RE: OSPF Virtual Links

My only other thought after thinking about it a bit is if you had another
router connected to Area5. One did a summary and the other the more
specific routes. You could then filter the more specific routes on R3 with
a distribute list and let the summary go thru. Still a need for a
difference in the topology.

Regards,

Tyson Scott - CCIE #13513 R&S, Security, and SP

Managing Partner / Sr. Instructor - IPexpert, Inc.

Mailto: <mailto:tscott_at_ipexpert.com> tscott_at_ipexpert.com

From: Grammer, Christopher [mailto:cgrammer_at_essilorusa.com]
Sent: Tuesday, June 22, 2010 7:55 PM
To: Tyson Scott
Cc: Bob Sinclair; Cisco certification
Subject: Re: OSPF Virtual Links

So to finish this question:

If the scenario is changed a bit to look like this:

(area5) R1 --(Area0)-- R2 --(Area0) -- R3 -- (Area 3)

There is no way to summarize routes at R3 that originated from area 5?

--Except for the multiple process redistribution--

This sounds wrong...but I haven't been able to find a way.

On Tue, Jun 22, 2010 at 6:47 PM, Grammer, Christopher
<cgrammer_at_essilorusa.com> wrote:

I like it :)

On Tue, Jun 22, 2010 at 6:40 PM, Tyson Scott <tscott_at_ipexpert.com> wrote:

Without additional information on the lab I would also state that maybe the
question was not looking for virtual-links.

If the routes originate in area 5 that is where the summary needs to be
created towards area 0. If one OSPF process is used. But maybe the solution
is to create two processes. Redistribute between the processes on R3 and use
the summary command for external routes on R3 for redistribution into Area
3. At that point as it is a single area 3 in the second process you don't
need an area 0. And you have met the requirement of summarizing on R3.

Just a thought.

Regards,
 
Tyson Scott - CCIE #13513 R&S, Security, and SP
Managing Partner / Sr. Instructor - IPexpert, Inc.
Mailto: tscott_at_ipexpert.com

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of Bob
Sinclair
Sent: Tuesday, June 22, 2010 7:05 PM
To: cgrammer_at_essilorusa.com; 'Cisco certification'
Subject: RE: OSPF Virtual Links

Quick thought: If they are area 5 routes, then shouldn't the summary
command be "area 5 range..." I believe the command references the source
area.

HTH,

-Bob Sinclair

> -----Original Message-----
> From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
> cgrammer_at_essilorusa.com
> Sent: Tuesday, June 22, 2010 6:52 PM
> To: ccielab_at_groupstudy.com
> Subject: OSPF Virtual Links
>
> I am having a difficult time finding information regarding a detailed
> explanation of OSPF virtual links with regards to route summarization
> on the
> remote end of the virtual link router.
>
> I am working on a practice lab that:
>
> (area5) R1 --(area0)--- R2 ----(area1) ---R3 ---(area3) --- R4
>
> The requirement is to connect R2 to R3 with a virtual link to allow
> area5
> routes to be propagated to R4.
> 1.1.0.0/24
> 1.1.1.0/24
> 1.1.2.0/24
> 1.1.3.0/24
>
> The routes show up on R4 as expected, but the next requirement is to
> summarize
> the routes at R3 so that it shows up as 1.1.0.0/22 on R4.
>
> Since R3 is now a member of Area0, I would think i can use
> area 0 range 1.1.0.0 255.255.252.0
>
> But,this doesn't work.
> It seems that there are some peculiar characteristics regarding virtual
> links
> and area 0, but there isn't much documentation outside of the
> rudimentary
> explanation and troubleshooting commands.
>
> Thanks in advance for everyones help,
>
>
> Chris
>
>
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Received on Wed Jun 23 2010 - 10:03:04 ART