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Forum Replies

  1. Hi Rene,

    So I am assuming [no auto-summary] is the default on BGP? Also, is there a command to see whether auto-sum is enabled or not. When I run [show run | section bgp] there is no mention of auto-sum.


  2. Hi Mario,

    No auto-summary is the default for BGP. It’s one of those commands that doesn’t show up in the running-config because it’s default.

    I think you can see it with “show run all” though.


  3. Hi Rene,

    I have followed the same config you have explained but it’s not working at all.
    Refer to the below outputs.

    IOU1#show run int lo0
    Building configuration…

    Current configuration : 61 bytes
    interface Loopback0
    ip address

    IOU1#show run | s bgp
    router bgp 1
    bgp log-neighbor-changes
    neighbor remote-as 2
    IOU1#show ip bgp summ
    BGP router identifier, local AS number 1
    BGP table version is 1, main routing table version 1

    Neighbor V AS MsgRcvd MsgSent TblVer In

    ... Continue reading in our forum

  4. Hello Krishendu

    At first glance, i don’t see anything wrong with your configuration, but remember, there are two sides to the link. Check to see what configuration setup exists on the other BGP router. Also, try using some debugging commands such as debug ip bgp to see what is being exchanged between the routers.

    I hope this has been helpful!


  5. Hi,

    If we can advertise exact network and subnet mask so whats is the need of auto-summary command?

    What would be the reason to advertise network address without subnet mask? can you please give example of the network where have to advertise a network without subnet mask and then use auto-summary command?

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