Enabling Igmp Immediate-Leave Processing; Displaying Igmp Snooping Information - Cisco WS-C3550-12G Software Configuration Manual

Chapter 11 Configuring IGMP Snooping and MVR

Enabling IGMP Immediate-Leave Processing

When you enable IGMP Immediate-Leave processing, the switch immediately removes a port when it
detects an IGMP version 2 leave message on that port. You should use the Immediate-Leave feature only
when there is a single receiver present on every port in the VLAN.
Immediate Leave is supported with only IGMP version 2 hosts.
Beginning in privileged EXEC mode, follow these steps to enable IGMP Immediate-Leave processing:
Command
Step 1 configure terminal
Step 2
ip igmp snooping vlan vlan-id
immediate-leave
Step 3
end
Step 4 show ip igmp snooping vlan vlan-id
Step 5 copy running-config startup-config
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 processing on VLAN 130 and verify the
configuration:
Switch# configure terminal
Switch(config)# ip igmp snooping vlan 130 immediate-leave
Switch(config)# end
Switch# show ip igmp snooping vlan 130
vlan 130
----------
IGMP snooping is globally enabled
IGMP snooping is enabled on this Vlan
IGMP snooping immediate-leave is enabled on this Vlan
IGMP snooping mrouter learn mode is pim-dvmrp on this Vlan
IGMP snooping is running in IGMP_ONLY mode on this Vlan

Displaying IGMP Snooping Information

You can display IGMP snooping information for dynamically learned and statically configured router
ports and VLAN interfaces. You can also display MAC address multicast entries for a VLAN configured
for IGMP snooping.
To display IGMP snooping information, use one or more of the privileged EXEC commands in
Table
78-11194-03
Purpose
Enter global configuration mode
Enable IGMP Immediate-Leave processing on the VLAN interface.
Return to privileged EXEC mode.
Verify that Immediate Leave is enabled on the VLAN.
(Optional) Save your entries in the configuration file.
11-4.
Catalyst 3550 Multilayer Switch Software Configuration Guide
Displaying IGMP Snooping Information
11-9