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Forum Replies

  1. Hi Rene,

    Thanks for your reply.
    As you mentioned, information inside the RIB is use to build the LIB.
    So i would imagine to have a LABEL for all the available routes.

    e.g. I have 3 best routes to the same destination with rip, eigrp, ospf in the RIB.  via  - rip  via  - eigrp  via  - ospf

    q1) Can i check for FIB, does it contain the same amount of available routes as in the RIB ?

    q2) if the above is yes, i would believe FLIB and FIB would have the same amount of labels ?

    q3) it is

    ... Continue reading in our forum

  2. Hi Alan,

    If OSPF, EIGRP and RIP have learned the route then only one will be installed in the routing table. EIGRP will be selected since it has the lowest administrative distance.

    By default, LDP will generate a label for each route in the routing table. This is something that you can change by using access-lists if you want.

    The LFIB has pretty much the same information as the FIB, however some entries in the FIB (like directly connected interfaces) won’t show up in the LFIB.

    Theoretically, switching based on labels is faster than routing where

    ... Continue reading in our forum

  3. Hi Stuart,

    Did you see this tutorial?


    I think that one will be helpful to understand this better. Within the MPLS “core”, we only advertise the loopback interfaces of the PE routers in our IGP, OSPF in most of my examples. The P router will only have these networks in its routing table. The LIB is based on the information of the RIB (Routing Table), so you only find labels for those loopbacks there, these are the transport labels needed to get from one PE to another PE.

    Only the PE routers have to kno

    ... Continue reading in our forum

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