Cisco Systems EA6500 Manual De Usuario

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. 

With Release 12.1(11b)E and later releases, when you are in configuration mode you can enter EXEC 
mode-level commands by entering the do keyword before the EXEC mode-level command.

To enable RGMP on a Layer 3 interface, perform this task:

This example shows how to configure RGMP on FastEthernet port 3/3:

Router# configure terminal 

Enter configuration commands, one per line.  End with CNTL/Z.

Router(config)# interface fastethernet 3/3 

Router(config-if)# ip rgmp 

Router(config-if)# end 

Router#

Router(config)# interface {{vlan vlan_ID} | 

{type

1

 slot/port} | {port-channel number}} 

1.

type = ethernet, fastethernet, gigabitethernet, tengigabitethernet, or ge-wan 

Selects an interface to configure. 

Router(config-if)# ip rgmp 

Enables RGMP on the Layer 3 interface. 

Router(config-if)# no ip rgmp 

Disables RGMP on the Layer 3 interface. 

Router(config-if)# end 

Exits configuration mode.

Router# debug ip rgmp [name_or_group_address] 

(Optional) Monitors RGMP.