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Forum Replies

  1. Hello Ryan

    I notice that in your show IP route command, no EIRGP routes show up. This tells me that for some reason, no EIGRP neighbours have been created. You should at least see the and subnets separately show up. Check the neighbour table to see that they have successfully created an adjacancy. Before you configure any EIGRP summarization, try to get EIGRP alone to function correctly. Then you can add the summarization commands.

    I hope this has been helpful.


  2. andrew says:

    To check the AD of the route, issue:

    show ip route

  3. Hi ,
    Great explanation . but have one doubt can you explain below subnetting

    R1(config)#interface fastEthernet 2/0
    R1(config-if)#ip summary-address eigrp 1

    we used /24 on loopback so how did you get this mask /23 by subnetting. can you please explain

  4. We have these two networks:

    R2#show ip route eigrp  is subnetted, 2 subnets
    D [90/30720] via, 00:02:28, FastEthernet0/0
    D [90/30720] via, 00:02:28, FastEthernet0/0

    The most optimal summary rounte for and is

    In binary, these two look like this:

    • 10101100 00010000 00000000 00000000
    • 10101100 00010000 00000001 00000000

    Above you can see that the first 23 bits are the same, that's why we use the /23 summary.


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