Auto-Rp - Cisco Nexus 7000 Series Configuration Manual

Configuring PIM and PIM6

Auto-RP

In the RP selection process, the RP address with the best priority is determined by the software. If the priorities
match for two or more RP addresses, the software may use the RP hash in the selection process. Only one RP
address is assigned to a group.
By default, routers are not enabled to listen or forward BSR messages. You must enable the BSR listening
and forwarding feature so that the BSR mechanism can dynamically inform all routers in the PIM domain of
the RP set assigned to multicast group ranges.
For more information about bootstrap routers, see RFC 5059.
Note The BSR mechanism is a nonproprietary method of defining RPs that can be used with third-party routers.
For information about configuring BSRs and candidate RPs, see Configuring BSRs.
Auto-RP
Auto-RP is a Cisco protocol that was prior to the Internet standard bootstrap router mechanism. You configure
Auto-RP by selecting candidate mapping agents and RPs. Candidate RPs send their supported group range
in RP-Announce messages to the Cisco RP-Announce multicast group 224.0.1.39. An Auto-RP mapping
agent listens for RP-Announce messages from candidate RPs and forms a Group-to-RP mapping table. The
mapping agent multicasts the Group-to-RP mapping table in RP-Discovery messages to the Cisco RP-Discovery
multicast group 224.0.1.40.
Caution Do not configure both Auto-RP and BSR protocols in the same network.
This figure shows the Auto-RP mechanism. Periodically, the RP mapping agent multicasts the RP information
that it receives to the Cisco-RP-Discovery group 224.0.1.40 (shown by the solid lines in the figure).
Cisco Nexus 7000 Series NX-OS Multicast Routing Configuration Guide
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