From: Bauer, Rick (BAUERR@xxxxxxxxxxx)
Date: Mon Apr 29 2002 - 15:25:31 GMT-3
Except for the fact that synchronization is enabled, the routes are not in
IGP, and you can't use statics. Full mesh IBGP won't help because you need
EBGP to relieve the sync issue. You can suffer from the same sync issues on
a p2p link where there are no sub-optimal routing issues. I am not
recommending to use this in the real world. What I am suggesting is that
people understand how bgp works and how to make it work with certain
restrictions.
-----Original Message-----
From: Peter van Oene [mailto:pvo@usermail.com]
Sent: Monday, April 29, 2002 2:14 PM
To: Bauer, Rick; 'ccielab@groupstudy.com'
Subject: RE: BGP OSPF sync with Route Reflecter
Well, first off, a routed network where each router is a confederate sub-as
would deliver lots of sub-optimal routing. Further, reconfiguring one's
network into such a kludge simply to make an antiquated feature work is
really not something I'd advise.
I would much rather full mesh my IBGP than confederate in this ugly case.
Pete
At 02:09 PM 4/29/2002 -0400, Bauer, Rick wrote:
>Why is that?
>
>-----Original Message-----
>From: Peter van Oene [mailto:pvo@usermail.com]
>Sent: Monday, April 29, 2002 1:29 PM
>To: ccielab@groupstudy.com
>Subject: RE: BGP OSPF sync with Route Reflecter
>
>
>if this is the solution, I would suggest that the question is seriously
>flawed.
>
>At 08:58 AM 4/29/2002 -0400, Bauer, Rick wrote:
> >Actually, a confederation is the way to work around the sync issue, if
you
> >can not disable sync, or put the routes in the igp, or add statics to the
> >ibgp peer receiving the routes. HTH....
> >
> >-----Original Message-----
> >From: Joe Higgins [mailto:netsat@optonline.net]
> >Sent: Sunday, April 28, 2002 9:03 AM
> >To: Michael Jia
> >Cc: ccielab@groupstudy.com
> >Subject: Re: BGP OSPF sync with Route Reflecter
> >
> >
> >This scenario of bgp and ospf over a route reflector setup in absolute
>terms
> >cannot work because of the inherent design of ospf and bgp. Previous
posts
> >explain why this is so. I suggest that if one finds oneself in a
situation
> >where they find it impossible to put in the "no synchronization" command
> >then
> >they should start thinking outside the "BOX" and possible peer the
route
> >reflector clients with each other, or run igrp or eigrp on top of ospf on
> >the
> >route reflector portion of their network. This horse has been beaten up
> >pretty
> >badly. Good luck.
> >Joe H.
> >
> >Michael Jia wrote:
> >
> > > Hi,
> > >
> > > I have a general question regarding BGP and OSPF sync when router
> >reflector
> > > is
> > > used. I've seen some threads discuss it before on the list.
> > >
> > > The scenerio is like :
> > >
> > > R1 ---- R2------ R3
> > >
> > > All R1, R2, R3 are in same AS, R1 and R3 peer to external AS.
> > > R2 is the route reflecter with iBGP peered to both R1 and R3.
> > > R1 and R3 doesn't peer with each other.
> > > OSPF is used as IGP for R1, R2 and R3.
> > >
> > > When a eBGP route is redistritued at R1 into OSPF. The route's
> > > BGP id is R1, its OSPF id is also R1.
> > > iBGP syncs at R2 without question.
> > >
> > > However, it doesn't sync at R3. Because from R3, it sees iBGP id as
R2,
> > > the Reflector's ID, but OSPF id is still R1. (Am I right? please
correct
> >me
> > > if my logic is wrong. At a live lab, if R3 peer with R1 , the route
will
> > > sync
> > > immediatly. In R3's routing table, it clearly has the route and the
next
> >hop
> > > route as OSPF routes. )
> > >
> > > The question is, how to make it sync without using "no sync" at R3?
> > >
> > > Thanks a lot.
> > >
> > > Michael
This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 10:58:22 GMT-3