nanog mailing list archives
Re: BGP Configuration Problem
From: Jon Green <jcgreen () netins net>
Date: Thu, 07 Nov 1996 21:34:45 -0600
On Thu, 07 Nov 1996 22:21:15 -0500, lambert () psc edu writes:
We are having a BGP configuration problem which looks trivial but is not working the way we expect. I'm going to throw myself on the mercy of the court and ask for help. There are three routers A, B and C. These are in ASa, ASb and ASc, respectively. B imports 10.1.64/19 from A and 10.1/16 from C. What we were expecting was for B's route to the /19 to be via A, just because this is the more specific route. However, the only route (both in the BGP and routing tables on B) is for the entire /16 via C. I have a hunch that what is happening is that B is saying "gee, I can get to the entire /16 by going through C, so why bother with A". If I'm not mistaken, this can be fixed by introducing local_pref for both peers. Could someone please comment on this?
If B is hearing the route from A, it should at least show up in the BGP table. The behavior that you expect is what it should be doing; it sounds to me like B is not even hearing the BGP announcement from A. Check how you have accept policies configured on B, and how you have announce policies configured on A, and when in doubt, call your router vendor for help. :) -Jon ----------------------------------------------------------------- * Jon Green * * * jcgreen () netINS net * This space for rent pending * * Finger for Geek Code/PGP * me thinking up a witty quote. * * #include "std_disclaimer.h" * * ------------------------------------------------------------------------- - - - - - - - - - - - - - - - - -
Current thread:
- BGP Configuration Problem Michael H. Lambert (Nov 07)
- Re: BGP Configuration Problem Jon Green (Nov 07)
- Re: BGP Configuration Problem Jian Li (Nov 08)
- Re: BGP Configuration Problem Avi Freedman (Nov 08)
- Re: BGP Configuration Problem Jon 'tex' Boone (Nov 08)
- <Possible follow-ups>
- Re: BGP Configuration Problem Rob Liebschutz (Nov 08)
- Re: BGP Configuration Problem Jon Green (Nov 07)