Configure Multicast over Layer 3 VPNs

You can configure a Layer 3 VPN to support multicast traffic using the Protocol Independent Multicast (PIM) routing protocol. To support multicast, you need to configure PIM on routers within the VPN and within the service provider's network.

Each PE router configured to run multicast over Layer 3 VPNs must have a Tunnel PIC.
A Tunnel PIC is also required on the provider routers that act as rendezvous points (RPs). Tunnel PICs are also needed on all the CE routers acting as designated routers (first-hop/last-hop routers) or as RPs, just as they are in non-VPN PIM environments.

Configure the master PIM instance at the [edit protocols pim] hierarchy level on the CE and PE routers. You also need to configure a PIM instance for the Layer 3 VPN at the [edit routing-instances routing-instance-name protocols pim] hierarchy level on the PE router. This creates a PIM instance for the indicated routing instance.

For information about how to configure PIM, see the JUNOS Internet Software Configuration Guide: Multicast.

The vpn-group-address statement is unique to a Layer 3 VPN PIM configuration. You use this statement to configure the group address for the VPN in the service provider's network. This address should be unique for each VPN. It ensures that multicast traffic is transmitted only to the specified VPN.

Configure the vpn-group-address statement at the [edit routing-instances routing-instance-name protocols pim] hierarchy level:

[edit routing-instances routing-instance-name protocols]

pim {

    vpn-group-address address;

}

The rest of the Layer 3 VPN configuration for multicast is conventional and is described in other sections of this manual. Most of the specific configuration tasks needed to activate multicast in a VPN environment involve PIM. For more information about how to configure PIM and multicast in JUNOS, including an example of how to configure multicast over Layer 3 VPNs, see the JUNOS Internet Software Configuration Guide: Multicast.