IGMP and MLD Commands on Cisco IOS XR Software\n

IGMP and MLD Commands on Cisco IOS XR Software

This chapter describes the commands used to configure and monitor IPv4 and IPv6 protocol using Cisco IOS XR Software .

The commands in this chapter apply to these protocols:


  • Internet Group Management Protocol (IGMP) (Versions 1, 2, and 3)
  • Multicast Listener Discovery (MLD) Protocol (Versions 1 and 2)

Note


IGMP Versions 2 and 3 are equivalent to MLD Versions 1 and 2.

IGMP Version 1 does not have a complementary MLD version.


For detailed information about multicast routing concepts, configuration tasks, and examples, refer to the Implementing Multicast Routing on Cisco IOS XR Software configuration module in Cisco IOS XR Multicast Configuration Guide for the Cisco XR 12000 Series Router .

access-group (IGMP/MLD)

To set limits on an interface for multicast-group join requests by hosts, use the access-group command in the appropriate configuration mode. To return to the default behavior, use the no form of this command.

access-group access-list

no access-group access-list

Syntax Description

access-list

Number or name of a standard IP access list. Range is 1 to 99.

Command Default

No default behavior or values

Command Modes

IGMP interface configuration

MLD interface configuration

Command History

Release

Modification

Release 3.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

If this command is not specified in router Internet Group Management Protocol (IGMP) or Multicast Listener Discovery (MLD) configuration mode, the interface accepts all multicast join requests by hosts.

Task ID

Task ID

Operations

multicast

read, write

Examples

In the following example, hosts serviced by GigabitEthernet interface 0/1/0/1 can join only group 225.2.2.2:

RP/0/0/CPU0:router# configure
RP/0/0/CPU0:router(config)# ipv4 access-list mygroup permit 225.2.2.2 0.0.0.0
RP/0/0/CPU0:router(config)# router igmp
RP/0/0/CPU0:router(config-igmp)# interface GigE 0/1/0/1
RP/0/0/CPU0:router(config-igmp-default-if)# access-group mygroup
RP/0/0/CPU0:router# configure
RP/0/0/CPU0:router(config)# ipv4 access-list mygroup permit 225.2.2.2 0.0.0.0
RP/0/0/CPU0:router(config)# router igmp
RP/0/0/CPU0:router(config-igmp)# interface GigE 0/1/0/1
RP/0/0/CPU0:router(config-igmp-default-if)# access-group mygroup

In the following example, an access group is configured for IPv6:

RP/0/0/CPU0:router# configure
RP/0/0/CPU0:router(config)# ipv6 access-list mld-acl
RP/0/0/CPU0:router(config-ipv6-acl)# 10 permit ipv6 any host ff3e::8000:1bb8
RP/0/0/CPU0:router(config-ipv6-acl)# exit
RP/0/0/CPU0:router(config)# router mld 
RP/0/0/CPU0:router(config-mld)# access-group mld-acl

Related Commands

Command

Description

ipv4 access-list

Defines a standard IP access list. For information, see Cisco IOS XR IP Addresses and Services Command Reference for the Cisco XR 12000 Series Router

clear igmp counters

To clear IGMP traffic statistics, use the clear igmp counters command in EXEC mode.

clear igmp [ ipv4 vrf vrf-name | vrf vrf-name ] counters

Syntax Description

ipv4

(Optional) Specifies IPv4 addressing. IPv4 is the default for Internet Group Management Protocol (IGMP) groups.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

After IGMP statistics are cleared, statistics begin incrementing again.

Task ID

Task ID

Operations

multicast

execute

Examples

The following example shows sample output before and after clearing IGMP traffic statistics:

RP/0/0/CPU0:routershow igmp traffic

IGMP Traffic Counters
Elapsed time since counters cleared: 00:00:19

                                  Received        Sent
Valid IGMP Packets                       0          12
Queries                                  0           3
Reports                                  0           9
Leaves                                   0           0
Mtrace packets                           0           0
DVMRP packets                            0           0
PIM packets                              0           0

Errors:
Malformed Packets                                    0
Bad Checksums                                        0
Socket Errors                                        0
Bad Scope Errors                                     0
Auxiliary Data Len Errors 0
Subnet Errors                                        0
Packets dropped due to invalid socket                0
Packets which couldn't be accessed                   0
Other packets drops                                  0 

RP/0/0/CPU0:routerclear igmp counters 

RP/0/0/CPU0:routershow igmp traffic 

IGMP Traffic Counters
Elapsed time since counters cleared: 00:00:12

                                  Received        Sent
Valid IGMP Packets                       0           1
Queries                                  0           1
Reports                                  0           0
Leaves                                   0           0
Mtrace packets                           0           0
DVMRP packets                            0           0
PIM packets                              0           0

Errors:
Malformed Packets                                    0
Bad Checksums                                        0
Socket Errors                                        0
Bad Scope Errors                                     0
Auxiliary Data Len Errors                            0
Subnet Errors                                        0
Packets dropped due to invalid socket                0
Packets which couldn't be accessed                   0
Other packets drops                                  0

Related Commands

Command

Description

show igmp traffic

Displays all the Internet Group Management Protocol (IGMP) traffic-related counters.  

clear igmp group

To clear Internet Group Management Protocol (IGMP) groups on one or all interfaces, use the clear igmp group command in EXEC mode.

clear igmp [ ipv4 vrf vrf-name | vrf vrf-name ] group [ ip-address | type interface-path-id ]

Syntax Description

ipv4

(Optional) Specifies IPv4 addressing. IPv4 is the default for IGMP groups.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

ip-address

(Optional) IP hostname or group address.

type

(Optional) Interface type. For more information, use the question mark (?) online help function.

interface-path-id

(Optional) Physical interface or virtual interface.

Note   

Use the show interfaces command to see a list of all interfaces currently configured on the router.

For more information about the syntax for the router, use the question mark (?) online help function.

Command Default

If no group address is specified, all IGMP groups are cleared.

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

To clear all IGMP groups, use the clear igmp group command without using an argument. To clear a particular group, use the ip-address or type interface-path-id arguments.

The following groups cannot be cleared:


  • 224.0.0.2
  • 224.0.0.13
  • 224.0.0.22
  • 224.0.0.40

Task ID

Task ID

Operations

multicast

execute

Examples

The following example uses the show igmp groups command to display the IGMP Connected Group Membership, the clear igmp group command to clear address 239.1.1.1, and the show igmp groups command again to display the updated list.

RP/0/0/CPU0:routershow igmp groups tenGigE 0/4/0/0 

IGMP Connected Group Membership
Group Address   Interface                     Uptime    Expires   Last Reporter
224.0.0.2       TenGigE0/4/0/0                3w6d      never     10.114.8.44
224.0.0.5       TenGigE0/4/0/0                3w6d      never     10.114.8.44
224.0.0.6       TenGigE0/4/0/0                3w6d      never     10.114.8.44
224.0.0.13      TenGigE0/4/0/0                3w6d      never     10.114.8.44
224.0.0.22      TenGigE0/4/0/0                3w6d      never     10.114.8.44

RP/0/0/CPU0:routerclear igmp groups tenGigE 0/4/0/0

RP/0/0/CPU0:routershow igmp groups tenGigE 0/4/0/0

IGMP Connected Group Membership
Group Address   Interface                     Uptime    Expires   Last Reporter
224.0.0.2       TenGigE0/4/0/0                3w6d      never     10.114.8.44
224.0.0.5       TenGigE0/4/0/0                3w6d      never     10.114.8.44
224.0.0.6       TenGigE0/4/0/0                3w6d      never     10.114.8.44
224.0.0.13      TenGigE0/4/0/0                3w6d      never     10.114.8.44
224.0.0.22      TenGigE0/4/0/0                3w6d      never     10.114.8.44

Related Commands

Command

Description

show igmp groups

Displays the multicast groups that are directly connected to the router and that were learned through Internet Group Management Protocol (IGMP).  

clear igmp reset

To clear all Internet Group Management Protocol (IGMP) membership entries and reset connection in the Multicast Routing Information Base (MRIB), use the clear igmp reset command in EXEC mode.

clear igmp [ ipv4 vrf vrf-name | vrf vrf-name ] reset

Syntax Description

ipv4

(Optional) Specifies IPv4 addressing. IPv4 is the default for IGMP groups.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Every IGMP group membership that IGMP learns is downloaded to the MRIB database.

The clear igmp reset command is used to clear all information from the IGMP topology table and reset the MRIB connection.


Note


This command is reserved to force synchronization of IGMP and MRIB entries when communication between the two components is malfunctioning.


Task ID

Task ID

Operations

multicast

execute

Examples

The following example shows how to clear the group memberships in MRIB:

RP/0/0/CPU0:router# clear igmp reset

Related Commands

Command

Description

show igmp groups

Displays the multicast groups that are directly connected to the router and that were learned through IGMP

show mrib route

Displays all route entries in the MRIB table.

clear mld counters

To clear Multicast Listener Discovery (MLD) traffic statistics, use the clear mld counters command in EXEC mode.

clear mld [ ipv6 vrf vrf-name | vrf vrf-name ] counters

Syntax Description

ipv6

(Optional) Specifies IPv6 addressing. IPv6 is the default for MLD groups.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

After MLD statistics are cleared, statistics begin incrementing once again.

Task ID

Task ID

Operations

multicast

execute

Examples

The following example shows how to clear MLD traffic statistics:

RP/0/0/CPU0:routerclear mld counters  

Note


See the clear igmp counters command examples for complete output.


