Enabling multicast data encapsulation in SA messages

Some multicast sources send multicast data at an interval longer than the aging time of (S, G) entries. In this case, the source-side DR must encapsulate multicast data packet-by-packet in register messages and send them to the source-side RP. The source-side RP transmits the (S, G) information to the remote RP through SA messages. Then, the remote RP sends join messages to the source-side DR and builds an SPT. Because the (S, G) entries have timed out, remote receivers can never receive the multicast data from the multicast source.

To avoid this problem, you can enable the source-side RP to encapsulate multicast data in SA messages. As a result, the source-side RP can forward the multicast data in SA messages to its remote MSDP peers. After receiving the SA messages, the remote RP decapsulates the SA messages and forwards the multicast data to the receivers in the local domain along the RPT.

1. Enter system view.

   system-view

2. Enter MSDP view.

   msdp [ vpn-instance vpn-instance-name ]

3. Enable multicast data encapsulation in SA messages.

   encap-data-enable

   By default, an SA message contains only (S, G) entries, but not the multicast data.