Extreme Networks ExtremeWare XOS 11.0, Command Reference Manual

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892 ExtremeWare XOS 11.0 Command Reference Guide
IP Multicast Commands
configure igmp snooping timer
configure igmp snooping timer <router_timeout> <host_timeout>
Description
Configures the IGMP snooping timers.
Syntax Description
Default
The router timeout default setting is 260 seconds. The host timeout setting is 260 seconds.
Usage Guidelines
Timers should be set to approximately 2.5 times the router query interval in use on the network. Specify
the following:
• router timeout—The interval, in seconds, between the last time the router was discovered and the
current time. The range is 10 to 2,147,483,647 seconds (68 years). The default setting is 260 seconds.
• host timeout—The interval, in seconds, between the last IGMP group report message from the host
and the current time. The range is 10 to 2,147,483,647 seconds (68 years). The default setting is 260
seconds.
IGMP snooping is a layer 2 function of the switch. It does not require multicast routing to be enabled.
The feature reduces the flooding of IP multicast traffic. On the VLAN, IGMP snooping optimizes the
usage of network bandwidth and prevents multicast traffic from being flooded to parts of the network
that do not need it. The switch does not reduce any IP multicast traffic in the local multicast domain
(224.0.0.x).
IGMP snooping is enabled by default on the switch. If you are using multicast routing, IGMP snooping
can be enabled or disabled. If IGMP snooping is disabled, all IGMP and IP multicast traffic floods
within a given VLAN. IGMP snooping expects at least one device on every VLAN to periodically
generate IGMP query messages. Without an IGMP querier, the switch eventually stops forwarding IP
multicast packets to any port, because the IGMP snooping entries will time out, based on the value
specified in
host timeout
. An optional optimization for IGMP snooping is the strict recognition of
routers only if the remote devices are running a multicast protocol.
Example
The following command configures the IGMP snooping timers:
configure igmp snooping timer 600 600
History
This command was available in ExtremeWare XOS 10.1.
router_timeout Specifies the time in seconds between router discovery.
host_timeout Specifies the time in seconds between host reports.