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Forum Replies

  1. Hello Rene

    How do you use the glass server?

  2. Hello Rene,
    I have a question and I am going to use the below topology for the question.


    Here Let's say my AS is 100 and I am connected to two different AS numbers 200 and 300. I am also getting default routes from both of them(from AS 300 and AS 200). My BGP table for default 0.0.0.0 route looks like this:

    According to the BGP table, I have 2 available routes for 0.0.0.0 and number 2 is the best route. My question is "why both of the routes have (received & used) beside them?". I thought only best route would have (received & used) beside it.

    Please shed some light on it.
    Thank you so much.

    Best Regards,
    Azm Uddin

  3. Jon says:

    Hi @azmuddincisco,

    Great question! You are right in thinking that a router running BGP will normally only share its "best" route with another BGP peer. However for its own internal it's possible the router can push both routes to the RIB and make use of IOS load balancing.

    We can check if this is the case by verifying the output of "show ip route". It would also help to also see the BGP config for the left hand router (including any "maximum-paths" value).

    Kind regards,
    Jon

  4. Hello Azm

    It may be possible that you have the neighbor soft-reconfiguration inbound command enabled on your router. According to Cisco:

    The neighbor soft-reconfiguration inbound command causes the router to store all received (inbound) routing policy updates without modification, for example, a duplicate table is stored in the memory for each peer. This method is memory-intensive and not recommended unless absolutely necessary.

    The (received and used usually indicates that the prefix from a soft-reconfiguration-enabled peer was not filtered so it is placed into the regular BGP table. But it is not necessarily the best path.

    Check your config and get back to us!

    I hope this has been helpful!

    Laz

  5. Hey Laz,
    You are absolutely correct. Just tested that in the lab and it was exactly what you said.
    EXCELLENT !!!!!!

    Without Soft -reconfiguration

    with Soft-reconfiguration

    Azm

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