicast

members.

The device actively sends out host queries to identify IP Multicast groups on the network, inserts the group information in an IGMP

packet, and forwards the packet to IP Multicast neighbors.

The following IGMP V1 and V2 parameters apply to PIM:

∙IGMP query interval - Specifies how often the Brocade device queries an interface for group membership. Possible values are

2 - 3600. The default is 125.

∙IGMP group membership time - Specifies how many seconds an IP Multicast group can remain on a Brocade device interface

in the absence of a group report. Possible values are 5 - 26000. The default is 260.

∙IGMP maximum response time - Specifies how many seconds the Brocade device will wait for an IGMP response from an

interface before concluding that the group member on that interface is down and removing the interface from the group.

Possible values are 1 - 25. The default is 10.

Modifying IGMP (V1 and V2) query interval period

The IGMP query interval period defines how often a device will query an interface for group membership. Possible values are 2 to 3600

seconds and the default value is 125 seconds.

To modify the default value for the IGMP (V1 and V2) query interval, enter the following:

Device(config)# ip igmp query-interval 120

Syntax: [no] ip igmp query-interval

num

The

num

variable specifies the number of seconds and can be a value from 2 to 3600.

The default value is 125.

Modifying IGMP (V1 and V2) membership time

Group membership time defines how long a group will remain active on an interface in the absence of a group report. Possible values

are from 5 to 26000 seconds and the default value is 260 seconds.

To define an IGMP (V1 and V2) membership time of 240 seconds, enter the following.

device(config)# ip igmp group-membership-time 240

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Syntax: [no] ip igmp group-membership-time

num

The

num

variable specifies the number of seconds and can be a value from 5 to 26000.

The default value is 260.

Modifying IGMP (V1 and V2) maximum response time

Maximum response time defines how long the Brocade device will wait for an IGMP (V1 and V2) response from an interface before

concluding that the group member on that interface is down and removing the interface from the group. Possible values are 1 to 25. The

default is 10.

To change the IGMP (V1 and V2) maximum response time, enter a command such as the following at the global CONFIG level of the

CLI.

Device(config)# ip igmp max-response-time 8

Syntax:[no] ip igmp max-response-time

num

The

num

variable specifies the number of seconds and can be a value from 1 to 25. The default is 10.

Security enhancement for IGMP

A security enhancement was made to IGMPv2 to comply with the following recommendation of RFC 2236: “Ignore the Report if you

cannot identify the source address of the packet as belonging to a subnet assigned to the interface on which the packet was received.”

NOTE

When used in applications such as IP-TV (or any multicast application in general), the administrator should ensure that the set-

top box (or multicast client) is configured on the same subnet as the v.e. configured on the device. This is typically the case but

is emphasized here to ensure correct operation. Without this configuration, IGMP messages received by the device are ignored,

which causes an interruption in any multicast traffic directed towards the set-top box (multicast client).

Adding an interface to a multicast group

You can manually add an interface to a multicast group. This is useful in the following cases:

∙Hosts attached to the interface are unable to add themselves as members of the group using IGMP.

∙There are no members for the group attached to the interface.

When you manually add an interface to a multicast group, the device forwards multicast packets for the group but does not itself accept

packets for the group.

You can manually add a multicast group to individual ports only. If the port is a member of a virtual routing and forwarding (VRF)

interface, you must add the ports to the group individually.

To manually add a port to a multicast group, enter a command such as the following at the configuration level for the port.

Device(config-if-e10000-1/1/1)# ip igmp static-group 224.2.2.2

This command adds port 1/1 to multicast group 224.2.2.2.

To add a port that is a member of a VRF interface to a multicast group, enter a command such as the following at the configuration level

for the virtual routing interface.

Device(config-vif-1)# ip igmp static-group 224.2.2.2 ethernet 1/4/2

This command adds port 1/4/2 in VRF interface 1 to multicast group 224.2.2.2.

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Syntax: [no] ip igmp static-group

ip-addr

[ ethernet

unit/slot//port

]

The

ip-addr

variable specifies the group number.

The ethernet

unit/slot//port

parameter specifies the port number. Use this parameter if the port is a member of a VRF interface, and you

are entering this command at the configuration level for the VRF interface.

Manually added groups are included in the group information displayed by the following commands:

∙show ip igmp group

∙show ip pim group

To display static multicast groups in the default VRF, enter the following command.

device#show ip igmp static

Group Address Interface Port List

----------------------------------

224.2.2.2 v1 ethe 1/4/2

Syntax: show ip igmp [ vrf

vrf_name

] static

The vrf parameter allows you to display static IGMP groups for the VRF instance specified by the

vrf_name

variable.

Multicast non-stop routing

Multicast non-stop routing (NSR) provides hitless-failover support on all platforms for IPv4 multicast features (default and non-default

VRFs): PIM-DM, PIM-SM, and PIM-SSM.