Related Commands

Command

Description

show mld traffic

Displays all the Multicast Listener Discovery (MLD) traffic-related counters.  

clear mld group

To clear Multicast Listener Discovery (MLD) groups on one or all interfaces, use the clear mld group command in EXEC mode.

clear mld [ ipv6 vrf vrf-name | vrf vrf-name ] group [ type path-id ]

Syntax Description

ipv6

(Optional) Specifies IPv6 addressing. IPv6 is the default for MLD groups.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

type

(Optional) Interface type. For more information, use the question mark (?) online help function.

path-id

(Optional) Physical interface or virtual interface.

Note   

Use the show interfaces command in EXEC mode to see a list of all interfaces currently configured on the router.

For more information about the syntax for the router, use the question mark (?) online help function.

Command Default

If no group address is specified, all MLD groups are cleared.

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The clear mld group command is used to clear user-specified MLD membership or all MLD membership learned from external hosts. Use the type and number arguments to clear specific MLD membership, or if no interface arguments are specified, clear MLD membership from all interfaces. This command does not clear local static group members.

Task ID

Task ID

Operations

multicast

execute

Examples

The following example shows how to clear MLD groups for Packet-over-SONET/SDH (POS) interface 0/4/0/0:

RP/0/0/CPU0:routerclear mld group pos 0/4/0/0

Note


See the clear igmp group command examples for complete output.


Related Commands

Command

Description

clear igmp group

Clears Internet Group Management Protocol (IGMP) groups on one or all interfaces.  

show mld groups

Displays the multicast groups that are directly connected to the router and that were learned through Multicast Listener Discovery (MLD).  

clear mld reset

To clear all Multicast Listener Discovery (MLD) membership entries and reset connection in the Multicast Routing Information Base (MRIB), use the clear mld reset command in EXEC mode.

clear mld [ ipv6 vrf vrf-name | vrf vrf-name ] reset

Syntax Description

ipv6

(Optional) Specifies IPv6 addressing. IPv6 is the default for MLD groups.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Every MLD group membership that MLD learns is downloaded to the MRIB database.

The clear mld reset command is used to clear all information from the MLD topology table and reset the MRIB connection.


Note


This command is reserved to force synchronization of MLD and MRIB entries when communication between the two components is malfunctioning.


Task ID

Task ID

Operations

multicast

execute

Examples

The following example shows how to clear the group memberships in MRIB:

RP/0/0/CPU0:router# clear igmp mld reset

Related Commands

Command

Description

show mld groups

Displays the multicast groups that are directly connected to the router and that were learned through MLD.

show mrib route

Displays all route entries in the MRIB table.

explicit-tracking

To configure explicit host tracking under Internet Group Management Protocol (IGMP) Version 3 or Multicast Listener Discovery (MLD) Version 2, use the explicit-tracking command in the appropriate configuration mode. To disable explicit host tracking, use the no form of this command.

explicit-tracking [ access-list | disable ]

no explicit-tracking

Syntax Description

access-list

(Optional) Access list that specifies the group range for host tracking.

disable

(Optional) Disables explicit host tracking on a specific interface. This option is available only in interface configuration mode.

Command Default

If this command is not specified in IGMP or MLD configuration mode, then explicit host tracking is disabled.

Command Modes

IGMP VRF configuration

IGMP interface configuration

MLD configuration

MLD interface configuration

Command History

Release

Modification

Release 3.2

This command was supported.

Release 3.3.0

The enable keyword was removed. The disable keyword was removed from IGMP and MLD configuration modes.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

By default, IGMP supports Version 3, unless a Version 2 or Version 1 IGMP host message is detected in the network. For backward compatibility, IGMP downgrades to run at the IGMP version level that is installed.

This feature allows the router to achieve minimal leave latencies when hosts leave a multicast group or channel. To monitor IGMP or MLD membership of hosts, use the show igmp groups or the show mld groups command in EXEC mode.

In router configuration mode, the explicit-tracking command enables explicit host tracking for all interfaces.To disable explicit tracking for all interfaces, use the no form of the command from IGMP configuration mode. To disable the feature on specific interfaces, use the explicit-tracking command in interface configuration mode with the disable keyword, as shown in the following example.


Note


If you configure this command in IGMP VRF or MLD configuration mode, parameters are inherited by all new and existing interfaces. However, you can override these parameters on individual interfaces from IGMP or router MLD interface configuration mode.


Task ID

Task ID

Operations

multicast

read, write

Examples

The following example shows how to enable explicit host tracking for the access list named router1 on all interfaces and how to disable explicit host tracking for a specific GigabitEthernet interface:

RP/0/0/CPU0:router(config)# router igmp
RP/0/0/CPU0:router(config-igmp)# explicit-tracking router1
RP/0/0/CPU0:router(config-igmp)# interface GigabitEthernet 0/1/0/0
RP/0/0/CPU0:router(config-igmp-default-if)# explicit-tracking disable

Related Commands

Command

Description

show igmp groups

Displays the multicast groups that are directly connected to the router and that were learned through Internet Group Management Protocol (IGMP).  

show mld groups

Displays the multicast groups that are directly connected to the router and that were learned through Multicast Listener Discovery (MLD).  

join-group

To have the router join a multicast group, use the join-group command in the appropriate configuration mode. To return to the default behavior, use the no form of this command.

join-group group-address [source-address]

no join-group group-address [source-address]

Syntax Description

group-address

Address of the multicast group. This is a multicast IP address group in either IPv4 or IPv6 prefixing format:


  • IP address as defined in the Domain Name System (DNS) hosts table or with the domain IPv4 host in the format A.B.C.D .
  • IP address as defined in the Domain Name System (DNS) hosts table or with the domain IPv6 host in the form of X:X::X .

source-address

(Optional) Source address of the multicast group to include in either IPv4 or IPv6 prefixing format:


  • IP address as defined in the Domain Name System (DNS) hosts table or with the domain IPv4 host in the format A.B.C.D .
  • IP address as defined in the Domain Name System (DNS) hosts table or with the domain IPv6 host in the form of X:X::X .

Command Default

No multicast group memberships are predefined. If not specified, include is the default.

Command Modes

IGMP interface configuration

MLD interface configuration

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The include include-address and exclude exclude-address keywords and arguments have been removed.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The join-group command permits the IP packets that are addressed to the group address to pass to the IP client process in the Cisco IOS XR software.

If all the multicast-capable routers that you administer are members of a multicast group, pinging that group causes all routers to respond. This command can be a useful administrative and debugging tool.

Another reason to have a router join a multicast group is when other hosts on the network are prevented from correctly answering IGMP or MLD queries. When the router joins the multicast group, upstream devices learn multicast routing table information for that group and keep the paths for that group active.


Caution


Joining a multicast group can result in a significant performance impact, because all subscribed multicast packets are punted to the route processor.


Task ID

Task ID

Operations

multicast

read, write

Examples

In the following example, the router joins multicast group 225.2.2.2:

		RP/0/0/CPU0:router(config)# router igmp
		RP/0/0/CPU0:router(config-igmp)# interface GigabitEthernet 0/1/0/0
		RP/0/0/CPU0:router(config-igmp-default-if)# join-group 225.2.2.2
		
		 

Related Commands

Command

Description

ping

Checks host reachability and network connectivity on IP networks. For information, see Cisco IOS XR IP Addresses and Services Command Reference for the Cisco XR 12000 Series Router.

maximum groups

To configure the maximum number of groups used by Internet Group Management Protocol (IGMP) or Multicast Listener Discovery (MLD) and accepted by a router, use the maximum groups command in the appropriate configuration mode. To return to the default behavior, use the no form of this command.

maximum groups number

no maximum groups

Syntax Description

number

Maximum number of groups accepted by a router. Range is 1 to 75000.

Command Default

number : 50000

Command Modes

IGMP configuration

IGMP VRF configuration

MLD configuration

MLD VRF configuration

Command History

Release

Modification

Release 2.0

This command was introduced.

Release 3.2

Support was added for MLD Protocol (Versions 1 and 2).

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

When configuring this command within IGMP VRF configuration mode, you may either use the default (unspecified) VRF or a specific VRF by specifying its name.

The maximum combined number of groups on all interfaces can be 75000. After the maximum groups value is met, all additional memberships learned are ignored. The maximum number includes external and local membership.

The following groups obtain local membership on each interface when multicast is enabled and are added into the group totals for each interface: 224.0.0.13 (for PIM), 224.0.0.22 and 224.0.0.2 (for IGMP).

You cannot use the maximum groups command to configure the maximum number of groups below the number of existing groups. For instance, if the number of groups is 39, and you set the maximum number of groups to 10, the configuration is rejected.

Although Cisco IOS XR Software Release 3.9.0 supports 40,000 groups per interface, the ASR9000 router supports a maximum of 16,000 multicast routes per system.

Furthermore, you can use the maximum groups per-interface command to configure the maximum number of groups for each interface accepted by a router.

