DELL PC7024 User Manual

IGMP Snooping Commands

ip igmp snooping 

vlan-id

IGMP snooping is disabled on VLAN interfaces by default.

VLAN Configuration mode

This command has no user guidelines.

The following example enables IGMP snooping on VLAN 2.

console#vlan database 

console(config-vlan)#ip igmp snooping 2

This command enables or disables IGMP Snooping fast-leave mode on a 

selected VLAN. Enabling fast-leave allows the switch to immediately remove 

the layer 2 LAN interface from its forwarding table entry upon receiving an 

IGMP leave message for that multicast group without first sending out MAC-

based general queries to the interface. The no form of this command disables 

IGMP Snooping fast-leave mode on a VLAN.
You should enable fast-leave admin mode only on VLANs where only one host 

is connected to each layer 2 LAN port. This setting prevents the inadvertent 

dropping of the other hosts that were connected to the same layer 2 LAN port 

but were still interested in receiving multicast traffic directed to that group. 

Also, fast-leave processing is supported only with IGMP version 2 hosts.

ip igmp snooping fast-leave 

vlan-id

2CSPC4.XCT-SWUM2XX1.book  Page 488  Monday, October 3, 2011  11:05 AM