Multicast Auto-RP


You are a network engineer and responsible for the main network of Gotham City. Multicast will be needed to send video replays throughout the city, and to decrease network load your boss has decided that you need to implement sparse-dense-mode. The network will be fairly large, so you don’t want to configure the RP address manually on every router, let’s see if there’s an easier way…


  • All IP addresses have been preconfigured for you.
  • Configure OSPF on all routers, advertise all networks. Achieve full connectivity.
  • Configure sparse-dense-mode multicast on all routers.
  • Configure AutoRP so router Joker is the Rendezvous Point (RP), use the loopback0 interface.
  • Configure AutoRP so router Catwoman is the mapping agent (MP), use the loopback0 interface.
  • Configure router Batman to join the multicast group on it’s Fastethernet interface.
  • Make sure you can ping the group address from router Catwoman.




Multicast AUTO-RP network topology


Video Solution:

Configuration Files

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Written by René Molenaar - CCIE #41726

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About the Author: Rene Molenaar

René - CCIE #41726 is the creator of where he shares CCNA, CCNP and CCIE R&S labs. He also blogs about networking on


  1. Your final config for this has joker with the following:

    ip pim send-rp-announce Loopback0 scope 20
    ip pim send-rp-discovery Loopback0 scope 20

    If router Catwoman is to be the mapping-agent, she would need the following:
    ip pim send-rp-discovery Loopback0 scope 20

    This would need to be on Catwoman and NOT Joker. send-rp-discovery – Auto-RP send RP discovery message (as RP-mapping agent)

    With CatWoman as the RP, you should see:
    Catwoman#show ip pim rp map
    PIM Group-to-RP Mappings
    This system is an RP-mapping agent (Loopback0)

    RP (?), v2v1
    Info source: (?), elected via Auto-RP
    Uptime: 00:04:23, expires: 00:02:32

    It appears with your finalconfig Joker is both the RP and the MA.

    Your lab was helpful in nailing down some of my knowledge with auto-rp, thanks!

  2. Hello Christian,

    You are right…good job and thanks for letting me know!

    In my example Joker is indeed both the RP+MA, I should have cut/pasted this to router Catwoman:

    ip pim send-rp-discovery Loopback0 scope 20

    Glad you liked the lab though 😉


  3. Hi Rene

    the uploaded gns3 file for this lab also doesnt seem to be the right one for this lab. can you please check?


  4. I just finished the lab and it works fine except the fact that the network topology is not what u showed in the video. If you want I can mail you the modified or correct one.

    Thanks for all your help 🙂

    1. Hmmm ok let me check 🙂 If you have it please mail it to me, i’ll fix it.

      1. Could you, please, explain me, why do we need "ip pim autorp listener" commant in this lab? For me it works without of it well!

        1. Hi Serega,

          It’ because of spare-dense mode. Router need to get rp announcement from mapping agent, in order to get this,

          routers have to join Group listening to the Mapping agent. As speare-dense mode, it flood entire network as dense mode. As spare mode, that would be chicken-egg problem and you will need ‘autorp listner’

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