Task ID

Task ID

Operations

multicast

read, write

Examples

The following example shows how to display the number of groups (39) and the maximum number of groups configured (50000). Through use of the maximum groups command, a configuration is committed to change the maximum number of groups to 40. Before and after configuration, the show igmp summary command is used to confirm the configuration change:

RP/0/0/CPU0:router# show igmp summary

IGMP summary

Robustness Value 2
No. of Group x Interfaces 61
Maximum number of Group x Interfaces 50000

Supported Interfaces   : 18
Unsupported Interfaces : 2
Enabled Interfaces     : 18
Disabled Interfaces    : 2

Interface                 Grp No    Max Grp No
MgmtEth0/RSP0/CPU0/0      0         25000
Loopback0                 4         25000 
Bundle-POS24              3         25000 
Bundle-Ether28            3         25000 
Bundle-Ether28.1          3         25000 
Bundle-Ether28.2          3         25000 
Bundle-Ether28.3          3         25000 
MgmtEth0/RP1/CPU0/0       0         25000 
GigabitEthernet0/1/5/0    3         25000 
GigabitEthernet0/1/5/1    5         25000 
GigabitEthernet0/1/5/2    5         25000 
POS0/1/0/1                5         25000 
POS0/1/4/2                3         25000 
GigabitEthernet0/6/5/1    3         25000 
GigabitEthernet0/6/5/2    3         25000 
GigabitEthernet0/6/5/7    3         25000 
POS0/6/0/1                3         25000 
POS0/6/4/4                3         25000 
POS0/6/4/5                3         25000 
POS0/6/4/6                3         25000 

RP/0/0/CPU0:router# configure
RP/0/0/CPU0:router(config)# router igmp
RP/0/0/CPU0:router(config-igmp)# maximum groups 10
RP/0/0/CPU0:router(config-igmp)# commit

% Failed to commit one or more configuration items during an atomic operation, n
o changes have been made. Please use 'show configuration failed' to view the errors

RP/0/0/CPU0:router# show configuration failed

[!! CONFIGURATION FAILED DUE TO SEMANTIC ERRORS
router igmp
maximum groups 10
!!% Invalid argument: The desired new maximum for the number of groups 10 must be equal or larger than the present number of groups, which is 61

RP/0/0/CPU0:router# configure
RP/0/0/CPU0:router(config)# router igmp
RP/0/0/CPU0:router(config-igmp)# maximum groups 65
RP/0/0/CPU0:router(config-igmp)# commit

RP/0/0/CPU0:routerMay 13 12:26:59.108 : config[65704]: %LIBTARCFG-6-COMMIT : Configuration committed 
by user 'cisco'. Use 'show commit changes 1000000025' to view the changes.

RP/0/0/CPU0:router# show igmp summary

Robustness Value 2
No. of Group x Interfaces 61
Maximum number of Group x Interfaces 65

Supported Interfaces   : 18
Unsupported Interfaces : 2
Enabled Interfaces     : 18
Disabled Interfaces    : 2

Interface                 Grp No    Max Grp No
MgmtEth0/RP0/CPU0/0       0         25000 
Loopback0                 4         25000 
Bundle-POS24              3         25000 
Bundle-Ether28            3         25000 
Bundle-Ether28.1          3         25000 
Bundle-Ether28.2          3         25000 
Bundle-Ether28.3          3         25000 
MgmtEth0/RP1/CPU0/0       0         25000 
GigabitEthernet0/1/5/0    3         25000 
GigabitEthernet0/1/5/1    5         25000 
GigabitEthernet0/1/5/2    5         25000 
POS0/1/0/1                5         25000 
POS0/1/4/2                3         25000 
GigabitEthernet0/6/5/1    3         25000 
GigabitEthernet0/6/5/2    3         25000 
GigabitEthernet0/6/5/7    3         25000 
POS0/6/0/1                3         25000 
POS0/6/4/4                3         25000 
POS0/6/4/5                3         25000 
POS0/6/4/6                3         25000 

Related Commands

Command

Description

maximum groups-per-interface

Configures the maximum number of groups for each interface accepted by a router.  

show igmp summary

Displays group membership information for Internet Group Management Protocol (IGMP).  

show mld summary

Displays group membership information for Multicast Listener Discovery (MLD).  

maximum groups-per-interface

To configure the maximum number of groups for each interface accepted by a router, use the maximum groups-per-interface command in the appropriate configuration mode. To return to the default behavior, use the no form of this command.

maximum groups-per-interface number

no maximum groups-per-interface

Syntax Description

number

Maximum number of groups accepted by a router for each interface. Range is 1 to 40000.

Command Default

number : 20000

Command Modes

IGMP configuration

IGMP VRF configuration

IGMP interface configuration

Router MLD configuration

Router MLD VRF configuration

Router MLD interface configuration

Command History

Release

Modification

Release 3.2

This command was introduced.

Support was added for Multicast Listener Discovery (MLD) Protocol (Versions 1 and 2).

Release 3.5.0

The command was changed from maximum groups per-interface to maximum groups-per-interface .

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The following groups obtain local membership on each interface when multicast is enabled and are added into the group totals for each interface: 224.0.0.13 (for Protocol Independent Multicast [PIM]), 224.0.0.22 and 224.0.0.2 (for Internet Group Management Protocol [IGMP]). The number of groups for each interface reflects both external and local group membership.


Note


You cannot use the maximum groups-per-interface command to configure the maximum number of groups for each interface below the number of existing groups on an interface. For example, if the number of groups is 39, and you set the maximum number of groups to 10, the configuration is rejected.


When you use the maximum groups-per-interface command for a specific interface, it overrides the inheritance property of this command specified under IGMP or MLD configuration mode.

Task ID

Task ID

Operations

multicast

read, write

Examples

The following example shows how to display the maximum number of groups for each interface. A configuration is committed to change the maximum number of groups for each interface to 12. Before and after configuration, use the show igmp summary command to confirm the configuration change:

RP/0/0/CPU0:router# show igmp summary 

IGMP summary

Robustness Value 2
No. of Group x Interfaces 61
Maximum number of Group x Interfaces 50000

Supported Interfaces   : 18
Unsupported Interfaces : 2
Enabled Interfaces     : 18
Disabled Interfaces    : 2

Interface                 Grp No    Max Grp No
MgmtEth0/RSP0/CPU0/0       0         25000 
Loopback0                 4         25000 
Bundle-Ether28            3         25000 
Bundle-Ether28.1          3         25000 
Bundle-Ether28.2          3         25000 
Bundle-Ether28.3          3         25000 
MgmtEth0/RP1/CPU0/0       0         25000 
GigabitEthernet0/1/5/0    3         25000 
GigabitEthernet0/1/5/1    5         25000 
GigabitEthernet0/1/5/2    5         25000 
GigabitEthernet0/6/5/1    3         25000 
GigabitEthernet0/6/5/2    3         25000 
GigabitEthernet0/6/5/7    3         25000 

RP/0/0/CPU0:router# configure
RP/0/0/CPU0:router(config)# router igmp
RP/0/0/CPU0:router(config-igmp)# maximum groups-per-interface 5
RP/0/0/CPU0:router(config-igmp)# commit


RP/0/0/CPU0:router# show igmp summary 

Robustness Value 2
No. of Group x Interfaces 61
Maximum number of Group x Interfaces 65

Supported Interfaces   : 18
Unsupported Interfaces : 2
Enabled Interfaces     : 18
Disabled Interfaces    : 2

Interface                 Grp No    Max Grp No
MgmtEth0/RSP0/CPU0/0       0         5     
Loopback0                 4         5     
Bundle-Ether28            3         5     
Bundle-Ether28.1          3         5     
Bundle-Ether28.2          3         5     
Bundle-Ether28.3          3         5     
MgmtEth0/RP1/CPU0/0       0         5     
GigabitEthernet0/1/5/0    3         5     
GigabitEthernet0/1/5/1    5         5     
GigabitEthernet0/1/5/2    5         5     
GigabitEthernet0/6/5/1    3         5     
GigabitEthernet0/6/5/2    3         5     
GigabitEthernet0/6/5/7    3         5     

The following example shows how to configure all interfaces with 3000 maximum groups per interface except Packet-over-SONET/SDH (POS) interface 0/4/0/0, which is set to 4000:

RP/0/0/CPU0:router# configure
RP/0/0/CPU0:router(config)# router igmp
RP/0/0/CPU0:router(config-igmp)# maximum groups-per-interface 3000
RP/0/0/CPU0:router(config-igmp)# interface POS 0/4/0/0
RP/0/0/CPU0:router(config-igmp-default-if)# maximum groups-per-interface 4000

Related Commands

Command

Description

maximum groups

Configures the maximum number of groups used by Internet Group Management Protocol (IGMP) or Multicast Listener Discovery (MLD) .  

show igmp summary

Displays group membership information for Internet Group Management Protocol (IGMP).  

show mld summary

Displays group membership information for Multicast Listener Discovery (MLD).  

nsf lifetime (IGMP/MLD)

To configure the maximum time for the nonstop forwarding (NSF) timeout on the Internet Group Management Protocol (IGMP) or Multicast Listener Discovery (MLD) process, use the nsf lifetime command in the appropriate configuration mode. To return to the default behavior, use the no form of this command.

nsf lifetime seconds

no nsf lifetime

Syntax Description

seconds

Maximum time for NSF mode. Range is 10 to 3600 seconds.

Command Default

seconds : 60

Command Modes

IGMP configuration

IGMP VRF configuration

MLD configuration

MLD VRF configuration

Command History

Release

Modification

Release 3.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The IGMP NSF process is triggered by the restart of the IGMP process. While in IGMP NSF mode, the Multicast Routing Information Base (MRIB) purges the routes installed by the previous IGMP process when the IGMP NSF process times out.

The IGMP NSF lifetime is the period for IGMP to relearn all the host membership of the attached network through membership queries and reports. During this NSF period, PIM continues to maintain forwarding state for the local members while IGMP recovers their membership reports.

Additionally, IGMP recovers the internal receiver state from Local Packet Transport Services (LPTS) for IP group member applications (including the Auto-RP and the Session Announcement Protocol (SAP) Listener) and updates the MRIB.


Note


The NSF process for MLD under IPv6 is as described above for IGMP under IPv4.