If multicast NSR is enabled, the software state is kept in sync between the active and standby modules. The standby module is NSR

ready when the software state of the standby and active modules are in sync. When the standby module is NSR ready, a hitless-failover

does not result in a disruption to the multicast forwarding state or traffic

If Multicast NSR is not enabled, or if the standby module is not NSR ready, the software state of the standby and active modules are not

in sync. In this case, after a switchover or failover occurs, the new active module enters protocol learning phase for a duration of 55

seconds. During this phase, it learns the protocol state information from its PIM neighbors and local clients. During this period, new

multicast flows will not be forwarded, but the existing mutlicast flows (which existed prior to switchover or failover) are forwarded in

hardware without any disruption. At the end of the period, all the existing flows are deleted from hardware and they are reprogrammed as

per the newly learned state information. Multicast traffic will incur a slight disturbance until the new active module reprograms the

hardware with new forwarding state information.

The following message is displayed on the console of the active and standby modules to indicate that the standby module is NSR ready:

Mcastv4 is NSR ready

NOTE

During a hitless-upgrade on FSX platforms, the new active module will always perform the 55 second deferred hardware

cleanup even if the NSR is enabled.

Configuration considerations

∙Multicast NSR is not supported for IPv6 multicast.

∙When multicast NSR is turned on, unicast routing must be protected by NSR or graceful restart on all multicast VRFs.

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Configuring multicast non-stop routing

To globally enable multicast non-stop routing for all VRFs, enter the ip multicast-nonstop-routing command on the CLI as shown in this

example:

Device(config)#ip multicast-nonstop-routing

Syntax: ip multicast-nonstop-routing

During a hitless upgrade and switchover, this syslog message is generated on the CLI. The message displayed depends on which

version of PIM is configured.

PIM v4 is configured

MCASTv4 protocol receives switchover event

Mcastv4 protocol switchover done

PIM v6 is configured

MCASTv6 protocol receives switchover event

Mcastv6 protocol switchover done

The syslog message shows the state transition of multicast NSR as the standby module takes over as the active module. The multicast

data traffic will continue to flow during state transition.

Displaying the multicast NSR status

To display the multicast nonstop routing (NSR) status, enter the following command:

Device# show ip pim nsr

Global Mcast NSR Status

NSR: ON

Switchover In Progress Mode: FALSE

The following table displays the output from the show ip pim nsr command.

Field Description

NSR The NSR field indicates whether the ip multicast-nonstop-routing

command is enabled (ON) or disabled (OFF).

Switchover in Progress Mode The Switchover in Progress Mode field indicates whether the multicast

traffic is in the middle of a switchover (displaying a TRUE status), or not

(displaying a FALSE status).

Displaying counter and statistic information for multicast NSR

To display multicast NSR counter and statistic information, enter the following command.

device#show ip pim counter nsr

Mcache sync (entity id: 203)

pack: 0

unpack: 0

ack: 0

RPset sync (entity id: 201)

pack: 0

unpack: 0

ack: 0

BSR status (entity id: 202)

pack: 1

unpack: 0

ack: 1

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Syntax: show ip pim [vrf

vrf_name

] counter nsr

The vrf parameter allows you to display IP PIM counters for the VRF instance specified by the

vrf-name

variable.

The following table displays the output from the show ip pim counter nsr command.

This field... Displays...

Mcache sync The mcache NSR sync queue that carries the NSR sync message for

mcache updates.

pack The number of NSR sync messages that are packed from the active

module to the standby module.

unpack The number of NSR sync messages that are received and unpacked by

the standby module.

ack The number of NSR sync acknowledgements received by the active

module.

RPset sync The RPset sync queue that carries the NSR sync message for RPset

update.

BSR status The BSR status sync queue that carries the NSR sync message for BSR

information update.

Passive multicast route insertion

To prevent unwanted multicast traffic from being sent to the CPU, PIM routing and passive multicast route insertion (PMRI) can be used

together to ensure that multicast streams are forwarded out only ports with interested receivers and unwanted traffic is dropped in

hardware on Layer 3 switches.

PMRI enables a Layer 3 switch running PIM Sparse to create an entry for a multicast route (for example, (S,G)), with no directly attached

clients or when connected to another PIM device (transit network).

When a multicast stream has no output interfaces (OIF), the Layer 3 switch can drop packets in hardware if the multicast traffic meets

either of the following conditions:

In PIM-SM:

∙– The route has no OIF

and

– If directly connected source passed source reverse-path forwarding (RPF) check

and

completed data registration with

reverse path (RP)

– If non directly connected source passed source RPF check.

In PIM-DM:

∙– The route has no OIF

and

– passed source RPF check

and

– Device has no downstream PIM neighbor.

