44-43
Catalyst 3560 Switch Software Configuration Guide
OL-8553-06
Chapter 44 Configuring IP Multicast Routing
Configuring Optional Multicast Routing Features
To remove the switch as a member of the group, use the no ip igmp static-group group-address
interface configuration command.
Configuring Optional Multicast Routing Features
These sections describe how to configure optional multicast routing features:
Features for Layer 2 connectivity and MBONE multimedia conference session and set up:
Enabling CGMP Server Support, page 44-43 (optional)
Configuring sdr Listener Support, page 44-44 (optional)
Features that control bandwidth utilization:
Configuring an IP Multicast Boundary, page 44-45 (optional)
Procedure for configuring a multicast within a VPN routing/forwarding (VRF) table:
Configuring Multicast VRFs, page 36-76

Enabling CGMP Server Support

The switch serves as a CGMP server for devices that do not support IGMP snooping but have CGMP
client functionality. CGMP is a protocol used on Cisco routers and multilayer switches connected to
Layer 2 Catalyst switches to perform tasks similar to those performed by IGMP. CGMP is necessary
because the Layer 2 switch cannot distinguish between IP multicast data packets and IGMP report
messages, which are both at the MAC-level and are addressed to the same group address.
Beginning in privileged EXEC mode, follow these steps to enable the CGMP server on the switch
interface. This procedure is optional.
Step 4 end Return to privileged EXEC mode.
Step 5 show ip igmp interface [interface-id]Verify your entries.
Step 6 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 interface interface-id Specify the interface that is connected to the Layer 2 Catalyst switch, and
enter interface configuration mode.