From: Mas Kato (tealp729@xxxxxxxx)
Date: Mon Apr 23 2001 - 15:08:29 GMT-3
This might provide an interesting option--although the route will not
appear in the routing table, it *should* appear in all of the link-state
DBs throughout the area, right? Hmmm... I wonder in what sort of
contrived scenario might we need to deploy that feature into?... ;-)
Mas Kato
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com]On Behalf Of
Mannan Venkatesan
Sent: Monday, April 23, 2001 7:41 AM
To: Michel GASPARD
Cc: ccielab@groupstudy.com
Subject: Re: Re: summary-address in ospf and redistribution
Hi,
I was playing with scenario(OSPF -> IGRP redistribution with
summary-address) last night and found the following.
When I used summary-address command with 'not-advertise' option, the E2
summary route (170.100.2.0) appeared only in the OSPF database but not
in
the routing table (R3). I didn't use any filter on the redistribution
router.
Mannan
----- Original Message -----
From: "Michel GASPARD" <mgaspard@cisco.com>
To: "Mannan Venkatesan" <venkat_m@ins.com>
Cc: "Connary, Julie Ann" <jconnary@cisco.com>; <ccielab@groupstudy.com>;
"Mannan Venkatesan" <mv70@lucent.com>
Sent: Friday, April 20, 2001 2:29 AM
Subject: OSPF: Re: summary-address in ospf and redistribution
> Mannan,
>
> 1) According to Doyle (p723-724), OSPF "summary-address" can only be
> used for summarization of external routes, in the ASBR, INTO the OSPF
> process.
>
> 2) From:
>
>
http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/12cgcr/n
p1_r
/1rprt1/1rospf.htm#xtocid677242
>
> we have:
>
> "
> Using this command for OSPF causes an OSPF autonomous system boundary
> router (ASBR) to advertise one external route as an aggregate for all
> redistributed routes that are covered by the address. For OSPF, this
> command summarizes only routes from other routing protocols that are
> being redistributed into OSPF.
> "
>
>
> 3) Well, that is the official version. Some people claims it is also
> working the other way around (OSPF => other). I will test that this
> afternoon.
>
> 4) A quick check on groupstudy's archive with "summary-address" give
you
> PLENTY of more stuff to read!!
>
> Regards,
>
> Michel
>
> Mannan Venkatesan wrote:
> >
> > Julie,
> > Thanks for the response. I tried it and found the following. I would
like to
> > confirm whatever I understand is right. Let me re-draw my scenario.
> > I have used class B address, 170.100.0.0
> >
> > I I/O O
> > ------- r1----------r2-----------r3-------------
> > 1.0/24 4.0/24 2.4/30 /29,/28,27 subnets
> >
> > I configured everything without redistribution, worked fine. Then, I
> > configured redistribution from IGRP to OSPF on R2, worked as
expected.
Then
> > I typed 'summary address 170.100.2.0 255.255.255.0' under ospf
process
(for
> > OSPF -> IGRP redistribution) which created a summary address
170.100.2.0 -
> > >null 0 on R2 routing table. On R3 routing table it appeared as E2
route.
> > But note that I haven't configured OSPF -> IGRP redistribution yet.
> > So, the E2 route was inserted by OSPF process. It is not coming back
from
> > IGRP because there was no OSPF -> IGRP redistribution. I had a
impression
> > that the E2 route is because of route loop.
> > So, I can't filter that summary router on r2. If I do, OSPF -> IGRP
red.
> > wouldn't work which is happening when I used distribution-list out.
> >
> > Is it a normal behavior of OSPF? Or am I missing some OSPF basic?
> >
> > Thanks,
> > Mannan
> >
> > ----- Original Message -----
> > From: "Connary, Julie Ann" <jconnary@cisco.com>
> > To: "Mannan Venkatesan" <venkat_m@ins.com>
> > Sent: Thursday, April 19, 2001 9:40 AM
> > Subject: Re: summary-address in ospf and redistribution
> >
> > > Mannan,
> > >
> > > it is pratically impossible to tell from your diagram what your
topology
> > > is. I am assuming that igrp is running between routers r1 and r2.