If the OIF is inserted after the hardware-drop entries are installed, the hardware entries will be updated to include the OIFs.

NOTE

Disabling hardware-drop does not immediately take away existing hardware-drop entries, they will go through the normal route

aging processing when the traffic stops.

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Configuring PMRI

PMRI is enabled by default. To disable PMRI, enter commands such as the following.

device(config)# router pim

device(config-pim-router)# hardware-drop-disable

Syntax: [no] hardware-drop-disable

Displaying hardware-drop

Use the show ip pim sparse command to display if the hardware-drop feature has been enabled or disabled.

device(config)#show ip pim sparse

Global PIM Sparse Mode Settings

Maximum Mcache : 12992 Current Count : 0

Hello interval : 30 Neighbor timeout : 105

Join/Prune interval : 60 Inactivity interval : 180

Hardware Drop Enabled : Yes Prune Wait Interval : 3

Bootstrap Msg interval : 60 Candidate-RP Msg interval : 60

SSM Enabled : Yes SPT Threshold : 1

SSM Group Range : 232.0.0.0/8

Route Precedence : mc-non-default mc-default uc-non-default uc-default

IP multicast boundaries

The IP multicast boundary feature is designed to selectively allow or disallow multicast flows to configured interfaces.

The ip multicast-boundary command allows you to configure a boundary on a PIM enabled interface by defining which multicast groups

may not forward packets over a specified interface. This includes incoming and outgoing packets. By default, all interfaces that are

enabled for multicast are eligible to participate in a multicast flow provided they meet the multicast routing protocol’s criteria for

participating in a flow.

Configuration considerations

∙Only one ACL can be bound to any interface.

∙Normal ACL restrictions apply as to how many software ACLs can be created, but there is no hardware restrictions on ACLs

with this feature.

∙Creation of a static IGMP client is allowed for a group on a port that may be prevented from participation in the group on

account of an ACL bound to the port’s interface. In such a situation, the ACL would prevail and the port will not be added to the

relevant entries.

∙Either standard or extended ACLs can be used with the multicast boundary feature. When a standard ACL is used, the address

specified is treated as a group address and NOT a source address.

∙When a boundary is applied to an ingress interface, all packets destined to a multicast group that is filtered out will be dropped

by software. Currently, there is no support to drop such packets in hardware.

∙The ip multicast-boundary command may not stop clients from receiving multicast traffic if the filter is applied on the egress

interface up-stream from RP.

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Configuring multicast boundaries

To define boundaries for PIM enabled interfaces, enter a commands such as the following.

device(config)# interface ve 40

device(config-vif-40)#ip multicast-boundary MyBrocadeAccessList

Syntax: [no] ip multicast-boundary

acl-spec

Use the

acl-spec

parameter to define the number or name identifying an access list that controls the range of group addresses affected

by the boundary.

Use the no ip multicast boundary command to remove the boundary on a PIM enabled interface.

The ACL, MyBrocadeAccessList can be configured using standard ACL syntax. Some examples of how ACLs can be used to filter

multicast traffic are as follows:

Standard ACL to permit multicast traffic

To permit multicast traffic for group 225.1.0.2 and deny all other traffic, enter the following command.

device(config)# access-list 10 permit host 225.1.0.2

device(config)# access-list 10 deny any

Extended ACL to deny multicast traffic

To deny multicast data traffic from group 225.1.0.1 and permit all other traffic, enter the following command.

device(config)# access-list 101 deny ip any host 225.1.0.1

device(config)# access-list 101 permit ip any any

Extended ACL to permit multicast traffic

To permit multicast data traffic from source 97.1.1.50 for group 225.1.0.1 and deny all other traffic, enter the following commands:

Device(config)# access-list 102 permit ip host 97.1.1.50 host 225.1.0.1

Device(config)# access-list 102 deny ip any any

Displaying multicast boundaries

To display multicast boundary information, enter the show ip pim interface command.

device# show ip pim interface ethernet 1/1/7

Flags : SM - Sparse Mode v2, DM - Dense Mode v2, P - Passive Mode

---------+---------------+----+---+-----------------------+---+---------+-------+------+---------+

---------+---------------+----+---+-----------------------+---+---------+-------+------+---------+

e1/1/7 30.0.0.1 SM Ena Itself 1 None default 1 3000ms

Total Number of Interfaces : 1

Syntax: show ip pim [ vrf

vrf-name

] interface [ethernet

unit/slot/port

| loopback

num

| ve

num

| tunnel

num

]

The vrf keyword allows you to display multicast boundary information for the VRF instance identified by the

vrf-name

variable.

The ethernet parameter specifies the physical port by its unit, slot, and port number.

The loopback parameter specifies the loopback port.

