Re: Auto-RP Listener

Hi Sara!

Once you enable multicast routing and configure your interfaces for PIM
sparse-mode, the router starts listening on 224.0.1.40. In this way it will
learn the RP mappings but I don't think it will forward without the "ip pim
autorp listener" command.

I'm running this on a 7200 running 12.2(33)SRE

If I enable multicast and PIM sparse-mode I see what you see

R1(config)#ip multicast-routing
R1(config)#int lo0
R1(config-if)#ip pim sparse-mode

R1(config)#do sh ip pim autorp
AutoRP Information:
  AutoRP is enabled.
  RP Discovery packet MTU is 0.
  224.0.1.40 is joined on Loopback0.

PIM AutoRP Statistics: Sent/Received
  RP Announce: 0/0, RP Discovery: 0/0

However I don't see that "AutoRP groups over sparse mode interface is
enabled" until I run the "ip pim autorp listener" command

R1(config)#ip pim autorp list
R1(config)#
R1(config)#do sh ip pim autorp
AutoRP Information:
  AutoRP is enabled.
  RP Discovery packet MTU is 0.
  224.0.1.40 is joined on Loopback0.
  AutoRP groups over sparse mode interface is enabled

PIM AutoRP Statistics: Sent/Received
  RP Announce: 0/0, RP Discovery: 0/0

I see why it's confusing but the show command is just misleading.

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Received on Thu Jan 31 2013 - 17:15:13 ART