Configuring PIM Designated Router Election on Point-to-Point Links

To comply with the latest PIM drafts, enable designated router (DR) election on all PIM interfaces, including point-to-point (P2P) interfaces. (DR election is enabled by default on all other interfaces). One of the two routers might join a multicast group on its P2P link interface. The DR on that link is responsible for initiating the relevant join messages.

To enable DR election on P2P interfaces:

1. On both P2P link routers, configure the router globally or in the routing instance. This example shows the configuration for the routing instance.
   [edit]user@host# edit routing-instances PIM.master protocols pimuser@host# set dr-election-on-p2p
2. Verify the configuration by checking the State field in the output of the show pim interfaces command. The possible values for the State field are DR, NotDR, and P2P. When a P2P link interface is elected to be the DR, the interface state becomes DR instead of P2P.
3. If the show pim interfaces command continues to report the P2P state, consider running the restart routing command on both routers on the P2P link. Then recheck the state.
   [edit]user@host# run restart routing

   Caution: Do not restart a software process unless specifically asked to do so by your Juniper Networks customer support representative. Restarting a software process during normal operation of a routing platform could cause interruption of packet forwarding and loss of data.

Related Topics

• PIM Sparse Mode Overview
• Configuring Interface Priority to Become the PIM Designated Router
• show pim interfaces in the Routing Protocols and Policies Command Reference