Quick Reference Guide

PowerConnect B-Series TI24X Configuration Guide 449
53-1002269-02
Configuring IGMP snooping
18
PowerConnect(config-vlan-20)# multicast disable-multicast-snoop
Syntax: [no] multicast disable-multicast-snoop
Disabling transmission and receipt of IGMP packets
on a port
When a VLAN is snooping-enabled, all IGMP packets are trapped to the CPU without hardware
VLAN flooding. The CPU can block IGMP packets to and from a multicast-disabled port, and does
not add it to the output interfaces of hardware resources. This prevents the disabled port from
receiving multicast traffic. However, if static groups to the entire VLAN are defined, the traffic from
these groups is VLAN flooded, including to disabled ports. Traffic from disabled ports cannot be
blocked in hardware, and is switched in the same way as traffic from enabled ports.
This command has no effect on a VLAN that is not snooping-enabled because all multicast traffic is
VLAN flooded.
To disable transmission and receipt of IGMP packets on a port, enter commands such as the
following.
PowerConnect(config)# interface ethernet 3
PowerConnect(config-if-e10000-3)# ip-multicast-disable
The above commands disable IGMP snooping on port 3 but does not affect the state of IGMP on
other ports.
Syntax: [no] ip-multicast-disable
Modifying the age interval for group membership entries
When the device receives a group membership report, it makes an entry for that group in the IGMP
group table. The age interval specifies how long the entry can remain in the table before the device
receives another group membership report. When multiple devices connect together, all devices
should be configured for the same age interval, which should be at least twice the length of the
query interval, so that missing one report won't stop traffic. Non-querier age intervals should be the
same as the age interval of the querier.
To modify the age interval, enter a command such as the following.
PowerConnect(config)# ip multicast age-interval 280
Syntax: [no] ip multicast age-interval <interval>
The <interval> parameter specifies the aging time. You can specify a value from 20 - 7200
seconds. The default is 260 seconds.
Modifying the query interval (active IGMP snooping
mode only)
If IP multicast traffic reduction is set to active mode, you can modify the query interval to specify
how often the device sends group membership queries. When multiple queriers connect together,
they should all be configured with the same query interval.
To modify the query interval, enter a command such as the following.
PowerConnect(config)# ip multicast query-interval 120