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Forum Replies

  1. Hi, Rene.

    I’m replicating this same scenario in GNS3 and even applying the filters to some specific routes, I lose all routes from the routing table and in the BGP table. Why is this so?

  2. Hi @stlourenco,

    It is difficult to tell without seeing your prefix-list or the configuration. There might be an error in your prefix-list or you refer to the wrong one in your BGP configuration (which will deny everything).

  3. Hi Rene,

    can you explain the reason that the result of “show ip bgp” on R1 is giving the symbol ‘r’ beside the received prefixes from R2?

    R1#show ip bgp 
    BGP table version is 4, local router ID is
    Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
                  r RIB-failure, S Stale, m multipath, b backup-path, x best-external, f RT-Filter
    Origin codes: i - IGP, e - EGP, ? - incomplete
       Network          Next Hop            Metric LocPrf Weight Path
    r>             0             0 2 i
    ... Continue reading in our forum

  4. Hi Walid,

    I just labbed this up again and I’m getting the same RIB failures. If you enable a debug, you can see the reason:

    R1#debug ip routing 
    IP routing debugging is on

    This shows up when you clear the routing table or clear the BGP neighbor adjacency:

    RT: rib validate nexthop return code: 3
    RT: rib validate nexthop return code: 3
    RT: rib validate nexthop return code: 3

    Return code 3 means the prefix is filtered because of an access-list. This one got me scratching my head for a bit…

    The weird thing is, the access-list seems to be correct. They use the exa

    ... Continue reading in our forum

  5. Hi Dmitriy,

    You are correct, this is a type. A wildcard of means the last six bits match and we ignore the first two bits.

    Thanks! Just fixed this.


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