Configuring Rgmp On The Msfc; Displaying The Multicast Protocol Status; Understanding How Bidirectional Pim Works - Cisco WS-C6506 Software Manual

Chapter 51 Configuring Multicast Services

Configuring RGMP on the MSFC

To configure RGMP on a VLAN interface on the MSFC, perform this task:
Task
Step 1
Access VLAN interface configuration mode.
Step 2
Enable RGMP.
You can use the debug ip rgmp command to monitor RGMP on the MSFC.

Displaying the Multicast Protocol Status

This command displays the status (enabled or disabled) of the Layer 2 multicast protocols on the switch.
To display the multicast protocol status, perform this task in privileged mode:
Task
Display the multicast protocol status.
This example shows how to display the multicast protocol status:
Console> (enable) show multicast protocols status
IGMP enabled
IGMP fastleave disabled
IGMP V3 processing disabled
IGMP V3 fastblock feature disabled
RGMP disabled
GMRP disabled
Console> (enable)

Understanding How Bidirectional PIM Works

Supervisor Engine 720 supports the hardware forwarding of the bidirectional Protocol Independent
Multicast (PIM) groups. To support the bidirectional PIM groups, Supervisor Engine 720 implements a
new mode called designated forwarder (DF) mode. The designated forwarder is the router that is elected to
forward the packets to and from a segment for a bidirectional PIM group. In DF mode, the supervisor engine
accepts the packets from the reverse path forwarding (RPF) interface and from the DF interface.
When the supervisor engine is forwarding the bidirectional PIM groups, the RPF interface is always
included in the outgoing interface list of (*,G) entry, and the DF interfaces are included depending on
IGMP/PIM joins.
If the route to the RP becomes unavailable, the group is changed to dense mode. If the RPF link to the
RP becomes unavailable, the bidirectional flow is removed from the hardware FIB.
OL-8978-04
Command
Router(config)# interface vlan vlan_ID
Router(config-if)# ip rgmp
Command
show multicast protocols status
Catalyst 6500 Series Switch Software Configuration Guide—Release 8.7
Displaying the Multicast Protocol Status
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