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Catalyst 2960 Switch SoftwareConfiguration Guide
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Chapter20 Configuring IGMP Snooping and MVR
Configuring IGMP Snooping
Note Immediate Leave is supported only on IGMP Version 2 hosts.
Beginning in privileged EXEC mode, follow these steps to enable IGMP Immediate Leave:
To disable IGMP Immediate Leave on a VLAN, use the no ip igmp snooping vlan vlan-id
immediate-leave global configuration command.
This example shows how to enable IGMP Immediate Leave on VLAN 130:
Switch# configure terminal
Switch(config)# ip igmp snooping vlan 130 immediate-leave
Switch(config)# end
Configuring the IGMP Leave Timer
Follows these guidelines when configuring the IGMP leave timer:
You can configure the leave time globally or on a per-VLAN basis.
Configuring the leave time on a VLAN overrides the global setting.
The default leave time is 1000 milliseconds.
The IGMP configurable leave time is only supported on hosts running IGMP Version 2.
The actual leave latency in the network is usually the configured leave time. However, the leave time
might vary around the configured time, depending on real-time CPU load conditions, network delays
and the amount of traffic sent through the interface.
Beginning in privileged EXEC mode, follow these steps to enable the IGMP configurable-leave timer:
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 ip igmp snooping vlan vlan-id
immediate-leave
Enable IGMP Immediate Leave on the VLAN interface.
Step3 end Return to privileged EXEC mode.
Step4 show ip igmp snooping vlan vlan-id Verify that Immediate Leave is enabled on the VLAN interface.
Step5 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 ip igmp snooping
last-member-query-interval time
Configure the IGMP leave timer globally. The range is 100 to 5000
milliseconds. The default is 1000 seconds.
Step3 ip igmp snooping vlan vlan-id
last-member-query-interval time
(Optional) Configure the IGMP leave time on the VLAN interface. The
range is 100 to 5000 milliseconds.
Note Configuring the leave time on a VLAN overrides the globally
configured timer.
Step4 end Return to privileged EXEC mode.