Task ID

Task ID

Operations

multicast

read, write

Examples

The following example shows how to set the IGMP NSF timeout value to 120 seconds:

RP/0/0/CPU0:router(config)# router igmp
RP/0/0/CPU0:router(config-igmp)# nsf lifetime 120 

Related Commands

Command

Description

nsf (multicast)

Enables NSF capability for the multicast routing system.

nsf lifetime (PIM)

Configures the NSF timeout value for the PIM process.

show igmp nsf

Displays the state of NSF operation in IGMP.

show mfib nsf

Displays the state of NSF operation for the MFIB line cards.

show mld nsf

Displays the state of NSF operation in MLD.

query-interval

To configure the frequency at which the Cisco IOS XR Software sends Internet Group Management Protocol (IGMP) or Multicast Listener Discovery (MLD) host-query messages, use the queryinterval command in the appropriate configuration mode. To return to the default frequency, use the no form of this command.

query-interval seconds

no query-interval

Syntax Description

seconds

Frequency used to send IGMP host-query messages. Range is 1 to 3600.

Command Default

If this command is not specified in interface configuration mode, the interface adopts the query interval parameter specified in IGMP or MLD configuration mode.

If this command is not specified in IGMP or MLD configuration mode, the query interval time is 60 seconds.

Command Modes

IGMP VRF configuration

IGMP interface configuration

MLD configuration

MLD interface configuration

Command History

Release

Modification

Release 3.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Multicast routers send host membership query messages (host-query messages) to discover which multicast groups have members on the attached networks of the router. Hosts respond with IGMP or MLD report messages indicating that they want to receive multicast packets for specific groups (that is, that the host wants to become a member of the group). Host-query messages are addressed to the all-hosts multicast group, which has the address 224.0.0.1, and has an IP time-to-live (TTL) value of 1.

The designated router for a LAN is the only router that sends IGMP or MLD host-query messages:


  • For IGMP Version 1 (only), the designated router is elected according to the multicast routing protocol that runs on the LAN.
  • For IGMP Versions 2 and 3, and MLD Versions 1 and 2, the designated querier is the lowest IP-addressed multicast router on the subnet.

If the router hears no queries for the timeout period (controlled by the query-timeout command), it becomes the querier.


Note


Changing the value of the seconds argument may severely impact network performance. A short query interval may increase the amount of traffic on the attached network, and a long query interval may reduce the querier convergence time.



Note


If you configure the query-interval command in IGMP or MLD configuration mode, parameters are inherited by all new and existing interfaces. You can override these parameters on individual interfaces from interface configuration mode.


Task ID

Task ID

Operations

multicast

read, write

Examples

The following example shows how to change the frequency at which the designated router sends IGMP host-query messages to 2 minutes:

RP/0/0/CPU0:router(config)# router igmp 
RP/0/0/CPU0:router(config-igmp)# interface gigabitEthernet
 
0/1/0/0 
RP/0/0/CPU0:router(config-igmp-default-if)# query-interval 120

Related Commands

Command

Description

hello-interval (PIM)

Configures the frequency of PIM hello messages.

query-timeout

Configures the timeout value before the router takes over as the querier for the interface.

show igmp groups

Displays the multicast groups that are directly connected to the router and that were learned through IGMP.

show mld groups

Displays the multicast groups that are directly connected to the router and that were learned through MLD.

query-max-response-time

To configure the maximum response time advertised in Internet Group Management Protocol (IGMP) or Multicast Listener Discovery (MLD) queries, use the querymax-response-time command in the appropriate configuration mode. To return to the default behavior, use the no form of this command.

query-max-response-time seconds

no query-max-response-time

Syntax Description

seconds

Maximum response time, in seconds, advertised in IGMP or MLD queries. Range is 1 to 12.

Command Default

If this command is not specified in interface configuration mode, the interface adopts the maximum response time parameter specified in IGMP or MLD configuration mode.

If this command is not specified in IGMP or MLD configuration mode, the maximum response time is 10 seconds.

Command Modes

IGMP VRF configuration

IGMP interface configuration

MLD configuration

MLD interface configuration

Command History

Release

Modification

Release 3.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The query-max-response-time command is not supported on IGMP Version 1.

This command is used to control the maximum response time for hosts to answer an IGMP or MLD query message. Configuring a value less than 10 seconds enables the router to prune groups much faster, but this action results in network burstiness because hosts are restricted to a shorter response time period.

If you configure this command in IGMP or MLD configuration mode, parameters are inherited by all new and existing interfaces. You can override these parameters on individual interfaces in interface configuration mode.


Note


If the hosts do not read the maximum response time in the query message correctly, group membership might be pruned inadvertently. Therefore, the hosts must know to respond faster than 10 seconds (or the value you configure).


Task ID

Task ID

Operations

multicast

read, write

Examples

The following example shows how to configure a maximum response time of 8 seconds:

RP/0/0/CPU0:router(config)# router igmp 
RP/0/0/CPU0:router(config-igmp)# interface gigabitEthernet 0/1/0/0 
RP/0/0/CPU0:router(config-igmp-default-if)# query-max-response-time 8

Related Commands

Command

Description

hello-interval (PIM)

Configures the frequency of PIM hello messages.

show igmp groups

Displays the multicast groups that are directly connected to the router and that were learned through IGMP.

show mld groups

Displays the multicast groups that are directly connected to the router and that were learned through MLD.

query-timeout

To configure the timeout value before the router takes over as the querier for the interface, use the query-timeout command in the appropriate configuration mode. To return to the default behavior, use the no form of this command.

query-timeout seconds

no query-timeout

Syntax Description

seconds

Number of seconds that the router waits after the previous querier has stopped querying before it takes over as the querier. Range is 60 to 300.

Command Default

If this command is not specified in interface configuration mode, the interface adopts the timeout value parameter specified in IGMP VRF configuration mode. If this command is not specified in IGMP VRF configuration mode, the maximum response time is equal to twice the query interval set by the query-interval command.

Command Modes

IGMP VRF configuration

IGMP interface configuration

MLD configuration

MLD interface configuration

Command History

Release

Modification

Release 3.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The query timeout command is not supported on Internet Group Management Protocol (IGMP) Version 1.

By default, the router waits twice the query interval specified by the query-interval command, after which, if the router has heard no queries, it becomes the querier. By default, the query interval is 60 seconds, which means that the query timeout value defaults to 120 seconds.

If you configure a query timeout value less than twice the query interval, routers in the network may determine a query timeout and take over the querier without good reason.


Note


If you configure this command in IGMP or MLD configuration mode, parameters are inherited by all new and existing interfaces. You can override these parameters on individual interfaces in interface configuration mode.


Task ID

Task ID

Operations

multicast

read, write

Examples

The following example shows how to configure the router to wait 30 seconds from the time it received the last query before it takes over as the querier for the interface:

RP/0/0/CPU0:router(config)# router igmp 
RP/0/0/CPU0:router(config-igmp)# interface gigabitEthernet 0/1/0/0 
RP/0/0/CPU0:router(config-igmp-default-if)# query-timeout 30

Related Commands

Command

Description

query-interval

Configures the frequency at which the Cisco IOS XR Software sends Internet Group Management Protocol (IGMP) or Multicast Listener Discovery (MLD) host-query messages.  

robustness-count

To set the robustness variable to tune for expected packet loss on a network, use the robustness-count command in the appropriate configuration mode. To return to the default setting, use the no form of this command.

robustness-count count

no robustness-count

Syntax Description

count

Value of the robustness count variable. Range is 2 to 10 packets.

Command Default

Default is 2 packets.

Command Modes

IGMP VRF configuration

IGMP interface configuration

MLD configuration

MLD interface configuration

Command History

Release

Modification

Release 3.6.0

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

IGMP is a soft-state protocol. State must be periodically refreshed or it times out. At a robustness-count command setting, for example, of 4, a network might lose three IGMP packets related to some specific state yet still maintain the state. If, however, a network lost more than three IGMP packets in the sequence, the state would time out. You might then consider changing the robustness-count setting to maintain state.

Task ID

Task ID

Operations

multicast

read, write

Examples

The following example illustrates the use of the robustness-count command:

RP/0/0/CPU0:router(config)# configure
RP/0/0/CPU0:router(config)# router igmp
RP/0/0/CPU0:router(config-igmp)# robustness-count 2

router

To disable or enable Internet Group Management Protocol (IGMP) or Multicast Listener Discovery (MLD) membership tracking, use the router command in the appropriate configuration mode. To return to the default behavior, use the no form of this command.

router { disable | enable }

no router { disable | enable }

Syntax Description

disable

Turns off IGMP or MLD membership tracking.

enable

Turns on IGMP or MLD membership tracking.

Command Default

If this command is not specified in IGMP VRF configuration mode, router functionality is enabled on all interfaces.

Command Modes

IGMP interface configuration

MLD interface configuration

Command History

Release

Modification

Release 3.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The router command is used to enable and disable the IGMP or MLD router functionality on a specific interface. For instance, IGMP or MLD stops queries from an interface when the router functionality is disabled on that interface. Disabling IGMP or MLD router functionality does not prevent local group membership from being announced through the group membership report.


Note


This command is useful if you want to disable or enable IGMP or MLD interfaces that have been previously enabled through the multicast-routing command.