R2
is
> > the
> > > re-distribution router and area 0 is between r2 and r3, area 1 is
between
> > > r3 and r4. The OSPF area is variably subnetted of the Ip address
> > > 170.100.2.0 and 170.100.4.0? And the IGRP area is 170.100.1.0/24?
So
you
> > > are trying to summarize the 170.100.2.0 network to a class 24
boundary
to
> > > redistribute into EIGRP? And why are you not redistributing OSPF
into
> > > IGRP? I think this is part of your problem. Try that and let me
know.
> > >
> > > Unfortunately the example at the bottom, upon closer inspection is
> > > backwards. I thinkthe two access-lists should be swapped. I edited
this
> > > below.
> > >
> > > Julie Ann
> > >
> > >
> > > At 10:14 PM 4/18/2001 -0400, you wrote:
> > > >Hi,
> > > >I was trying this scenario. Have a question for you. Where did
you
use
> > > >route-map? When I used route-map on the redistribution router,
the
> > summary
> > > >route( 170.100.2.0 ->null0) disappeared from the routing table
and I
> > > >couldn't ping OSPF networks from IGRP router.
> > > >
> > > > IGRP
IGRP/OSPF
> > > >Area 0 OSPF Area 1
> > >
>
-------------------R1------------------------R2-----------------------
---- > > R > > > >3----------------------R4-- > > > > 170.100.1.0/24 170.100.4.0/25 170.100.2.4/30 > > > >/29, /28, /30 networks > > > > > > > > > > > >R2 Config: > > > >router ospf 10 > > > > summary-address 170.100.2.0 255.255.255.0 > > > > redistribute igrp 10 metric-type 1 subnets route-map sum > > > > network 170.100.2.4 0.0.0.3 area 0 > > > >! > > > >router igrp 10 > > > > network 170.100.0.0 > > > >! > > > >no ip classless > > > >access-list 1 permit 170.100.2.0 0.0.0.255 > > > >route-map sum deny 10 > > > > match ip address 1 > > > >! > > > >route-map sum permit 20 > > > >! > > > > > > > >I could able to filter that E1 route on R3 by using distribution-list in. > > > >But the OSPF database still had that E1 route which is the normal > > behavior > > > >of OSPF. > > > > > > > >I would like to filter it on the redistribution router. Any advice? > > > > > > > >Thanks, > > > >Mannan > > > > > > > > > > > > > > > > > > > > > > > >----- Original Message ----- > > > >From: "Connary, Julie Ann" <jconnary@cisco.com> > > > >To: <SherefMohamed@cdh.org> > > > >Cc: <ccielab@groupstudy.com>; <nobody@groupstudy.com> > > > >Sent: Tuesday, January 23, 2001 12:31 PM > > > >Subject: Re: summary-address in ospf and redistribution > > > > > > > > > > > >I tested a similar theory with route-maps and worked > > > >like a champ. > > > >Beware - the fatkid lab posted solution > > > >(http://www.fatkid.com/html/501_expert_redistribution_-_ro.html) > > > > does not use route-maps - and the posted routing tables - however > > reflect > > > >that route-map were used. > > > > > > > >Julie Ann > > > > > > > >At 09:55 AM 1/23/2001 -0600, SherefMohamed@cdh.org wrote: > > > > > > > > >You need to do mutual redistribution between OSPF and IGRP, > > > > >the idea is to not allow IGRP send back to OSPF the summary address ! > > > > >Here is how I will do it: > > > > > > > > > >! > > > > >router igrp 2 > > > > >.......... > > > > >distribute-list 11 out ospf --- key here is to distribute the > > > > 172.10.2.0 subnet into igrp. Of course this example will only > > > > > > distribute the 172.10.2.0 subnet and > > no > > > others. > > > > > > > >.......... > > > > >! > > > > >router ospf 1 > > > > >........... > > > > >distribute-list 10 out igrp --- key here is not to redistibute it back > > > > into OSPF. > > > > >........... > > > > >! > > > > > > > > > >access-list 10 deny 170.10.2.0 0.0.0.255 > > > > >access-list 10 permit 0.0.0.0 255.255.255.255 > > > > >! > > > > >access-list 11 permit 172.10.2.0 0.0.0.255 > > > > >access-list 11 deny 0.0.0.0 