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Forum Replies

  1. Hi George,

    Sure, here’s an example. We have a router that has learned some EIGRP routes on different interfaces:

    R1#show ip route eigrp 
    Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
           D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area 
           N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
           E1 - OSPF external type 1, E2 - OSPF external type 2
           i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
           ia - IS-IS inter area, * - candidate default, U - per-user static route
    ... Continue reading in our forum

  2. Mounir,
    You are right that your NET_192 access list would match and not match anything else (because of an implicit “deny” at the end of an access-list).

    Now, in order for a prefix-list to do the same thing, you must also use the prefix-list with something else, say a route-map. A prefix-list by itself will only match or not match a particular network prefix–it won’t perform an action such as permit or deny.

    Let’s start by writing the prefix list that will match only, since you are asking about this:

    (config)#ip prefix-list PL_MAT

    ... Continue reading in our forum

  3. Hi Rene,

    I have a quick question on EIGRP filtering in general. Say I have 3 routers, R1, R2, and R3 all running EIGRP and connected.

    R1 has and
    If I want to advertise only to R3 but not R2…
    From reading your lesson, I learned that I can apply a distribute-list acl in on R3 to block the advertisement of…

    Can this be done on R1 to filter outbound EIGRP advertisement of only to R3 but not R2?



  4. Hi have been working very peripherally on cisco for a few years but signed up and love your explanations. I am working through this lesson but am surprised there is not more of an “intro” to route maps somewhere on the site, seems there is a bit of assumed knowledge on this lesson…

  5. ok I’m in over my head…

    in seq 20 why is there an ge 26 when trying to limit prefix to smaller then 26? I’ll reread in the morning hopefully it will make sense then…

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