Task ID

Task ID

Operations

multicast

read, write

Examples

The following example shows how to enable IGMP membership tracking functionality on all multicast enabled interfaces, except Packet-over-SONET/SDH (POS) interface 0/1/0/0:

RP/0/0/CPU0:router(config)# router igmp 
RP/0/0/CPU0:router(config-igmp)# interface gigabitEthernet 0/1/0/0 
RP/0/0/CPU0:router(config-igmp-default-if)# router enable

Related Commands

Command

Description

multicast routing

Enables multicast routing and forwarding on all enabled interfaces of the router and enters multicast routing configuration mode.

router igmp

To enter Internet Group Management Protocol (IGMP) configuration mode, use the router igmp command in global configuration mode. To return to the default behavior, use the no form of this command.

router igmp

no router igmp

Syntax Description

This command has no arguments or keywords.

Command Default

No default behavior or values

Command Default

Global configuration

Command History

Release

Modification

Release 3.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

From IGMP VRF configuration mode, you can configure the maximum response time advertised in IGMP queries and modify the host query interval.


Note


The IGMP process is turned on when the router igmp command or the multicast-routing command is initiated.


Task ID

Task ID

Operations

multicast

read, write

Examples

The following example shows how to enter IGMP configuration mode:

RP/0/0/CPU0:router(config)# router igmp
RP/0/0/CPU0:router(config-igmp)# 

Related Commands

Command

Description

interface all disable

Disables IGMP or MLD membership tracking on all interfaces.

multicast routing

Enables multicast routing and forwarding on all enabled interfaces of the router and enters multicast routing configuration mode.

router mld

To enter router Multicast Listener Discovery (MLD) Protocol configuration mode, use the router mld command in global configuration mode. To return to the default behavior, use the no form of this command.

router mld

no router mld

Syntax Description

This command has no arguments or keywords.

Command Default

No default behavior or values

Command Modes

Global configuration

Command History

Release

Modification

Release 3.2

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

From MLD configuration mode, you can configure the maximum response time advertised in MLD queries and modify the host query interval.


Note


The MLD process is turned on when the router mld command or the multicast-routing command is initiated.


Task ID

Task ID

Operations

multicast

read, write

Examples

The following example shows how to enter MLD configuration mode:

RP/0/0/CPU0:router(config)# router mld
RP/0/0/CPU0:router(config-mld)# 

Related Commands

Command

Description

multicast-routing

Enables multicast routing and forwarding on all enabled interfaces of the router and enters multicast routing configuration mode.

show igmp groups

To display the multicast groups that are directly connected to the router and that were learned through Internet Group Management Protocol (IGMP), use the show igmp groups command in EXEC mode.

show igmp [old-output] [ vrf vrf-name ] groups [ group-address | type interface-path-id | not-active | summary ] [detail] [explicit]

Syntax Description

old-output

(Optional) Displays the previous show output—available for backward compatibility.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

group-address

(Optional) Address or name of the multicast group. An address is a multicast IP address in four-part dotted-decimal notation. A name is as defined in the Domain Name System (DNS) hosts table.

type

(Optional) Interface type. For more information, use the question mark (?) online help function.

interface-path-id

(Optional) Either a physical interface or a virtual interface.

Note   

Use the show interfaces command in EXEC mode to see a list of all interfaces currently configured on the router.

For more information about the syntax for the router, use the question mark (?) online help function.

not-active

(Optional) Displays group joins that are not processed.

summary

(Optional) Displays the total number of (* , G) and (S, G) states in IGMP.

detail

(Optional) Displays detail information such as IGMP Version 3 source list, host, and router mode.

explicit

(Optional) Displays explicit tracking information.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

If you omit all optional arguments, the show igmp groups command displays (by group address and interface name) all the multicast memberships that the directly connected networks have subscribed.

Task ID

Task ID

Operations

multicast

read

Examples

The following is sample output from the show igmp groups command on a specific (tenGigE) interface:

RP/0/0/CPU0:router# show igmp groups tenGigE 0/4/0/0

IGMP Connected Group Membership
Group Address   Interface                     Uptime    Expires   Last Reporter
224.0.0.2       TenGigE0/4/0/0                3w6d      never     10.114.8.44
224.0.0.5       TenGigE0/4/0/0                3w6d      never     10.114.8.44
224.0.0.6       TenGigE0/4/0/0                3w6d      never     10.114.8.44
224.0.0.13      TenGigE0/4/0/0                3w6d      never     10.114.8.44
224.0.0.22      TenGigE0/4/0/0                3w6d      never     10.114.8.44

Table 1 describes the significant fields shown in the display.

Table 1 show igmp groups Field Descriptions

Field

Description

Group Address

Address of the multicast group.

Interface

Interface through which the group is reachable.

Uptime

How long (in hours, minutes, and seconds) this multicast group has been known.

Expires

How long (in hours, minutes, and seconds) until the entry is removed from the IGMP groups table.

Last Reporter

Last host to report being a member of the multicast group.

Related Commands

Command

Description

show igmp interface

Displays Internet Group Management Protocol (IGMP) multicast-related information about an interface.  

show igmp interface

To display Internet Group Management Protocol (IGMP) multicast-related information about an interface, use the show igmp interface command in EXEC mode.

show igmp [old-output] [ vrf vrf-name ] interface [ type inteface-path-id | state-on | state-off ]

Syntax Description

old-output

(Optional) Displays the old show output—available for backward compatibility.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

type

(Optional) Interface type. For more information, use the question mark (?) online help function.

interface-path-id

(Optional) Either a physical interface or a virtual interface.

Note   

Use the show interfaces command in EXEC mode to see a list of all interfaces currently configured on the router.

For more information about the syntax for the router, use the question mark (?) online help function.

state-on

(Optional) Displays all interfaces with IGMP enabled.

state-off

(Optional) Displays all interfaces with IGMP disabled.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

If you omit the optional arguments, the show igmp interface command displays information about all interfaces.

Task ID

Task ID

Operations

multicast

read

Examples

The following is sample output from the show igmp interface command:

RP/0/0/CPU0:router# show igmp interface

Loopback0 is up, line protocol is up
  Internet address is 10.144.144.144/32
  IGMP is enabled on interface
  Current IGMP version is 3
  IGMP query interval is 60 seconds
  IGMP querier timeout is 125 seconds
  IGMP max query response time is 10 seconds
  Last member query response interval is 1 seconds
  IGMP activity: 3 joins, 0 leaves
  IGMP querying router is 10.144.144.144 (this system)
TenGigE0/4/0/0 is up, line protocol is up
  Internet address is 10.114.8.44/24
  IGMP is enabled on interface
  Current IGMP version is 3
  IGMP query interval is 60 seconds
  IGMP querier timeout is 125 seconds
  IGMP max query response time is 10 seconds
  Last member query response interval is 1 seconds
  IGMP activity: 9 joins, 4 leaves
  IGMP querying router is 10.114.8.11 
Bundle-Ether16.162 is up, line protocol is up
  Internet address is 10.194.8.44/24
  IGMP is disabled on interface
Bundle-Ether16.163 is up, line protocol is up
  Internet address is 10.194.12.44/24
  IGMP is disabled on interface
GigabitEthernet0/1/0/2 is up, line protocol is up
  Internet address is 10.147.4.44/24
  IGMP is enabled on interface
  Current IGMP version is 3
  IGMP query interval is 60 seconds
  IGMP querier timeout is 125 seconds
  IGMP max query response time is 10 seconds
  Last member query response interval is 1 seconds
  IGMP activity: 6 joins, 0 leaves
  IGMP querying router is 10.147.4.44 (this system)
GigabitEthernet0/1/0/8 is up, line protocol is up
  Internet address is 10.146.4.44/24
  IGMP is enabled on interface
  Current IGMP version is 3
  IGMP query interval is 60 seconds
  IGMP querier timeout is 125 seconds
  IGMP max query response time is 10 seconds
  Last member query response interval is 1 seconds
  IGMP activity: 5 joins, 0 leaves
  IGMP querying router is 10.146.4.44 (this system)
GigabitEthernet0/1/0/18 is up, line protocol is up
  Internet address is 10.194.4.44/24
  IGMP is enabled on interface
  Current IGMP version is 3
  IGMP query interval is 60 seconds
  IGMP querier timeout is 125 seconds
  IGMP max query response time is 10 seconds
  Last member query response interval is 1 seconds
  IGMP activity: 7 joins, 2 leaves
  IGMP querying router is 10.194.4.19 
GigabitEthernet0/1/0/23 is up, line protocol is up
  Internet address is 10.114.4.44/24
  IGMP is enabled on interface
  Current IGMP version is 3
  IGMP query interval is 60 seconds
  IGMP querier timeout is 125 seconds
  IGMP max query response time is 10 seconds
  Last member query response interval is 1 seconds
  IGMP activity: 9 joins, 4 leaves
  IGMP querying router is 10.114.4.11 
GigabitEthernet0/1/0/27 is up, line protocol is up
  Internet address is 10.145.4.44/24
  IGMP is enabled on interface
  Current IGMP version is 3
  IGMP query interval is 60 seconds
  IGMP querier timeout is 125 seconds
  IGMP max query response time is 10 seconds
  Last member query response interval is 1 seconds
  IGMP activity: 7 joins, 2 leaves
  IGMP querying router is 10.145.4.44 (this system)

Table 1 describes the significant fields shown in the display.

Table 2 show igmp interface Field Descriptions

Field

Description

Loopback0 is up, line protocol is up

Interface type, number, and status.

Internet address is

Internet address of the interface and subnet mask being applied to the interface, as specified with the address command.

IGMP is enabled on interface

Indicates whether IGMP router functionality has been enabled on the interface.

Note   

Multicast protocols do not run on Management Ethernet interfaces even if they are enabled with the CLI.

IGMP query interval is 60 seconds

Interval at which the Cisco IOS XR software software sends Protocol Independent Multicast (PIM) query messages, as specified with the query-interval command.

