Ip Igmp Snooping - Cisco Catalyst 3750 Command Reference Manual

ip igmp snooping

Defaults
IGMP snooping is globally enabled on the switch.
IGMP snooping is enabled on VLAN interfaces.
IGMP immediate-leave processing is disabled.
The default learning method is pim-dvmrp—to snoop IGMP queries and PIM-DVMRP packets.
By default, there are no ports specified as members of a static multicast group.
By default, there are no multicast router ports.
Command Modes
Global configuration
Command History Release
12.1(11)AX
Usage Guidelines When IGMP snooping is enabled globally, it is enabled in all the existing VLAN interfaces. When IGMP
snooping is disabled globally, it is disabled on all the existing VLAN interfaces.
You should only configure the Immediate Leave feature when there is a maximum of one receiver on
every port in the VLAN. The configuration is saved in nonvolatile RAM (NVRAM).
The Immediate Leave feature is supported only with IGMP Version 2 hosts.
The CGMP learn method is useful for reducing control traffic.
The static keyword is used for configuring the IGMP member ports statically.
The enabled configuration (globally or per VLAN), the learn method, and the static ports and groups are
saved in nonvolatile RAM (NVRAM).
Examples
This example shows how to globally enable IGMP snooping:
Switch(config)# ip igmp snooping
This example shows how to globally disable IGMP snooping:
Switch(config)# no ip igmp snooping
This example shows how to enable IGMP snooping on VLAN 1:
Switch(config)# ip igmp snooping vlan 1
This example shows how to disable IGMP snooping on VLAN 1:
Switch(config)# no ip igmp snooping vlan 1
This example shows how to enable IGMP immediate-leave processing on VLAN 1:
Switch(config)# ip igmp snooping vlan 1 immediate-leave
This example shows how to disable IGMP immediate-leave processing on VLAN 1:
Switch(config)# no ip igmp snooping vlan 1 immediate-leave
Catalyst 3750 Switch Command Reference
2-118
Modification
This command was introduced.
Chapter 2 Catalyst 3750 Switch Cisco IOS Commands
78-16181-01