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Forum Replies

  1. Hi Daniel,

    I might write a short tutorial on it with an example but it is a simple one. A BGP router will prefer routes that it installed into BGP itself over a route that another router installed in BGP.


  2. Before applying AS Path prepending to one side the tie breaker was the router ID?

    if both routers Jim and John have the Same Loopback0 then isn’t the router ID the same also.

  3. Thanks a lot for the explanation Rene.

    I would like you to clarify one more thing.

    For the LAN segment: : R1 is the active router to reach and R2 is the standby as the priority for R1 is 150.

    I am not using interface for tracking as i want the failover to happen on the basis of reachability of

    I have set a tracking object with IP SLA1 for type: echo to ping and mapped it with Standby 1 on R1 to decrement priority by 90 if the ping fails.

    To verify this, I did a “Shut” on the interface of R1 connecting to R3, what happened

    ... Continue reading in our forum

  4. Shivam,
    The easiest fix for this is to include the option of “source-interface” when creating your ip sla object.

    For example:

    ip sla 1
     icmp-echo source-interface Serial0/0

    This way, even though R1 learns about via R2, it can no longer use the Serial0/0 interface to get there, so the track object will fail.


  5. Hello Chris

    BGP will choose the router ID based first on if the router-id command is present. It is not in this case. Secondly, it will choose the highest IPv4 IP address of a loopback interface. You are correct, that both R1 and R3 have the same loopback address (seen in the configs), and thus would be advertising the same router-id. So the next step would be to determine the lowest neighbour IP address, which is indeed So you are correct, it does prefer but not because of the router ID but because of the lowest neighbour IP add

    ... Continue reading in our forum

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