The veparameter specifies a virtual interface.

The tunnel parameter specifies a GRE tunnel interface that is being configured. The GRE tunnel interface is enabled under the device

PIM configuration.

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The following table describes the output from the show ip pim interface ethernet command.

Field Description

Interface Name of the interface.

Local Address IP address of the interface.

Mode PIM mode, dense or sparse..

St PIM status for this interface, enabled or disabled.

Designated Router Address, Port Address, port number of the designated router.

TTL Thr Time to live threshold. Multicast packets with TTL less than this threshold

value are not be forwarded on this interface.

Multicast Boundary Multicast boundary ACL, if one exists.

VRF Name of the VRF.

DR Prio Designated router priority assigned to this interface.

Override Interval Effective override interval in milliseconds.

PIM Dense

NOTE

This section describes the "dense" mode of PIM, described in RFC 3973. Refer to PIM Sparse on page 89 for information

about PIM Sparse.

PIM was introduced to simplify some of the complexity of the routing protocol at the cost of additional overhead tied with a greater

replication of forwarded multicast packets. PIM builds source-routed multicast delivery trees and employs reverse path check when

forwarding multicast packets.

There are two modes in which PIM operates: Dense and Sparse. The Dense Mode is suitable for densely populated multicast groups,

primarily in the LAN environment. The Sparse Mode is suitable for sparsely populated multicast groups with the focus on WAN.

PIM uses the IP routing table instead of maintaining its own, thereby being routing protocol independent.

Initiating PIM multicasts on a network

Once PIM is enabled on each device, a network user can begin a video conference multicast from the server on R1 as shown in Figure 3

on page 79. When a multicast packet is received on a PIM-capable device interface, the interface checks its IP routing table to

determine whether the interface that received the message provides the shortest path back to the source. If the interface does provide

the shortest path back to the source, the multicast packet is then forwarded to all neighboring PIM devices. Otherwise, the multicast

packet is discarded and a prune message is sent back upstream.

In Figure 3 on page 79, the root node (R1) is forwarding multicast packets for group 229.225.0.1, which it receives from the server, to

its downstream nodes, R2, R3, and R4. Device R4 is an intermediate device with R5 and R6 as its downstream devices. Because R5

and R6 have no downstream interfaces, they are leaf nodes. The receivers in this example are those workstations that are resident on

devices R2, R3, and R6.

Pruning a multicast tree

As multicast packets reach these leaf devices, the devices check their IGMP databases for the group. If the group is not in the IGMP

database of the device, the device discards the packet and sends a prune message to the upstream device. The device that discarded

the packet also maintains the prune state for the source, group (S,G) pair. The branch is then pruned (removed) from the multicast tree.

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No further multicast packets for that specific (S,G) pair will be received from that upstream device until the prune state expires. You can

configure the PIM Prune Timer (the length of time that a prune state is considered valid).

For example, in the “Transmission of multicast packets from the source to host group members” figure, the sender with address

207.95.5.1 is sending multicast packets to the group 229.225.0.1. If a PIM device receives any groups other than that group, the device

discards the group and sends a prune message to the upstream PIM device.

In the “Pruning leaf nodes from a multicast tree” figure, device R5 is a leaf node with no group members in its IGMP database.

Therefore, the device must be pruned from the multicast tree. R5 sends a prune message upstream to its neighbor device R4 to remove

itself from the multicast delivery tree and install a prune state, as seen in the “Pruning leaf nodes from a multicast tree” figure. Device 5

will not receive any further multicast traffic until the prune age interval expires.

When a node on the multicast delivery tree has all of its downstream branches (downstream interfaces) in the prune state, a prune

message is sent upstream. In the case of R4, if both R5 and R6 are in a prune state at the same time, R4 becomes a leaf node with no

downstream interfaces and sends a prune message to R1. With R4 in a prune state, the resulting multicast delivery tree would consist

only of leaf nodes R2 and R3.

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FIGURE 3 Transmission of multicast packets from the source to host group members

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FIGURE 4 Pruning leaf nodes from a multicast tree

Grafts to a multicast tree

A PIM device restores pruned branches to a multicast tree by sending graft messages towards the upstream device. Graft messages

start at the leaf node and travel up the tree, first sending the message to its neighbor upstream device.

In the preceding example, if a new 229.255.0.1 group member joins on device R6, which was previously pruned, a graft is sent upstream

to R4. Since the forwarding state for this entry is in a prune state, R4 sends a graft to R1. Once R4 has joined the tree, R4 along with R6

once again receive multicast packets.

Prune and graft messages are continuously used to maintain the multicast delivery tree. You do not need to configure anything.

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PIM DM versions

The Brocade device supports only PIM V2. PIM DM V2 sends messages to the multicast address 224.0.0.13 (ALL-PIM-ROUTERS)

with protocol number 103.

