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Forum Replies

  1. Hi Hamood,

    There’s a big difference between using _ or $.

    The _ matches on the white space between two AS numbers, the $ means that it’s the end of the string. If you would use ^10886$ then you are only matching an AS path that only has 10886 in it and nothing else.

    It’s a good exercise to try this on a looking glass server :slight_smile:


  2. Hi Mario,

    The [0-9] means any number between 0 and 9, this means 0,1,2,3,4,5,6,7,8 and 9 are valid. The * means that we repeat the previous number 0 or multiple times. Basically this means any number from 0 to infinity matches. In our example we have 16 bit AS numbers so that means any AS number from 0 to 65535 will be matched.

    The + is similar to the * but it means that we repeat the previous number 1 or multiple times. In practice, there’s a big difference between the two…for example:

    When I use ^3257_[0-9]*$ then I’m matching everything that starts with AS 3

    ... Continue reading in our forum

  3. Hi @cradlepoint,

    It is possible to mix route-maps, filter-lists, distribute-lists etc. but it’s better to stick to a single route-map.

    The route-map can do everything you want and it allows you to keep everything in one place. If you want to match on an AS path and set the local preference for those routes, you can do something like this:

    ip as-path access-list 1
     permit ^46435_[0-9]*$
    route-map filter-and-local-pref permit 10
      match as-path 1
     set local-preference 200
    neighbor x.x.x.x route-map filter-and-local-pref in

    Without the empty permit 20 stateme

    ... Continue reading in our forum

  4. Hello Chris

    The command show ip as-path access-list displays information about IP AS path access lists.

    I hope this has been helpful!


  5. Hello

    please If I have below configuration , what does it do?

    route-map CC-IN, deny, sequence 2
      Match clauses:
        as-path (as-path filter): 15 
      Set clauses:
      Policy routing matches: 0 packets, 0 bytes
    show ip as-path-access-list 15
    AS path access list 15
         permit ^39216$
      neighbor route-map CC-IN in

    thanks for your support.

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