Configuring a PIM RPF Routing Table

By default, PIM uses inet.0 as its reverse-path-forwarding (RPF) routing table group. PIM uses an RPF routing table group to resolve its RPF neighbor for a particular multicast source address and to resolve the RPF neighbor for the RP address. PIM can optionally use inet.2 as its RPF routing table group.

Specifying additional import routing table groups or an export routing table group in the routing table group has no effect on PIM operation. PIM uses the first routing table group specified as an import routing table group.

PIM uses a single routing table group as its RPF routing table group. This ensures that the route with the longest matching prefix is chosen as the RPF route.

To define a routing table group and use it to populate inet.2 for RPF checks:

To do this, configure a routing table group. You must include the export-rib statement because inet.0 cannot be the default table for exporting routes into another table with the import-rib statement.
[edit]user@host# edit routing-options rib-groupsuser@host# set pim-rg export-rib inet.0user@host# set pim-rg import-rib [ inet.0 inet.2 ]
Specify the routing table group for PIM globally or for a routing instance. This example shows the global configuration.
[edit]user@host# edit protocols pimuser@host# set rib-group pim-rg
Verify the configuration by checking the Multicast RPF table field in the output of the show multicast rpf command.

You can configure OSPF to populate inet.2 with OSPF routes that have regular IP next hops. This allows RPF to work properly even when MPLS is configured for traffic engineering, or when OSPF is configured to use “shortcuts” for local traffic.

You can also configure IS-IS to populate inet.2 with IS-IS routes that have regular IP next hops. This allows RPF to work properly even when MPLS is configured for traffic engineering, or when IS-IS is configured to use “shortcuts” for local traffic.

Configuring a PIM RPF Routing Table

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