Cisco WS-C2950-24 Software Configuration Guide - Page 184

Controlling IP Multicast Packets through CGMP Chapter 6 Configuring the System Changing the CGMP Router Hold-Time The router hold-time is the number of seconds the switch waits before removing (aging) a router entry and ceasing to exchange messages with the router. If it is the last router entry in a VLAN, all CGMP groups on that VLAN are removed. You can thus enter a lower router hold-time to accelerate the removal of CGMP groups. Note You can remove router ports before the router hold-time has expired. Beginning in privileged EXEC mode, follow these steps to change the router hold-time. Step 1 Step 2 Command configure terminal cgmp holdtime 400 Step 3 end Step 4 show running-config Purpose Enter global configuration mode. Configure the number of seconds the switch waits before dropping a router entry. Return to privileged EXEC mode. Verify your entry. Removing Multicast Groups You can reduce the forwarding of IP multicast packets by removing groups from the Current Multicast Groups table. Each entry in the table consists of the VLAN, IGMP multicast address, and ports. You can use the CLI to clear all CGMP groups, all CGMP groups in a VLAN, or all routers, their ports, and their expiration times. Beginning in privileged EXEC mode, follow these steps to remove all multicast groups. Step 1 Step 2 Command clear cgmp group show cgmp Purpose Clear all CGMP groups on all VLANs on the switch. Verify your entry by displaying CGMP information. 6-48 Catalyst 2900 Series XL and Catalyst 3500 Series XL Software Configuration Guide 78-6511-05