255.255.255.255 > > > > > > > > > >Please test it & tell me how it works ! > > > > > > > > > >Thanks > > > > >Sheref > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > "Connary, > > > > > > > > > > Julie > > > > > Ann" To: ccielab@groupstudy.com > > > > > > > > > > <jconnary@cis cc: > > > > > > > > > > co.com> Subject: summary-address > > in > > > > > ospf and redistribution > > > > > Sent > > > > > by: > > > > > > > > > > nobody@groups > > > > > > > > > > tudy.com > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > 01/23/2001 > > > > > > > > > > 08:37 > > > > > AM > > > > > > > > > > Please > > > > > > > > > > respond > > > > > to > > > > > > > > > > "Connary, > > > > > > > > > > Julie > > > > > Ann" > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >Hi All, > > > > > > > > > >I ran across a practice lab and another fat-kid lab that use the ospf > > > > >summary-address to overcome > > > > >vlsm to fsm issues when redistributing ospf into igrp: > > > > > > > > > > > > > > > > > > > >situation: The ospf connected interface has a longer mask than the IGRP > > > > >connected interface. > > > > > area-range does not work because it is on the > > same > > > > >router. > > > > > > > > > > The Fatkid lab - expert redistribution - solves this with > > a > > > > >summary-address. > > > > > > > > > >Question - does this not inject E2 routes back into your OSPF domain? > > > > > > > > > > > > > > >OSPF area 2 > > > > >170.10.128.4 - 255.255.255.192 > > > > >| > > > > >| > > > > >| > > > > >R4 -----------IGRP - 170.10.2.4 255.255.255.0 > > > > > > > > > >To redistribute the ospf interface into IGRP a summary-address is > > > > >used: summary-address 170.10.128.0 255.255.255.0 > > > > > > > > > >But then in the ospf domain you get an E2 route to 170.10.128.0 in > > your > > > > >ospf domain. > > > > > > > > > >So how do you prevent this E2 route into OSPF - can you filter it? > > > > > > > > > >Thoughts? > > > > > > > > > >remember - no static, no default. > > > > > > > > > >Julie Ann > > > > > > > > > > > > > > > > > > > > > > > > > > >----------------------------------------------------------------------- - > > > > > Julie Ann Connary > > > > > | | Network Consulting Engineer > > > > > ||| ||| Federal Support Program > > > > > .|||||. .|||||. 13635 Dulles Technology > > Drive, > > > > >Herndon VA 20171 > > > > > .:|||||||||:.:|||||||||:. Pager: > > > >1-888-642-0551 > > > > > c i s c o S y s t e m s Email: jconnary@cisco.com > > > > > > > > > > > >----------------------------------------------------------------------- - > > > >----------------------------------------------------------------------- - > > > > Julie Ann Connary > > > > | | Network Consulting Engineer > > > > ||| ||| Federal Support Program > > > > .|||||. .|||||. 13635 Dulles Technology > > Drive, > > > >Herndon VA 20171 > > > > .:|||||||||:.:|||||||||:. Pager: 1-888-642-0551 > > > > c i s c o S y s t e m s Email: jconnary@cisco.com > > > > > > > >----------------------------------------------------------------------- - > > > ---------------------------------------------------------------------- -- > > > Julie Ann Connary > > > | | Network Consulting Engineer > > > ||| ||| Federal Support Program > > > .|||||. .|||||. 13635 Dulles Technology Drive, > > > Herndon VA 20171 > > > .:|||||||||:.:|||||||||:. Pager: 1-888-642-0551 > > > c i s c o S y s t e m s Email: jconnary@cisco.com > > > > > > ---------------------------------------------------------------------- -- > > **Please read:http://www.groupstudy.com/list/posting.html **Please read:http://www.groupstudy.com/list/posting.html **Please read:http://www.groupstudy.com/list/posting.html
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