IGMP querier timeout is...

Timeout that is set by nonquerier routers. When this timeout expires, the nonquerier routers begin to send queries.

IGMP max query response time is...

Query response time, in seconds, that is used by administrators to tune the burstiness of IGMP messages on the network. This is the maximum time within which a response to the query is received.

Last member query response is...

Query response time in seconds since a host replied to a query that was sent by the querier.

IGMP activity:

Total number of joins and total number of leaves received.

IGMP querying router is 239.122.41.51 (this system)

Indicates the elected querier on the link.

Related Commands

Command

Description

address

Sets a primary or secondary IP address for an interface.

query-interval

Configures the frequency at which Cisco IOS XR software sends IGMP host-query messages.

router

Disables or enables MLD or IGMP membership tracking.

show igmp nsf

To display the state of the nonstop forwarding (NSF) operation in Internet Group Management Protocol (IGMP), use the show igmp nsf command in EXEC mode.

show igmp [old-output] [ vrf vrf-name ] nsf

Syntax Description

old-output

(Optional) Displays the old show output—available for backward compatibility.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The show igmp nsf command displays the current multicast NSF state for IGMP. The NSF state that is displayed may be either normal or activated for NSF. The activated state indicates that recovery is in progress due to an IGMP failure. The total NSF timeout and time remaining are displayed until NSF expiration.

Task ID

Task ID

Operations

multicast

read

Examples

The following is sample output from the show igmp nsf command:

RP/0/0/CPU0:router# show igmp nsf 


IP IGMP Non-Stop Forwarding Status
:
	Multicast routing state: Non-Stop Forwarding Activated

NSF Lifetime: 00:01:00
NSF 
Time Remaining:       00:
00:
06

Table 1 describes the significant fields shown in the display.

Table 3 show igmp nsf Field Descriptions

Field

Description

Multicast routing state

Multicast NSF status of IGMP (Normal or Non-Stop Forwarding Activated).

NSF Lifetime

Timeout for IGMP NSF. IGMP remains in the NSF state, recovering the IGMP route state through IGMP reports for this period of time, before making the transition back to the normal state and signaling the Multicast Routing Information Base (MRIB).

NSF Time Remaining

If IGMP NSF state is activated, the time remaining until IGMP reverts to Normal mode displays.

Related Commands

Command

Description

nsf (multicast)

Enables NSF capability for the multicast routing system.

nsf lifetime (IGMP/MLD)

Configures the NSF timeout value for the IGMP or MLD process.

nsf lifetime (PIM)

Configures the NSF timeout value for the PIM process.

show mfib nsf

Displays the state of NSF operation for the MFIB line cards.

show mrib nsf

Displays the state of NSF operation in the MRIB.

show pim nsf

Displays the state of NSF operation for PIM.

show igmp summary

To display group membership information for Internet Group Management Protocol (IGMP), use the show igmp summary command in EXEC mode.

show igmp [old-output] [ vrf vrf-name ] summary

Syntax Description

old-output

(Optional) Displays the old show output—available for backward compatibility.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The show igmp summary command is used to display the total group membership. The value for number of groups is the total number of group members on all interfaces. The value for maximum number of groups is the total number of external and local members possible for all interfaces. The maximum number of groups and the default value for the maximum number of groups is 50000 members. The maximum number of groups for each interface, and the default value for the maximum number of groups for each interface, is 25000 members.

Task ID

Task ID

Operations

multicast

read

Examples

The following example shows the number of groups for each interface that are IGMP members and the maximum number of groups that can become members on each interface:

RP/0/0/CPU0:router# show igmp summary

IGMP summary

Robustness Value 2
No. of Group x Interfaces 61
Maximum number of Group x Interfaces 65

Supported Interfaces   : 18
Unsupported Interfaces : 2
Enabled Interfaces     : 18
Disabled Interfaces    : 2

Interface                 Grp No    Max Grp No
MgmtEth0/RP0/CPU0/0       0         5     
Loopback0                 4         5     
Bundle-POS24              3         5     

Bundle-Ether28            3 

5   

Bundle-Ether28.1          3         5     

Bundle-Ether28.2   

 3         5     

Bundle-Ether28.3 

 3         5     
MgmtEth0/RP1/CPU0/0       0         5     

GigabitEthernet0/1/5/0    3         5     

GigabitEthernet0/1/5/1 

5         5     

GigabitEthernet0/1/5/2 

5         5     

POS0/1/0/1       

5         5     

POS0/1/4/2                3         5     

GigabitEthernet0/
6/
5/
1 

 3         5     
GigabitEthernet0/
6/5/
2    3         5     
GigabitEthernet0/
6/5/
7 

3         5     

POS0/
6/
0/
1             

3         5     

POS0/6/
4/
4                3         5     

POS0/6/
4/
5                3         5     

POS0/6/
4/
6                3         5     

Table 1 describes the significant fields shown in the display.

Table 4 show igmp summary Field Descriptions

Field

Description

No. of Group x Interfaces

Number of multicast groups that are joined through the interface.

Maximum number of Group x Interfaces

Maximum number of multicast groups that can be joined through the interface.

Supported Interfaces

Interfaces through which the multicast groups are reachable.

Unsupported Interfaces

Number of unsupported interfaces.

Enabled Interfaces

Number of enabled interfaces.

Disabled Interfaces

Number of disabled interfaces.

Related Commands

Command

Description

show igmp groups

Displays the multicast groups that are directly connected to the router and that were learned through Internet Group Management Protocol (IGMP).  

show igmp ssm map

To query the source-specific mapping (SSM) state, use the show igmp ssm map command in EXEC mode.

show igmp [ vrf vrf-name ] ssm map [group-address] [detail]

Syntax Description

vrf

(Optional) Specifies a VPN routing and forwarding (VRF) instance to be queried.

vrf-name

(Optional) Specifies the name of the specific VRF instance.

group-address

(Optional) Specifies the address of the SSM group for which to obtain the mapping state.

detail

(Optional) Displays detailed source information.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.7.0

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Task ID

Task ID

Operations

multicast

read

Examples

The following example illustrates the use of the show igmp ssm map command:

RP/0/0/CPU0:router# show igmp ssm map 232.1.1.1 


232.1.1.1 is static with 1 source

show igmp traffic

To display all the Internet Group Management Protocol (IGMP) traffic-related counters, use the show igmp traffic command in EXEC mode.

show igmp [old-output] [ vrf vrf-name ] traffic

Syntax Description

old-output

(Optional) Displays the old show output—available for backward compatibility.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The show igmp traffic command is used to display the state of all counters for IGMP traffic. It gives information about the length of time the counters have been active and the count of different types of IGMP packets received, such as queries, leaves, and reports. Also, this command keeps a count of all the erroneous IGMP packets received.

Task ID

Task ID

Operations

multicast

read

Examples

The following is sample output from the show igmp traffic command:

RP/0/0/CPU0:router# show igmp traffic 

IGMP Traffic Counters
Elapsed time since counters cleared: 15:27:38

                                  Received        Sent
Valid IGMP Packet                     2784        5576
Queries                               0           2784
Reports                               2784        2792
Leaves                                0           0
Mtrace packets                        0           0
DVMRP packets                         0           0
PIM packets                           0           0

Errors:
Malformed Packets                                 0
Bad Checksums                                     0
Socket Errors                                     0
Bad Scope Errors                                  0
Auxiliary Data Len Error                          0
Subnet Errors                                     0
Packets dropped due to invalid socket             0
Packets which couldn’t be accessed                0

Table 1 describes the significant fields shown in the display for both the show igmp traffic and show mld traffic command, since they are identical. For information about the show mld traffic command, see show mld traffic

Table 5 show igmp traffic and show mld traffic Field Descriptions

Field

Description

Valid IGMP/MLD Packet

Total number of valid protocol packets sent and received. Valid packet types include:


  • Queries
  • Membership reports
  • Leaves

Queries

Total number of query packets sent and received. IP Multicast routers send queries to determine the multicast reception state of neighboring interfaces.

Reports

Total number of membership report packets received. Membership reports indicate either the current multicast reception state of a neighboring interface or a change to that state.

Leaves

Total number of leaves received. A leave group packet indicates that a neighboring interface no longer has multicast reception state for a particular group.

Mtrace packets

(IGMP only) Total number of Mtrace packets sent and received. Mtrace traces the route from a receiver to a source using a particular multicast address.

DVMRP packets

(IGMP only) Total number of Distance Vector Multicast Routing Protocol (DVMRP) packets sent and received. DVMRP is an Internet routing protocol that provides a mechanism for connectionless datagram delivery to a group of hosts across an internetwork. This protocol dynamically generates IP multicast delivery trees using Reverse Path Multicasting. Packet type 0x13 indicates a DVMRP packet.

PIM packets

(IGMP only) Total number of sent and received Protocol Independent Multicast (PIM) packets.

Malformed Packets

Total number of malformed packets received. A malformed packet is a packet smaller than the smallest valid protocol packet.

Bad Checksums

Total number of packets received with a bad protocol header checksum.

Note   

MLD checksum verification is performed by the ICMPv6 protocol; this counter, therefore, never increments in MLD.

Socket Errors

Total number of read and write failures on the protocol socket.

Bad Scope Errors

Total number of packets received with an invalid multicast scope.

Note   

IGMP has no invalid scopes; this counter, therefore, never increments in IGMP .

Auxiliary Data Len Errors

Total number of packets received with a non-zero auxilary data length.

