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Forum Replies

  1. Awesome way of explaining!! Thanks…I never EVER Leave a comment anywhere,but could not help here :slight_smile:

  2. Hi Rene,

    On below config advertisement

    John(config)#router eigrp 1
    John(config-router)#no auto-summary 

    if i add below config on it

    John(config)#router eigrp 1
    John(config-router)#passive-interface loopback 0

    That means traffic for network and won’t pass on interface loop back 0 ?

  3. Hi Taslim,

    There are a couple of parameters that have to match:

    • Authentication
    • AS Number
    • K values
    • Subnet
    You can also take a look at this post where I walk you through the most common issues with the EIGRP neigbor adjacency:

    EIGRP Neighbor Adjacency Troubleshooting


  4. Hello Qifeng

    In EIGRP, if you don’t use the no auto-summary command, the router will assume a classful network address regardless of the wildcard mask you enter.

    Once you enter the no auto-summary command, EIGRP will begin sending the wildcard mask information as well.

    As for RIP, version 1 will send classful routing information. In order to send classless routing information, RIP must be configured to use Version 2 AND must include the no auto-summary command.

    Now the difference between EIGRP and RIP is that when you configure the network command for RIP, you don’t input a wildcard mask. It won’t let you. Take a look at this output:

    Router#configure terminal
    Enter configuration commands, one per line.  End with CNTL/Z.
    Router(config)#router rip
    Router(config-router)#version 2
    Router(config-router)#network ?

    The only option it gives you after the network address is <cr>.

    So in RIP, if you configure version 2 and no auto-summary, the router will use the subnet mask configured on the interface associated with the network. So for the example you used, if you have two interfaces with IP addresses and respectively and you configure those networks using RIP, it will use the subnet masks (/24) configured on the interfaces themselves.

    I hope this has been helpful!


  5. That’s really helpful, thanks Laz!

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