This window is available for Catalyst 2900 XL and 3500 XL switches only. It appears when you choose Device > CGMP on the menu bar. You can also click here to launch it. Use it to:
CGMP is enabled by default. To disable CGMP:
Normally, a CGMP-enabled router does not remove a CGMP group until all members are removed from the group, but you can accelerate group removal from the switch and the router by using the CGMP Fast Leave feature.
Fast Leave is disabled by default. To enable the CGMP Fast Leave feature:
Note: The CGMP Fast Leave feature works only if CGMP is enabled. The client must be running IGMP Version 2 for the CGMP Fast Leave feature to function properly.
The router hold-time is the number of seconds the switch waits before removing a router entry. If the removed router is the last router entry on a VLAN, all groups on the VLAN are removed.
To modify the router hold-time setting:
The Management Groups tab lists each VLAN ID on which the switch is forwarding IP multicast packets, the IGMP MAC address of the router or group in the VLAN, and the switch port forwarding the multicast traffic to the group. If the CGMP Fast Leave feature is disabled, you can speed up the removal of a group (and its end stations) by removing the port entry from this tab.
To remove a management group:
Another way to speed up the removal of multicast groups is through the Router Ports table. The Router Ports table lists each VLAN ID on which the switch is forwarding IP multicast packets, the IGMP MAC address of the router port, the router expiration time, and the router port number.
When the router expiration time shown in the entry reaches 0 seconds, and if the router is the last member of the VLAN, the multicast group table is cleared.
To remove a CGMP-enabled router and all members associated with its multicast group: