Summarize EIGRP

NetstudentNetstudent Member Posts: 1,693 ■■■□□□□□□□
If I summarize a bunch of routes with EIGRP and I put that summary route on the interface, is that the only route that EIGRP will advertise?

I ask because I want to summarize some routes that are coming into my network via EIGRP. But the place that these routes are coming from is not contiguous. I have routes coming in from this site that are in different "classes".


I have a bunch of routes coming in that are like 192.168.177.0 .4 .8 .12

but routes are also coming in from 10.156.0.0

Can I summarize both of these major classes on the same interface or am I limited to 1 summary route?

ALso is that summary route the only thing that EIGRP will advertise out the interface?

I think I know the answer but I want to be sure. I'm thinking that I am limited to only 1 summary route, but EIGRP will advertise other routes that are not included in the supernet address. I should test in dynamips.
There is no place like 127.0.0.1 BUT 209.62.5.3 is my 127.0.0.1 away from 127.0.0.1!

Comments

  • mikearamamikearama Member Posts: 749
    You can summarize both networks:

    ip summary-address eigrp 1 192.168.177.0
    ip summary-address eigrp 1 10.156.0.0

    Because they don't overlap, you'll be able to apply both summary addresses to the same interface.

    And nothing that's covered by the summaries will get sent out the interface... just the summaries.
    There are only 10 kinds of people... those who understand binary, and those that don't.

    CCIE Studies: Written passed: Jan 21/12 Lab Prep: Hours reading: 385. Hours labbing: 110

    Taking a time-out to add the CCVP. Capitalizing on a current IPT pilot project.
  • NetstudentNetstudent Member Posts: 1,693 ■■■□□□□□□□
    oh damn...I guess I didn;t know ....Thanks Mike


    icon_lol.gif
    There is no place like 127.0.0.1 BUT 209.62.5.3 is my 127.0.0.1 away from 127.0.0.1!
  • gojericho0gojericho0 Member Posts: 1,059 ■■■□□□□□□□
    What about if we had another network to summarize?

    10.157.0.0 /16

    Is it legal to summarize two similar major nets even though due to the prefix they are different networks?
  • mikearamamikearama Member Posts: 749
    You mean, something like:

    ip summary-address eigrp 1 10.156.0.0 0.0.255.255
    ip summary-address eigrp 1 10.157.0.0 0.0.255.255

    ??

    That should work... they're clearly different networks. Though I suppose the correct way to summarize that would be to include 157 in the 156 mask.

    I'll throw that in the lab over the weekend and try it.
    There are only 10 kinds of people... those who understand binary, and those that don't.

    CCIE Studies: Written passed: Jan 21/12 Lab Prep: Hours reading: 385. Hours labbing: 110

    Taking a time-out to add the CCVP. Capitalizing on a current IPT pilot project.
  • NetstudentNetstudent Member Posts: 1,693 ■■■□□□□□□□
    I just tested it in the dynamips lab and you are right. You can have multiple summary address statements on the interface, and it advertises everything else not included in the summary as is. So I was only half wrong. icon_cool.gif
    There is no place like 127.0.0.1 BUT 209.62.5.3 is my 127.0.0.1 away from 127.0.0.1!
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