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Forum Replies

  1. i did to change AD , it work

    when i try to change metric, and make debugging which tell me is the winner, it is still give outbound prune


    my scenario is the same as your scenario

  2. Hi Jose,

    It’s very likely to see PIM assert in dense mode since we flood everything. It’s unlikely to encounter in sparse mode but it does exist. Let me give you an example. Take a look at the “pim-sparse-assert.png” image in the attachment for the topology.

    On top, we have the RP, connected to R1/R2. At the bottom we have R3/R4 with a receiver each.

    R1/R2/R3/R4 are connected to the same multi-access segment through the switch.

    • R3 uses R1 to get to the RP.
    • R4 uses R1 to get to the RP.

    Let’s say our receivers both join group This is what happens:


    ... Continue reading in our forum

  3. I am having some issues understanding this statement -

    “Now when R1 starts streaming multicast traffic towards R2 and R3 they will both forward multicast packets to R4 resulting in duplicate traffic.”

    1. Why will R1 start streaming simultaneously towards both R2 and R3?
    2. Why will R2 and R3 both forward multicast packets towards R4?

    Can you explain this in a little more detail?

  4. Hello Rene,

    Thanks for the great explanation

    PIM DR is used in PIM-Sparsh mode while PIM ASSERT is used in PIM-DENSE mode.

    Considering PIM DR is used to find router in the same broadcast domain for join message towards RP and same DR is used to forward traffic as per RPF check.

    While with PIM ASSERT only for DENSE Mode where only need to avoid duplicate packet transmissions.

    Please confirm if my understanding is right?

  5. Hi Rene,
    Sometimes PIM DR and PIM forwrder do the same role? I meant when you told don’t confuse this 2 features I’am confuse.

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