Configuring PIM DM

NOTE

This section describes how to configure the "dense" mode of PIM, described in RFC 1075. Refer to Configuring PIM Sparse on

page 91 for information about configuring PIM Sparse.

Enabling PIM on the device and on an interface

By default, PIM is disabled. To enable PIM:

∙Enable the feature globally.

∙Configure the IP interfaces that will use PIM.

∙Enable PIM locally on the ports that have the IP interfaces you configured for PIM.

Suppose you want to initiate the use of desktop video for fellow users on a sprawling campus network. All destination workstations have

the appropriate hardware and software but the devices that connect the various buildings need to be configured to support PIM

multicasts from the designated video conference server as shown in the “Pruning leaf nodes from a multicast tree” figure.

PIM is enabled on each of the devices shown in the “Pruning leaf nodes from a multicast tree” figure, on which multicasts are expected.

You can enable PIM on each device independently or remotely from one of the devices with a Telnet connection. Follow the same steps

for each device. All changes are dynamic.

Globally enabling and disabling PIM

To globally enable PIM, enter the following command.

Device(config)# router pim

Syntax:[no] router pim

The [no] router pim command behaves in the following manner:

∙Entering a router pim command to enable PIM does not require a software reload.

∙Entering a no router pim command removes all configuration for PIM multicast on a device (router pim level) only.

Enabling PIM for a specified VRF

To enable PIM for the VRF named "blue", use the following commands.

Device(config)# router pim vrf blue

Syntax: [no] router pim [ vrf

vrf-name

]

The vrf parameter allows you to configure PIM (PIM-DM and PIM-SM) on the virtual routing and forwarding instance (VRF) specified by

the

vrf-name

variable. All PIM parameters available for the default device instance are configurable for a VRF-based PIM instance.

The [no] router pim vrf command behaves in the following manner:

∙Entering the router pim vrf command to enable PIM does not require a software reload.

∙Entering a no router pim vrf command removes all configuration for PIM multicast on the specified VRF.

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Modifying PIM global parameters

PIM global parameters come with preset values. The defaults work well in most networks, but you can modify the following parameters if

necessary:

∙Neighbor timeout

∙Hello timer

∙Prune timer

∙Prune wait timer

∙Graft retransmit timer

∙Inactivity timer

Modifying neighbor timeout

Neighbor timeout is the interval after which a PIM device will consider a neighbor to be absent. Absence of PIM hello messages from a

neighboring device indicates that a neighbor is not present.

The interval can be set between 3 and 65535 seconds, and it should not be less than 3.5 times the hello timer value. The default value

is 105 seconds.

To apply a PIM neighbor timeout value of 360 seconds to all ports on the device operating with PIM, enter the following.

Device(config)# router pim

Device(config-pim-router)# nbr-timeout 360

Syntax: [no] nbr-timeout

seconds

The default is 105 seconds. The range is 35 to 65535 seconds.

Modifying hello timer

This parameter defines the interval at which periodic hellos are sent out PIM interfaces. Devices use hello messages to inform

neighboring devices of their presence. The interval can be set between 10 and 3600 seconds, and the default rate is 30 seconds.

To apply a PIM hello timer of 120 seconds to all ports on the device operating with PIM, enter the following.

Device(config)# router pim

Device(config-pim-router)# hello-timer 120

Syntax: [no] hello-timer

10-3600

The default is 30 seconds.

Modifying prune timer

This parameter defines how long a PIM device will maintain a prune state for a forwarding entry.

The first received multicast interface is forwarded to all other PIM interfaces on the device. If there is no presence of groups on that

interface, the leaf node sends a prune message upstream and stores a prune state. This prune state travels up the tree and installs a

prune state.

A prune state is maintained until the prune timer expires or a graft message is received for the forwarding entry. The default value is 180

seconds.

To set the PIM prune timer to 90, enter the following.

Device(config)# router pim

Device(config-pim-router)# prune-timer 90

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Syntax: [no] prune-timer

seconds

The default is 180 seconds. The range is 60 to 3600 seconds.

Modifying the prune wait timer

The prune-wait command allows you to configure the amount of time a PIM device will wait before stopping traffic to neighbor devices

that do not want the traffic. The value can be from zero to 30 seconds. The default is three seconds. A smaller prune wait value reduces

flooding of unwanted traffic.

A prune wait value of zero causes the PIM device to stop traffic immediately upon receiving a prune message. If there are two or more

neighbors on the physical port, then the prune-wait command should not be used because one neighbor may send a prune message

while the other sends a join message at the same time, or within less than three seconds.

To set the prune wait time to zero, enter the following commands.

