TASK 5.3 BGP aggregation useing another way !!!! need confirmation

Hi guys i need to confirm that

in this task instead of useing prefix list and deny it which is right 100%


i think if i use an as path which permit ^200$


and put itin a route map

in the aggregation command i use as-set addvertise-map   with map athat has ^200$

this way AS 200 will not put the aggregated route in to its bgp routing table

is this way is correct ??


Thank you


  • But remeber that the task states that the configuration should be sone on AS100. [:O]

  • An alternative way to accomplish this task would be to configure R6 not
    to advertise the summary to R3 as well as R5. The summary would still be
    advertised to AS54 but not AS200 which is what the task specifies. It
    doesn't mention that R3 should have this summary address. I've used the
    following solution and  I think it might be an acceptable solution.


    ! r6
    conf t
    ip prefix-list SUMMARY seq 5 permit
    route-map NO_SUMMARY deny 10
     match ip add prefix-list SUMMARY
    route-map NO_SUMMARY permit 20
    router bgp 100
     aggregate-address summary-only
     neighbor route-map NO_SUMMARY out
     neighbor route-map NO_SUMMARY out


    RSRack1R3#sh ip bgp
    % Network not in table

    RSRack1R5#sh ip bgp
    % Network not in table

    RSRack1R6#sh ip bgp nei adver
    BGP table version is 14, local router ID is
    Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
                  r RIB-failure, S Stale
    Origin codes: i - IGP, e - EGP, ? - incomplete

       Network          Next Hop            Metric LocPrf Weight Path
    *>                            32768 i

    Total number of prefixes 1

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