Install guide

28 IGMP Enhancements Release Note
Software Version 2.7.5
C613-10454-00 REV A
IGMP Enhancements
Software Version 2.7.5 includes the following enhancements for IGMP:
■ Fast Leave
■ Filtering and Throttling
This section describes each enhancement, then the new and modified
commands in Command Reference Updates.
Fast Leave
When an IGMP group-specific leave message is received on a port, IGMP
Snooping stops the transmission of the group multicast stream after a timeout
period. The lmqi (Last Member Query Interval) and lmqc (Last Member Query
Count) parameters of the set ip igmp command set the timeout period. This
timeout period allows other hosts on the port to register their membership of
the multicast group and continue receiving the stream.
The Fast Leave feature allows IGMP Snooping to stop the transmission of a
group multicast stream from a port immediately it receives a leave message,
without waiting for the timeout period.
Use the Fast Leave feature to improve bandwidth management on ports that
are connected to a single host. Fast Leave should not be configured on a port
that has multiple hosts attached because it may adversely affect multicast
services to some hosts.
Fast Leave processing is disabled by default. To enable Fast Leave on a specific
VLAN, or all VLANs on the router or switch, use the command:
set igmpsnooping fastleave={on|yes|true}
[interface=interface]
To disable Fast Leave on a specific VLAN, or all VLANs on the router or
switch, use the command:
set igmpsnooping fastleave={off|no|false}
[interface=interface]
To display the current state of Fast Leave processing on a specific VLAN, or all
VLANs on the router or switch, use the command:
show igmpsnooping [vlan={vlan-name|1..4094}]
Command Changes
The following table summarises the new and modified commands:
Command Change
set igmpsnooping fastleave New command
show igmpsnooping New Fast Leave field