Subnet Errors

Total number of packets received that were not sourced on the same subnet as the router. DVMRP and MTRACE packets received are not checked for this error as they may be validly sourced from a different subnet.

Packets dropped due to invalid socket

Total number of packets dropped due to an invalid socket.

Packets which couldn’t be accessed

Total number of packets that could not be sent or received.

This might occur if:


  • Packet buffer does not form a valid protocol packet.
  • IP header is not written to the packet.
  • Outgoing packet interface handle was not set.
  • Errors occurred calculating the protocol checksum.

Other Packet Drops

Packets dropped for any other reason.

Related Commands

Command

Description

show pim traffic

Displays PIM traffic counter information.

show mld traffic

Displays all the Multicast Listener Discovery (MLD) traffic-related counters.

show mld groups

To display the multicast groups that are directly connected to the router and that were learned through Multicast Listener Discovery (MLD), use the show mld groups command in EXEC mode.

show mld [old-output] [ vrf vrf-name ] groups [ group-address | type path-id | not-active | summary ] [detail] [explicit]

Syntax Description

old-output

(Optional) Displays the old show output—available for backward compatibility.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

group-address

(Optional) Name or address of the multicast group. Name is as defined in the Domain Name System (DNS) hosts table. Address is a multicast IP address in IPv6 format.

type

(Optional) Interface type. For more information, use the question mark (?) online help function.

path-id

Physical interface or virtual interface.

Note   

Use the show interfaces command in EXEC mode to see a list of all interfaces currently configured on the router.

For more information about the syntax for the router, use the question mark (?) online help function.

not-active

(Optional) Displays group joins that are not processed.

summary

(Optional) Displays the total number of (* , G) and (S, G) states in MLD.

detail

(Optional) Displays detail information such as MLD Version 3 source list, host, and router mode.

explicit

(Optional) Displays explicit tracking information.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

If you omit all optional arguments, the show mld groups command displays (by group address and interface name) all the multicast memberships that the directly connected networks have subscribed.

Task ID

Task ID

Operations

multicast

read

Examples

The following is sample output from the show mld groups command:

RP/0/0/CPU0:router# show mld groups

MLD Connected Group Membership

POS0/2/0/0

Group Address : ff02::2
Last Reporter : fe80::b000:ff:fe00:fb00
       Uptime : 01:56:39
      Expires : never
Group Address : ff02::d
Last Reporter : fe80::b000:ff:fe00:fb00
       Uptime : 01:56:39
      Expires : never
Group Address : ff02::16
Last Reporter : fe80::b000:ff:fe00:fb00
       Uptime : 01:56:39
      Expires : never

Table 1 describes the significant fields shown in the display.

Related Commands

Command

Description

show mld interface

Displays Multicast Listener Discovery (MLD) multicast-related information about an interface.  

show mld interface

To display Multicast Listener Discovery (MLD) multicast-related information about an interface, use the show mld interface command in EXEC mode.

show mld [old-output] [ vrf vrf-name ] interface [ type path-id | state-on | state-off ]

Syntax Description

old-output

(Optional) Displays the old show output—available for backward compatibility.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

type

(Optional) Interface type. For more information, use the question mark (?) online help function.

instance

(Optional) Physical interface or virtual interface.

Note   

Use the show interfaces command in EXEC mode to see a list of all interfaces currently configured on the router.

For more information about the syntax for the router, use the question mark (?) online help function.

state-on

(Optional) Displays all interfaces with IGMP enabled.

state-off

(Optional) Displays all interfaces with IGMP disabled.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

If you omit the optional arguments, the show mld interface command displays information about all interfaces.

Task ID

Task ID

Operations

multicast

read

Examples

The following is sample output from the show mld interface command:

RP/0/0/CPU0:router# show mld interface

Loopback0 is up, line protocol is up
  Internet address is fe80::5000:ff:fe00:5c00
  MLD is enabled on interface
  Current MLD version is 2
  MLD query interval is 125 seconds
  MLD querier timeout is 255 seconds
  MLD max query response time is 10 seconds
  Last member query response interval is 1 seconds
  MLD activity: 3 joins, 0 leaves
  MLD querying router is fe80::5000:ff:fe00:5c00 (this system)
TenGigE0/5/0/2 is up, line protocol is up
  Internet address is fe80::215:c6ff:fe3e:8c85
  MLD is enabled on interface
  Current MLD version is 2
  MLD query interval is 125 seconds
  MLD querier timeout is 255 seconds
  MLD max query response time is 10 seconds
  Last member query response interval is 1 seconds
  MLD activity: 5 joins, 0 leaves
  MLD querying router is fe80::215:c6ff:fe3e:8c85 (this system)
TenGigE0/5/0/3 is up, line protocol is up
  Internet address is fe80::215:c6ff:fe3e:8c86
  MLD is enabled on interface
  Current MLD version is 2
  MLD query interval is 125 seconds
  MLD querier timeout is 255 seconds
  MLD max query response time is 10 seconds
  Last member query response interval is 1 seconds
  MLD activity: 5 joins, 0 leaves
  MLD querying router is fe80::215:c6ff:fe3e:8c86 (this system)
TenGigE0/5/0/3.4 is up, line protocol is up
  Internet address is fe80::215:c6ff:fe3e:8c86
  MLD is enabled on interface
  Current MLD version is 2
  MLD query interval is 125 seconds
  MLD querier timeout is 255 seconds
  MLD max query response time is 10 seconds
  Last member query response interval is 1 seconds
  MLD activity: 3 joins, 0 leaves
  MLD querying router is fe80::215:c6ff:fe3e:8c86 (this system)
TenGigE0/5/0/3.5 is up, line protocol is up
  Internet address is fe80::215:c6ff:fe3e:8c86
  MLD is enabled on interface
  Current MLD version is 2
  MLD query interval is 125 seconds
  MLD querier timeout is 255 seconds
  MLD max query response time is 10 seconds
  Last member query response interval is 1 seconds
  MLD activity: 3 joins, 0 leaves
  MLD querying router is fe80::215:c6ff:fe3e:8c86 (this system)

Table 1 describes the significant fields shown in the display.

Related Commands

Command

Description

address

Sets a primary or secondary IP address for an interface.

query-interval

Configures the frequency at which Cisco IOS XR Software sends MLD host-query messages.

router

Disables or enables MLD or IGMP membership tracking.

show mld nsf

To display the state of the nonstop forwarding (NSF) operation in Multicast Listener Discovery (MLD), use the show mld nsf command in EXEC mode.

show mld [old-output] [ vrf vrf-name ] nsf

Syntax Description

old-output

(Optional) Displays the old show output—available for backward compatibility.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The show mld nsf command displays the current multicast NSF state for MLD. The NSF state that is displayed may be either normal or activated for NSF. The activated state indicates that recovery is in progress due to an MLD failure. The total NSF timeout and time remaining are displayed until NSF expiration.

Task ID

Task ID

Operations

multicast

read

Examples

The following is sample output from the show mld nsf command:

RP/0/0/CPU0:router# show mld nsf 

IP MLD Non-Stop Forwarding Status:
Multicast routing state: Non-Stop Forwarding Activated
NSF Lifetime: 00:01:00
NSF Time Remaining: 00:00:06

Table 1 describes the significant fields shown in the display.

Related Commands

Command

Description

nsf (multicast)

Enables NSF capability for the multicast routing system.

nsf lifetime (IGMP/MLD)

Configures the NSF timeout value for the IGMP or MLD process.

nsf lifetime (PIM)

Configures the NSF timeout value for the PIM process.

show mfib nsf

Displays the state of NSF operation for the MFIB line cards.

show mrib nsf

Displays the state of NSF operation in the MRIB.

show pim nsf

Displays the state of NSF operation for PIM.

show mld ssm map

To display the source-specific mapping (SSM) state in Multicast Listener Discovery (MLD), use the show mld ssm map command in EXEC mode.

show mld [ vrf vrf-name ] ssm map [group-address] [detail]

Syntax Description

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

group-address

(Optional) Address of the SSM group for which to obtain the mapping state.

detail

(Optional) Displays detailed source information.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.7.0

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

Task ID

Task ID

Operations

multicast

read

Examples

The following example illustrates the use of the show mld ssm map command:

RP/0/0/CPU0:router# show mld ssm map 2001:0DB8::/48


2001:0DB8::/48 is static with 1 source

show mld summary

To display group membership information for Multicast Listener Discovery (MLD), use the show mld summary command in EXEC mode.

show mld [old-output] [ vrf vrf-name ] summary

Syntax Description

old-output

(Optional) Displays the old show output—available for backward compatibility.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The show mld summary command is used to display the total group membership. The value for number of groups is the total number of group members on all interfaces. The value for maximum number of groups is the total number of external and local members possible for all interfaces. The maximum number of groups and the default value for the maximum number of groups is 50000 members. The maximum number of groups for each interface, and the default value for the maximum number of groups for each interface, is 25000 members.

Task ID

Task ID

Operations

multicast

read

Examples

The following example shows the number of groups for each interface that are MLD members and the maximum number of groups that can become members on each interface:

RP/0/0/CPU0:router# show mld summary

MLD summary

Robustness Value 2
No. of Group x Interfaces 39
Maximum number of Group x Interfaces 4500

Supported Interfaces   : 12
Unsupported Interfaces : 1
Enabled Interfaces     : 2
Disabled Interfaces    : 3

Interface                 Grp No    Max Grp No
Loopback0                 11        25000 
Loopback1                 10        25000 
Loopback2                 9         25000 
Loopback3                 9         25000 

Table 1 describes the significant fields shown in the display.