Device(config)#router pim

Device(config-pim-router)#prune-wait 0

Syntax: [no] prune-wait

seconds

The

seconds

can be 0 - 30. A value of 0 causes the PIM device to stop traffic immediately upon receiving a prune message. The

default is 3 seconds.

To view the currently configured prune wait time, enter the show ip pim dense command as described in the Displaying basic PIM Dense

configuration information” section.

Modifying graft retransmit timer

The graft retransmit timer defines the interval between the transmission of graft messages.

A graft message is sent by a device to cancel a prune state. When a device receives a graft message, the device responds with a Graft

Ack (acknowledge) message. If this Graft Ack message is lost, the device that sent the graft message will resend it.

To change the graft retransmit timer from the default of 180 to 90 seconds, enter the following.

Device(config)# router pim

Device(config-pim-router)# graft-retransmit-timer 90

Syntax: [no] graft-retransmit-timer

seconds

The default is 180 seconds. The range is from 60 to 3600 seconds.

Modifying inactivity timer

The device deletes a forwarding entry if the entry is not used to send multicast packets. The PIM inactivity timer defines how long a

forwarding entry can remain unused before the device deletes it.

To apply a PIM inactivity timer of 90 seconds to all PIM interfaces, enter the following.

Device(config)# router pim

Device(config-pim-router)# inactivity-timer 90

Syntax: [no] inactivity-timer

seconds

The default is 180 seconds. The range is from 60 to 3600 seconds.

Selection of shortest path back to source

By default, when a multicast packet is received on a PIM-capable interface in a multi-path topology, the interface checks its IP routing

table to determine the shortest path back to the source. If the alternate paths have the same cost, the first alternate path in the table is

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picked as the path back to the source. For example, in the following example, the first four routes have the same cost back to the source.

However, 137.80.127.3 is chosen as the path to the source since it is the first one on the list. The device rejects traffic from any port other

than Port V11 on which 137.80.127.3 resides

Total number of IP routes: 19

Type Codes - B:BGP D:Connected I:ISIS S:Static R:RIP O:OSPF Cost - Dist/Metric

Destination Gateway Port Cost Type

172.17.41.4 137.80.127.3 v11 2 O

172.17.41.4 137.80.126.3 v10 2 O

172.17.41.4 137.80.129.1 v13 2 O

172.17.41.4 137.80.128.3 v12 2 O

172.17.41.8 0.0.0.0 1/2 1 D

Failover time in a multi-path topology

When a port in a multi-path topology fails, multicast devices, depending on the routing protocol being used, take a few seconds to

establish a new path, if the failed port is the input port of the downstream device.

Configuring a DR priority

The DR priority option lets you give preference to a particular device in the DR election process by assigning it a numerically higher DR

priority. This value can be set for IPv4 interfaces. To set a DR priority higher than the default value of 1, use the ip pim dr-priority

command as shown:

device(config-if-e10000-1/3/24)# ip pim dr-priority 50

Syntax: [no] ip pim dr-priority

priority-value

The

priority-value

variable is the value that you want to set for the DR priority. Optional values are: 0 - 65535. The default value is 1.

The no option removes the command and sets the DR priority back to the default value of 1.

The following information may be useful for troubleshooting.

1. If more than one device has the same DR priority on a subnet (as in the case of default DR priority on all), the device with the

numerically highest IP address on that subnet is elected as the DR.

2. The DR priority information is used in the DR election ONLY IF ALL the PIM devices connected to the subnet support the DR

priority option. If there is at least one PIM device on the subnet that does not support this option, then the DR election falls back

to the backwards compatibility mode in which the device with the numerically highest IP address on the subnet is declared the

DR regardless of the DR priority values.

Displaying basic PIM Dense configuration information

To display PIM Dense configuration information, enter the following command at any CLI level.

Device(config)# show ip pim dense

Global PIM Dense Mode Settings

Maximum Mcache : 12992 Current Count : 2

Hello interval : 30 Neighbor timeout : 105

Join/Prune interval : 60 Inactivity interval : 180

Hardware Drop Enabled : Yes Prune Wait Interval : 3

Graft Retransmit interval : 180 Prune Age : 180

Route Precedence : mc-non-default mc-default uc-non-default uc-default

Syntax: show ip pim [ vrf

vrf-name

] dense

The vrf keyword allows you to display PIM dense configuration information for the VRF instance identified by the

vrf-name

variable.

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This display shows the following information.

Field Description

Maximum Mcache The maximum number multicast cache entries allowed on the device.

Current Count The number of multicast cache entries currently used.

Hello interval How frequently the device sends hello messages out the PIM dense

interfaces.

Neighbor timeout The interval after which a PIM device will consider a neighbor to be

absent.

Join/Prune interval How long a PIM device will maintain a prune state for a forwarding entry.

Inactivity interval How long a forwarding entry can remain unused before the device deletes

it.

