EIGRP route summarization

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What would you find in an EIGRP routing table if route summarization is
configured on the routers Serial0 interface, and it summarizes routes
learned from its Ethernet0 interface?

A. A summary route pointing to the Serial0 interface.

B. A summary route pointing to the Ethernet0 interface.




Re: EIGRP route summarization


B i think

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Re: EIGRP route summarization



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So you are not sure. Cause I thought A should be the answer




Re: EIGRP route summarization


Here is another answer choice. Sorry for inconvenience

C. A summary route pointing to the Null0 interface.


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Re: EIGRP route summarization


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A is the answer.  It summarizes on the interface that it is advertising, not
learning.  It will learn the routes on E0 and summarize those routes out S0,
with the route being back to interface S0.




Re: EIGRP route summarization


hey scooby,
i was also thinking that serial should be the correct answer but wasnt sure.
thanks.

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not
S0,




Re: EIGRP route summarization


sorry about that

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Re: EIGRP route summarization


no worries

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is
advertising,
out




Re: EIGRP route summarization


Correct Answer is C (A summary route pointing to the Null0 interface)
Thanks to Owen Roth

"In EIGRP, the router doing the summarization will build a route to null0
(line 18) for the summarized address. Let's check Shannon's routing table:

Shannon#sh ip route 172.20.0.0
....
     172.20.0.0/16 is subnetted, 6 subnets
C       172.20.100.0/24 is directly connected, Ethernet0
C       172.20.101.0/24 is directly connected, Ethernet1
D       172.20.0.0/16 is a summary, 00:12:11, Null0
C       172.20.102.0/24 is directly connected, Ethernet2"

http://www.oreilly.com/catalog/iprouting/chapter/ch04.html

Cheers,
Owen

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summarization
routes




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