Related Commands

Command

Description

show mld groups

Displays the multicast groups that are directly connected to the router and that were learned through Multicast Listener Discovery (MLD).  

show mld traffic

To display all the Multicast Listener Discovery (MLD) traffic-related counters, use the show mld traffic command in EXEC mode.

show mld [old-output] [ vrf vrf-name ] traffic

Syntax Description

old-output

(Optional) Displays the old show output—available for backward compatibility.

vrf vrf-name

(Optional) Specifies a VPN routing and forwarding (VRF) instance.

Command Default

No default behavior or values

Command Modes

EXEC

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

The vrf vrf-name keyword and argument were added.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

The show mld traffic command is used to display the state of all counters for MLD traffic. It gives information about the length of time the counters have been active and the count of different types of MLD packets received, such as queries, leaves, and reports. Also, this command keeps a count of all the erroneous MLD packets received.

Task ID

Task ID

Operations

multicast

read

Examples

The following is sample output from the show mld traffic command:

RP/0/0/CPU0:router# show mld traffic 

MLD Traffic Counters
Elapsed time since counters cleared: 15:27:38

                                  Received        Sent
Valid MLD Packet                       10          10
Queries                                 2           2
Reports                                 8           8
Leaves                                  0           0
Mtrace packets                          0           0
DVMRP packets                           0           0
PIM packets                             0           0

Errors:
Malformed Packets                                  0
Bad Checksums                                      0
Socket Errors                                      0
Bad Scope Errors                                   0
Auxiliary Data Len Errors                          0
Subnet Errors                                      0
Packets dropped due to invalid socket              0
Packets which couldn't be accessed                 0
Other packets drops                                0

Table 1 describes the significant fields shown in the display.

Related Commands

Command

Description

show pim traffic

Displays PIM traffic counter information.

ssm map static

To map group memberships from legacy hosts in Source-Specific Multicast (SSM) groups accepted by an access control list (ACL) to a Protocol Independent Multicast (PIM)-SSM source, use the ssm map static command in the appropriate configuration mode. To revert to default behavior, use the no form of this command.

ssm map static source-address access-list

no ssm map static source-address access-list

Syntax Description

source-address

PIM-SSM source address to be used to create a static mapping.

access-list

ACL specifying the groups to be used to create a static mapping.

Command Default

Legacy host membership reports in the SSM group range are discarded.

Command Modes

IGMP VRF configuration

MLD configuration

Command History

Release

Modification

Release 3.7.0

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

PIM-SSM requires the use of IGMPv3 (IPv4) or MLD (IPv6) to determine local memberships. Under normal operating conditions, IGMP and MLD discard older version group membership reports for groups in the SSM group range. This means that a host with a legacy group membership protocol is unable to receive data from a PIM-SSM source.

The ssm map static command maps an older group membership report to a set of PIM-SSM sources. If the ACL associated with a configured source accepts the SSM group, then that source is included in its set of sources for the SSM group.

Task ID

Task ID

Operations

multicast

read, write

Examples

The following example shows PIM-SSM mapping in IGMP routing configuration mode:

RP/0/0/CPU0:router(config)# configuration
RP/0/0/CPU0:router(config)# router igmp
RP/0/0/CPU0:router(config-igmp)# ssm map static 10.0.0.1 mc2 
RP/0/0/CPU0:router(config-igmp)#

static-group

To configure the router to be a statically configured member of the specified group on the interface, or to statically forward for a multicast group onto the interface, use the static-group command in the appropriate configuration mode. To return to the default behavior, use the no form of this command.

static-group group-address [ inc-mask mask count cnt ] [ source-address [ inc-mask mask count cnt ] ]

no static-group group-address [ inc-mask mask count cnt ] [ source-address [ inc-mask mask count cnt ] ]

Syntax Description

group-address

IP address of the multicast group in either IPv4 or IPv6 prefixing format:


  • IP address as defined in the Domain Name System (DNS) hosts table or with the domain IPv4 host in the format A.B.C.D .
  • IP address as defined in the Domain Name System (DNS) hosts table or with the domain IPv6 host in the form of X:X::X .

inc-mask mask

(Optional) Specifies a mask for the increment range. This is an IP address expressed range in either IPv4 or IPv6 prefixing format. This mask is used with the group address to generate subsequent group addresses:


  • IP address as defined in the Domain Name System (DNS) hosts table or with the domain IPv4 host in the format A.B.C.D .
  • IP address as defined in the Domain Name System (DNS) hosts table or with the domain IPv6 host in the form of X:X::X .
Note   

This mask is used with the group address to generate subsequent group addresses.

count cnt

(Optional) Specifies a number of group addresses to generate using the increment mask. Range is 1 to 512.

source address

(Optional) Source address of the multicast group to include in either IPv4 or IPv6 prefixing format:


  • IP address as defined in the Domain Name System (DNS) hosts table or with the domain IPv4 host in the format A.B.C.D .
  • IP address as defined in the Domain Name System (DNS) hosts table or with the domain IPv6 host in the form of X:X::X .

Command Default

A router is not a statically connected member of an IP multicast group.

Command Modes

IGMP interface configuration

MLD interface configuration

Command History

Release

Modification

Release 3.3.0

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

When you configure the static-group command, packets to the group are switched out the interface, provided that packets were received on the correct Reverse Path Forwarding (RPF) interface.

The static-group command differs from the join-group command. The join-group command allows the router to join the multicast group and draw traffic to an IP client process (that is, the route processor). If you configure both the join-group and static-group command for the same group address, the join-group command takes precedence and the group behaves like a locally joined group.


Note


The static-group command has no impact on system performance.


Task ID

Task ID

Operations

multicast

read, write

Examples

In the following example, the router statically joins two multicast groups 225.2.2.2 and 225.2.2.4 for the specific source 1.1.1.1:

RP/0/0/CPU0:router(config)# router igmp
RP/0/0/CPU0:router(config-igmp)# interface GigE 0/1/0/0
RP/0/0/CPU0:router(config-igmp-default-if)# static-group 225.2.2.2 inc-mask 0.0.0.2 count 2 1.1.1.1

version

To configure an Internet Group Management Protocol (IGMP) or Multicast Listener Discovery (MLD) version for the router, use the version command in the appropriate configuration mode. To restore the default value, use the no form of this command.

version { 1 | 2 | 3 }

no version

Syntax Description

1

Specifies IGMP Version 1. Available for IGMP and MLD.

2

Specifies IGMP Version 2. Available for IGMP and MLD.

3

Specifies IGMP Version 3. Available for IGMP only.

Command Default

If this command is not specified in interface configuration mode, the interface adopts the IGMP or MLD version parameter specified in IGMP VRF configuration mode.

If this command is not specified in IGMP or MLD configuration mode, IGMP uses Version 3 and MLD uses Version 1.

Command Modes

IGMP configuration

IGMP VRF configuration

IGMP interface configuration

MLD configuration

MLD VRF configuration

MLD interface configuration

Command History

Release

Modification

Release 3.2

This command was introduced.

Release 3.5.0

This command was supported in the following configuration modes:


  • IGMP interface configuration
  • MLD interface configuration

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

All routers on the subnet must be configured with the same version of IGMP or MLD. For example, a router running Cisco IOS XR software does not automatically detect Version 1 systems and switch to Version 1. Hosts can have any IGMP or MLD version and the router will correctly detect their presence and query them appropriately.

The query-max-response-time and query-timeout commands require IGMP Version 2 or 3 or MLD Version 1 or 2.


Note


If you configure this command in IGMP or MLD configuration mode, parameters are inherited by all new and existing interfaces. You can override these parameters on individual interfaces from interface configuration mode.


Task ID

Task ID

Operations

multicast

read, write

Examples

The following example shows how to configure the router to use IGMP Version 3:

RP/0/0/CPU0:router(config)# router igmp 
RP/0/0/CPU0:router(config-igmp)# version 3

Related Commands

Command

Description

query-max-response-time

Configures the maximum response time advertised in Internet Group Management Protocol (IGMP) or Multicast Listener Discovery (MLD) queries.  

query-timeout

Configures the timeout value before the router takes over as the querier for the interface.  

vrf (igmp)

To configure a virtual private network (VRF) instance, use the vrf command in IGMP routing configuration and MLD routing configuration mode. To remove the VRF instance from the configuration file and restore the system to its default condition, use the no form of this command.

vrf vrf-name

no vrf vrf-name

Syntax Description

vrf-name

Name of the VRF instance.

Command Default

No default behavior or values

Command Modes

IGMP configuration

MLD configuration

Command History

Release

Modification

Release 3.7.0

This command was introduced.

Usage Guidelines

To use this command, you must be in a user group associated with a task group that includes the proper task IDs. If you suspect user group assignment is preventing you from using a command, contact your AAA administrator for assistance.

When you use the vrf command from the IGMP routing configuration mode to configure a VRF instance, you enter the IGMP VRF configuration submode. Likewise, when you use the vrf command from the MLD routing configuration mode, you enter MLD VRF configuration submode.

A VRF instance is a collection of VPN routing and forwarding tables maintained at the provider edge (PE) router.


Note


Although the vrf command is available in MLD routing configuration submode, MLD does not support virtual routing and forwarding. Its function there is simply to allow both routing protocols to share the same configuration code.


Task ID

Task ID

Operations

multicast

read, write

Examples

The following example shows how to configure a VRF instance in IGMP configuration submode and to enter VRF configuration submode:

RP/0/0/CPU0:router(config)# router igmp
RP/0/0/CPU0:router(config-igmp)# vrf 
vrf_1
RP/0/0/CPU0:router(config-igmp-vrf_1)#