Hardware Drop Enabled Displays Yes if the Passive Multicast Route Insertion feature is enabled

and No if it is not.

Prune Wait Interval The amount of time a PIM device waits before stopping traffic to neighbor

devices that do not want the traffic. The value can be from zero to three

seconds. The default is three seconds.

Graft Retransmit interval The interval between the transmission of graft messages.

Prune Age The number of packets the device sends using the path through the RP

before switching to using the SPT path.

Route Precedence The route precedence configured to control the selection of routes based

on the four route types:

∙Non-default route from the mRTM

∙Default route from the mRTM

∙Non-default route from the uRTM

∙Default route from the uRTM

Displaying all multicast cache entries in a pruned state

Use the following command to display all multicast cache entries that are currently in a pruned state and have not yet aged out.

Device(config)# show ip pim prune

1 (104.1.1.2 231.0.1.1):

e2/2,2/2(150)

2 (108.1.1.100 231.0.1.1):

e2/2,2/2(150)

3 (104.1.1.2 231.0.1.2):

e2/2,2/2(150)

4 (108.1.1.100 231.0.1.2):

e2/2,2/2(150)

5 (108.1.1.100 231.0.1.3):

e2/2,2/2(150)

6 (104.1.1.2 231.0.1.4):

e2/2,2/2(150)

7 (108.1.1.100 231.0.1.4):

e2/2,2/2(150)

8 (104.1.1.2 231.0.1.5):

e2/2,2/2(150)

9 (108.1.1.100 231.0.1.5):

e2/2,2/2(150)

Total Prune entries: 9

Syntax: show ip pim [vrf

vrf-name

] prune

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Displaying all multicast cache entries

You can use the following command to display all multicast cache entries.

Brocade(config)# show ip pim mcache

IP Multicast Mcache Table

Entry Flags : SM - Sparse Mode, SSM - Source Specific Multicast, DM - Dense Mode

RPT - RPT Bit, SPT - SPT Bit, LSRC - Local Source, LRCV - Local Receiver

HW - HW Forwarding Enabled, FAST - Resource Allocated, TAG - Need For

Replication Entry

REGPROB - Register In Progress, REGSUPP - Register Suppression Timer

MSDPADV - Advertise MSDP, NEEDRTE - Route Required for Src/RP, PRUN - DM

Prune Upstream

Interface Flags: IM - Immediate, IH - Inherited, WA - Won Assert

MJ - Membership Join, MI - Membership Include, ME - Membership Exclude

BR - Blocked RPT, BA - Blocked Assert, BF - Blocked Filter, BI - Blocked IIF

Total entries in mcache: 20

1 (140.140.140.3, 225.0.0.1) in v340 (tag e1/1/8), Uptime 00:00:02 Rate 0 (DM)

Source is directly connected

Flags (0x200004e1) DM HW FAST TAG

fast ports: ethe 1/4/6 ethe 1/8/26

AgeSltMsk: 1, L2 FID: 8188, DIT: 3 , AvgRate: 0, profile: none

Forwarding_oif: 2

L3 (HW) 2:

TR(e1/4/6,e1/4/6)(VL330), 00:00:02/0, Flags: IM

e1/8/26(VL310), 00:00:02/0, Flags: IM

Src-Vlan: 340

Syntax: show ip pim mcache [

source-address

group-address

| counts | dense |

dit-idx

The

source-address

parameter selects the multicast cache source address.

The

group-address

parameter selects the multicast cache group address.

The counts keyword indicates the count of entries.

The dense keyword displays only the PIM Dense Mode entries.

The

dit-idx

variable allows you to display all entries that match a specified dit.

The g_entries keyword displays only the (*, G) entries.

The receiver keyword allows you to display all entries that egress a specified interface.

The sg_entries keyword displays only the (S, G) entries.

The sparse keyword displays only the PIM Sparse Mode entries.

The ssm keyword displays only the SSM entries.

TABLE 2 Output fields from the show ip pim mcache command

Field Description

Total entries in mcache Shows the total number of PIM mcache entries

MJ Membership Join

MI Membership Include

ME Membership Exclude - Legend for the mcache entry printed once per

page, it gives the explanation of each of the flags used in the entry.

BR Blocked RPT

BA Blocked Assert

BF Blocked Filter

BI Blocked IIF

Uptime Shows the software entry uptime.

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TABLE 2 Output fields from the show ip pim mcache command (continued)

Field Description

Rate Shows the total number of packets per second that have been forwarded

using the hardware programmed forwarding entry (the (S,G) entry

programmed in hardware or (*,G) entries if (*,G) based forwarding is

enabled). The rate is displayed for all entries when the fwd_fast flag is set

on the active module.

upstream neighbor Shows the upstream neighbor for the Source/RP based on the type of

entry. For (*,G) it shows the upstream neighbor towards the RP. For (S,G)

entries it shows the upstream neighbor towards the source.

