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Forum Replies

  1. awesome lessons. especially the

    "EIGRP auto-summary will only create summary routes for directly connected networks, not for routes you learn from other EIGRP routers."

    i just learned it here.

    thanks rene!

  2. Good to hear you like it! I think that's one of the things that is important to know, most people assume EIGRP will just summarize anything when you use auto-summary.

  3. Are you testing our troubleshooting skills as we move through the lessons? You started us off configuring routes in AS 12 for EIGRP and then moved onto AS 1. My head was spinning for a few minutes when I couldn't replicate the console output that you were getting. When I made sure everything was in AS 12 it all came together! :slight_smile:

    Appreciate all of your hard work, doing these labs is really putting it all together for me. Keep it up, dude!

  4. Rene
    this a great article and explaination


  5. Hi Rene

    Thank you that was a useful lesson.
    There is an important thing that you didn't explicitly mention and is important.

    • The eigrp router will only announce an auto-summary out an interface if the classful network of the interface is different from the classful network of the interface it learnt the network from. In other words if it has 2 interfaces and both are in the same network class, it will never send an auto summary out (this is how I understood the cisco info, haven't labbed it).
      Cisco says it this way "When a router has multiple working interfaces, and those interfaces use IP addresses in different classful networks, the router advertises a summary route for each classful network on interfaces attached to a different classful network.

    What I took away from the lesson is:
    -A router will only send out auto-summaries of connected networks (never learnt)
    -A router will only auto-summarize between network classes.


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