RE: EIGRP /IGRP

From: yakout esmat (yesmat@xxxxxxxxxxxxxx)
Date: Thu Jul 18 2002 - 11:30:59 GMT-3

   
Sorry, you are right -:)

1)auto-summary will summarize networks when crossing major net boundry

2) "ip summary-address eigrp" interface command allows EIGRP to summarize
both internal and/or external routes to any bit boundry

Back to your question, even though you have auto-summary on, routes crossing
major net boundry will not be summarised if they are external.

Check out this document http://www.cisco.com/warp/public/103/eigrp5.html it
is excellent.

Yakout

-----Original Message-----
From: ccie candidate [mailto:ccie1@lycos.com]
Sent: Friday, July 19, 2002 12:05 AM
To: ccie candidate; ccielab@groupstudy.com; yakout esmat
Subject: RE: EIGRP /IGRP

Yakut ;
your first statement is right , redist between EIGRP and IGRP with the same
AS number should follow the same rules of redistribution ,the difference is
that it is done automatically .

your first rule is also right ,IGRP was not supposed to see the variable
subnets in the EIGRP domain ( and my question was why EIGRP summarized them
so that IGRP see them as for example /24 mask while they were /28 on the
EIGRP domain )

your 2) rule is wrong , auto summary is not meant for that , auto summary
will not allow the EIGRP router to send variably subnets from any major
class network

i didnt understand your last rule , however ip summary address command is to
summarize EIGRP domain to external protocols and not the other way
around -:)

now back to my question , WHY the routes appeard on the IGRP domain
summarized while i disable all summarization on EIGRP ?? 

--

On Thu, 18 Jul 2002 23:37:20
 yakout esmat wrote:
>Redistribution between EIGRP/IGRP using the same AS number follow the same
>rules as any normal redistribution between VLSM/FLSM.
>
>1) If both protocols using the same major nework but different masks, then
>IGRP will not see the networks with different subnets than its own.
>
>2) when you diable auto-summary in EIGRP, that only applies to routes
>redistributed from IGRP (or any other protocol) into EIGRP and not the
other
>way around.
>
>3) You can use the interface summary-address command if you wanted to send
>summary to next neighbor
>
>HTH
>
>Yakout
>
>-----Original Message-----
>From: nobody@groupstudy.com [mailto:nobody@groupstudy.com]On Behalf Of
>ccie candidate
>Sent: Thursday, July 18, 2002 10:30 PM
>To: ccielab@groupstudy.com
>Subject: EIGRP /IGRP
>
>
>guys ;
>i have a scenario where EIGRP and IGRP are having the same AS number and
>reditributing autmatically , the EIGRP domain have  different subnets
>(masks) .
>i disabled the auto-summary on all routers in eigrp domain including the
>redist point ,however the routers in IGRP domain can see all the routes in
>EIGRP domain as if EIGRP summarized them  .
>
>am i supposed to do this manually on EIGRP by using the summary address
>command ??? as per doyle vol 1 ?
>
>what am i missing here ?
>
>
>candidate
>
>

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