From: Brian Hescock (bhescock@xxxxxxxxx)
Date: Sat Jan 20 2001 - 16:25:52 GMT-3
They're referring to filtering routes between routing protocols, not
within ospf. What you're referring to applies when using a
distribute-list within ospf to try to control routes within ospf. You can
use a distribute-list out at your ASBR to filter external routes
into ospf. But you're correct you can't do it anywhere else, you would
need to use a distribute-list in. The reason for this is compliance with
the RFC, although Cisco gives you the option of filtering the routes from
the routing table. However, distribute-list in (with regard to
ospf) filters the routes in the routing table for ONLY that one
router. It doesn't filter the lsa's and you would need to do a
distribute-list in on each router if you wanted to
keep the route out of the routing table.
B.
On Sat, 20 Jan 2001, Ronnie Royston wrote:
> I may have to take this back, but I remember from practicing with OSPF, that
> you cannot filter outbound routing updates with a distribute-list, only
> inbound. I can't get to my rack right now (circuit is down) so I am
> speaking only from memory. For other routing protocols, this is not the
> case. Anyone else notice this?
>
> -----Original Message-----
> From: Atif Awan [mailto:atifawan@hotmail.com]
> Sent: Saturday, January 20, 2001 9:33 AM
> To: chuck@cl.cncdsl.com; ccielab@groupstudy.com
> Subject: Re: Distribute-List vs Route-Map issues
>
>
> The distribute list 1 out eigrp 100 command will filter routes that are
> getting redistributed from eigrp 200 into ospf process and not from ospf
> into eigrp. You are placing the distribute list under the wrong routing
> protocol. Do this :
>
> router eigrp 100
> distribute-list 1 out ospf 300
>
> where distribute-list 1 is the access-list you created.
>
> Regards
> Atif
>
>
> >From: "Chuck Larrieu" <chuck@cl.cncdsl.com>
> >Reply-To: "Chuck Larrieu" <chuck@cl.cncdsl.com>
> >To: "CCIE_Lab Groupstudy List" <ccielab@groupstudy.com>
> >Subject: Distribute-List vs Route-Map issues
> >Date: Sat, 20 Jan 2001 07:55:19 -0800
> >
> >Two routing domains. Single redistribution point. Requirement for
> >summarization out of each domain into the other.
> >
> >EIGRP-----ASBR-----OSPF
> >182.18.0.0 172.16.0.0
> >
> >ASBR configs ( partial )
> >
> >Router eigrp 200
> >Netw 182.18.0.0
> >Redist ospf 300 metric etc
> >
> >Router opsf 300
> >Netw ( several statements )
> >Redist eigrp 200 metric etc subnets
> >
> >Without any additional configuration, everything behaves as I expect. All
> >routes are appearing in each domain
> >
> >To summarize the eigrp routes, I add the statement summary-address
> >182.18.0.0 255.255.0.0
> >
> >Again, behaviour is as I expect. The summary appears throughout the OSPF
> >domain as it should. And it is leaked back into the eigrp domain, which I
> >expect because there is no filtering.
> >
> >Now here is where it gets frustrating.
> >
> >Access-list 1 permit 172.16.0.0 0.0.255.255
> >
> >Distribute-list 1 out eigrp 200 ( under the ospf process )
> >
> >This does not work. the 182.18.0.0 summary address appears throughout the
> >eigrp domain, after clear ip route * everyplace I can think of. It does not
> >appear to be artifact from earlier configurations. Oh- also the summary
> >route disappears f the ospf domain as well.
> >
> >If I take that same access list and use it in a route map
> >
> >Route-map ospf-eig permit 10
> >Match ip address 1
> >
> >And then make the appropriate modifications under the ospf process, the
> >summary disappears. ( there were a couple of variations of access-lists and
> >distribute-lists I tried, btw, both in eigrp and ospf. Similar results )
> >
> >Anyone know what gives?
> >
> >I see from book examples that folks tend not to use distribute-list
> >options. I could not find any caveats in the documentation, but you know
> >how
> >that goes. ;->
> >
> >
> >Chuck
> >http://www.1112.net/lastpage.html
> >
> >
> >
> >
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