Configuring PIM Embedded RP for IPv6

You configure embedded RP to allow multidomain IPv6 multicast networks to find RPs in other routing domains. Embedded RP embeds an RP address inside PIM join messages and other types of messages sent between routing domains. Global IPv6 multicast between routing domains has been possible only with source-specific multicast (SSM) because there is no way to convey information about IPv6 multicast RPs between PIM sparse mode RPs. In IPv4 multicast networks, this information is conveyed between PIM RPs using MSDP, but there is no IPv6 support in current MSDP standards. IPv6 uses the concept of an embedded RP to resolve this issue without requiring SSM. Thus, embedded RP enables you can deploy IPv6 with any-source multicast (ASM).

Embedded RP is disabled by default.

When you configure embedded RP for IPv6, embedded RPs are preferred to RPs discovered by IPv6 any other way. You configure embedded RP independent of any other IPv6 multicast properties. This feature is applied only when IPv6 multicast is properly configured.

1. Define which multicast addresses or prefixes can embed RP address information. If messages within a group range contain embedded RP information and the group range is not configured, the embedded RP in that group range is ignored. Any valid unicast-prefix-based ASM address can be used as a group range. The default group range is FF70::/12 to FFF0::/12. Messages with embedded RP information that do not match any configured group ranges are treated as normal multicast addresses.
   [edit routing-instances vpn-A protocols pim rp embedded-rp]user@host# set group-ranges fec0::/10

   If the derived RP address is not a valid IPv6 unicast address, it is treated as any other multicast group address and is not used for RP information. Verification fails if the extracted RP address is a local interface, unless the routing device is configured as an RP and the extracted RP address matches the configured RP address. Then the local RP determines whether it is configured to act as an RP for the embedded RP multicast address.

2. Limit the number of embedded RPs created in a specific routing instance. The range is from 1 through 500. The default is 100.
   [edit routing-instances vpn-A protocols pim rp]user@host# set maximum-rps 50
3. Monitor the operation by running the show pim rps and show pim statistics commands.