Configuring Multicast Protocols

Context

After multicast VPN is configured on PE devices, you need to enable multicast routing on the entire network and deploy Protocol Independent Multicast (PIM) and Internet Group Management Protocol (IGMP).

All interfaces belonging to a VPN must run the same PIM mode. On a PE, interfaces in the public network instance and a VPN instance can run different PIM modes.
If multicast services have been deployed on the public network, you do not need to configure multicast protocols on the P devices and the public network interfaces on PE devices.

Procedure

Configure multicast routing.
Ensure that multicast routing has been enabled using the multicast routing-enable command on CE, P, and P devices, as well as devices at VPN sites that need to forward multicast data packets.

Configure the PIM protocol.

The PIM protocol needs to be configured for both the private and public networks.

For the private network, configure PIM for devices at VPN sites, CE devices, and VPN interfaces on PE devices.

**Table 1** PIM configuration for the private network
PIM Protocol Type	Mandatory Configuration
PIM-DM	Enable PIM-DM for interfaces at the sites, on the CE devices, in the VPN instances, and the interfaces used for establishing IBGP neighbor relationships.
PIM-SM	Configure the rendezvous point (RP): To configure a static RP, configure the same static RP address on all VPN multicast devices. To use dynamic RP, configure appropriate C-BSRs and C-RPs. Enable PIM-SM: Enable PIM-SM for the interfaces at the sites, on the CE devices, in the VPN instances, and the interfaces used for establishing IBGP neighbor relationships.

For the public network, configure PIM for the P devices and the public network interface on PE devices. If the multicast service has been deployed on the public network before the multicast VPN deployment, skip this step. Generally, the public network runs PIM-SM and uses dynamic RP.

**Table 2** PIM configuration for the public network
PIM Protocol Type	Mandatory Configuration
PIM-DM	Enable PIM-DM for interfaces on the P devices and in the public network instance on PE devices.
PIM-SM	Configure the RP: To configure a static RP, configure the same static RP address for the PE and P devices. To use dynamic RP, configure appropriate C-BSRs and C-RPs. Generally, dynamic RP is used on the public network. Enable PIM-SM: Enable PIM-SM for the interfaces on the P devices and the public network instance on PE devices.

For details about the PIM configuration, see IPv4 PIM Configuration.

Configure IGMP.
Run the igmp enable command to enable IGMP on the interfaces connected to receivers at all VPN sites. For details about the IGMP configuration, see IGMP Configuration.