Command Line Interface Guide

IGMP Snooping Commands 495
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.
Syntax
ip igmp snooping fast-leave vlan-id
no ip igmp snooping fast-leave
• vlan id — Number assigned to the VLAN.
Default Configuration
IGMP snooping fast-leave mode is disabled on VLANs by default.
Command Mode
VLAN Configuration mode
User Guidelines
This command has no user guidelines.
Example
The following example enables IGMP snooping fast-leave mode on VLAN 2.
console(config-vlan)#ip igmp snooping fast-leave 2
ip igmp snooping groupmembership-interval
This command sets the IGMP Group Membership Interval time on a VLAN.
The Group Membership Interval time is the amount of time in seconds that a
switch waits for a report from a particular group on a particular interface
before deleting the interface from the entry. This value must be greater than
the IGMPv3 Maximum Response time value. The range is 2 to 3600 seconds.
The no form of this command sets the IGMPv3 Group Membership Interval
time to the default value.
2CSPC4.X8100-SWUM100.book Page 495 Wednesday, August 29, 2012 6:23 PM