Auto-RP is gone from IPv6, so the two remaining methods to establish a multicast domain’s Rendezvous Point(s) are static assignment and BSR. We will see later that with IPv6 we also have te option of embedding the RP address within the Multicast Group address.

R2(config)# ipv6 multicast-routing
R2(config)# ipv6 pim rp-address 2002:222::2

You would need to statically assign the RP on all PIM routers in the domain if going the static route. To ease that burden, let’s look at BSR for IPv6.

PIMv6 RP and BSR are very similar to their IPv4 counterparts. However, there are a number of small configuration differences.

  • The command to configure a router to announce itself as an RP via the BSR protocol is ipv6 pim bsr candidate rp <IPv6 address> - with IPv4 you specify the interface name not the address
  • The command to configure a router to start distributing RP bootstrap information and participate in BSR elections is ipv6 pim bsr candidate bsr <IPv6 Address>
  • One additional feature of an IPv6 BSR is that you may statically program a BSR with a list of candidate RPs by using the command ipv6 pim bsr announced rp <IPv6 Address> and therefore eliminate the need for dynamic RP advertisements by the candidates.

In order to make BSR operational, we need at least 1 candidate BSR router and at least 1 candidate RP router, though for fault tolerance we really need 2 of each.

As a review of the purpose of BSR, there will be an election among candidate BSRs to become the BSR for the domain. Election is based on highest priority. The winning BSR then has the responsibility of letting the rest of the network know which devices are the RPs. All of this is done through PIM messages. To establish a router as a BSR candidate use the following:

R2(config)# ipv6 pim bsr candidate bsr 2002:222::2 priority 2

If you need to see the elction results use the following.

R2#show ipv6 pim bsr election
PIMv2 BSR information

BSR Election Information
  Scope Range List: ff00::/8
  This system is the Bootstrap Router (BSR)
     BSR Address: 2002:2222::2
     Uptime: 00:01:13, BSR Priority: 2, Hash mask length: 126
     RPF: FE80::C002:13FF:FE08:0,Loopback0
     BS Timer: 00:00:46
  This system is candidate BSR
      Candidate BSR address: 2002:2222::2, priority: 2, hash mask length: 126

Now we see the configuration on how to establish a router as a candidate RP:

R1(config)#ipv6 pim bsr candidate rp 2002:1111::1 priority 2

Immediately a tunnel is built between the elected RP and the BSR, which can be viewed with show ipv6 pim tunnel .