Cisco WS-SUP32-GE-3B Software Configuration Guide - Page 435

Chapter 29 Configuring RGMP Enabling RGMP on Layer 3 Interfaces • The following properties of RGMP are the same as for IGMP snooping: - RGMP constrains traffic based on the multicast group, not on the sender's IP address. - If spanning tree topology changes occur in the network, the state is not flushed as it is with Cisco Group Management Protocol (CGMP). - RGMP does not constrain traffic for multicast groups 224.0.0.x (x = 0...255), which allows use of PIMv2 bootstrap router (BSR) in an RGMP-controlled network. - RGMP in Cisco network devices operates on MAC addresses, not on IP multicast addresses. Because multiple IP multicast addresses can map to one MAC address (see RFC 1112), RGMP cannot differentiate between the IP multicast groups that might map to a MAC address. - The capability of the Catalyst 6500 series switch to constrain traffic is limited by its content-addressable memory (CAM) table capacity. Enabling RGMP on Layer 3 Interfaces To enable RGMP on a Layer 3 interface, perform this task: Command Purpose Step 1 Step 2 Router(config)# interface {{vlan vlan_ID} | {type1 slot/port} | {port-channel number}} Router(config-if)# ip rgmp Selects an interface to configure. Enables RGMP on the Layer 3 interface. Router(config-if)# no ip rgmp Disables RGMP on the Layer 3 interface. Step 3 Router(config-if)# end Exits configuration mode. Step 4 Router# debug ip rgmp [name_or_group_address] (Optional) Monitors RGMP. 1. type = ethernet, fastethernet, gigabitethernet, tengigabitethernet, or ge-wan This example shows how to configure RGMP on FastEthernet port 3/3: Router# configure terminal Enter configuration commands, one per line. Router(config)# interface fastethernet 3/3 Router(config-if)# ip rgmp Router(config-if)# end Router# End with CNTL/Z. OL-11439-03 Catalyst Supervisor Engine 32 PISA Cisco IOS Software Configuration Guide, Release 12.2ZY 29-3