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Forum Replies

  1. Lovely… Nice and neat

  2. Hi Rene,

    What if the cost of both (FastEthernet and Serial links) are the same. In this scenario, there will be ECMP towards the source. Here, there will be both the entries in the unicast routing table. Now, even if the multicast traffic comes on the serial link, RPF check will still pass, is that right?

    Thanks.

  3. Hi Parth,

    RPF will pass but not for both links. By default, the RPF check will be done for the neighbor with the highest IP address. This means that by default, ECMP multicast load balancing is disabled.

    For example, let’s say there are two routers…R1 and R2. Between R1 and R2 we use two interfaces. These interfaces have the same metric in whatever IGP we are using. Let’s say R1 has IP address 192.168.12.1 and 192.168.21.1 on these interfaces.

    R2 will then send the PIM join to the highest IP address PIM neighbor, 192.168.21.1. That’s the interface that will be

    ... Continue reading in our forum

  4. Hi Rene,

    is this correct? i think its a mistake, its should as in the output of the command 192.168.32.2 not 192.168.23.2…

    (192.168.12.1, 239.1.1.1), 00:04:42/00:02:59, flags: LT
      Incoming interface: Serial0/0, RPF nbr **192.168.32.2**, Mroute
      Outgoing interface list:
        Loopback0, Forward/Dense, 00:04:42/00:00:00
    

    See the RPF neighbor above? It now says 192.168.23.2 which is the IP address on the serial link of R2. As a result, our multicast traffic is now being accepted:

  5. Hello Samer

    You are correct. The text should read:

    See the RPF neighbor above? It now says 192.168.32.2 which is the IP address on the serial link of R2. As a result, our multicast traffic is now being accepted:

    I will let @ReneMolenaar know.

    Thanks again!

    Laz

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