Flags Flags Represent Entry flags in hex format in the braces. And indicates the

meaning of the flags set in abbreviated string whose explanations are as

follows. Only shows the flags which are set.

SM - Shows If the entry is created by PIM Sparse Mode

DM - Shows If DM mode entry is enabled

SSM - Shows If the SSM mode entry is enabled

RPT - Shows If the entry is on the Rendezvous Point (RP)

SPT - Shows If the entry is on the source tree

LSRC - Shows If the source is in a directly-connected interface

LRcv - Shows If the receiver is directly connected to the router

REG - if the data registration is in progress

L2REG - if the source is directly connected to the router

REGSUPP - if the register suppression timer is running

RegProbe

HW - Shows If the candidate for hardware forwarding is enabled

FAST - Shows If the resources are allocated for hardware forwarding

TAG - Shows If there is a need for allocating entries from the replication

table

MSDPADV - Shows If RP is responsible for the source and must be

advertised to its peers.

NEEDRTE - Shows If there is no route to the source and RP is available

PRUNE - Shows If PIM DM Prune to upstream is required

RP Show the IP address of the RP.

fast ports Shows forwarding port mask.

AgeSltMsk Shows the slot number on which active module expects ingress traffic.

This value is 1 if the entry is programmed in hardware and is 0 if the entry

is not programmed in hardware.

L2 FID Hardware Resource allocated for the traffic switched to receivers in the

ingress VLAN.

DIT Hardware Resource allocated for router receivers.

RegPkt Shows the number of packets forwarded due to the Register

decapsulation. This field is displayed only on the active module. This field

displays only those entries for which the device is the RP. However, for a

PIM DM entry the RegPkt field is not displayed for the (S,G) entries on the

active module.

AvgRate Shows the average rate of packets ingressing for this entry over a 30

second period. This field is displayed only on the active module for all

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TABLE 2 Output fields from the show ip pim mcache command (continued)

Field Description

entries that are hardware programmed (the fwd_fast flag is set on the

active module).

Profile Shows the Profile ID associated with the Stream.

Number of matching entries Shows the total number of mcache entries matching a particular multicast

filter specified.

Outgoing interfaces Section This section consists of three parts. L3 OIFs, L2OIFs and Blocked OIFs.

And each section has Format of L3/L2/Blocked followed by (HW/SW)

followed by count of the number of OIF in each section.

Additionally, each section displays the OIFs one per line. And shows the

OIF in the format eth/Tr(Vlan) followed by uptime/expiry time, followed by

the Flags associated with each OIF.

L3 Shows whether the traffic is routed out of the interface.

L2 Shows whether the traffic is switched out of the interface.

HW Shows whether the entry is hardware forwarded.

SW Shows whether the entry is software forwarded.

Eth/Tr(VL1) Shows the outgoing interface on the specified VLAN.

Flags (explanation of flags in the OIF section) Shows the flags set in each of the Outgoing interface in abbreviated string

format whose explanations are as follows. Legend of this shown at the top

of each entry

IM - Immediate

IH - Inherited

MJ - Membership Join

MI - Membership Include

ME - Membership Exclude

BR - Blocked due to SG RPT

BA - Blocked due to Assert

BF - Blocked due to Filter

BI - Blocked IIF (Incoming interface) matches OIF

Src-VLAN VLAN associated with the ingress interface.

MCTPEERF - Traffic Forw By Cluster Peer CCEP Applies only to Layer 3 multicast routing over MCT. This means multicast

traffic for this stream is forwarded by cluster peer [remote] CCEP port

because of flow load balancing

You can use the following command to filter the output to display only entries that egress ethernet port 1/1/1.

device#show ip pim mcache receiver ethernet 1/1/1

You can use the following command to filter the output to display only the Source Specific Multicast (SSM) routes in the mcache.

device#show ip pim mcache ssm

You can use the following command to filter the output to display only the Sparse Mode routes in the mcache.

device#show ip pim mcache sparse

You can use the following command to filter the output to display only the Dense Mode routes in the mcache.

device#show ip pim mcache dense

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You can use the following command to filter the output to display only the entries matching a specific source.

device#show ip pim mcache 1.1.1.1

You can use the following command to filter the output to display only the entries matching a specific group.

device#show ip pim mcache 239.1.1.1

Displaying information across VRFs

Use the following command to display information across all active VRFs.

Brocade#show ip pim all-vrf

bsr Bootstrap router

flow-count Show flowcache counters

hw-resource PIM hw resources

interface PIM interface

neighbor PIM neighbor states

resource PIM resources

rp-set List of rendezvous point (RP) candidates

traffic Active multicast traffic