[56703] in North American Network Operators' Group
Re: Route Supression Problem
daemon@ATHENA.MIT.EDU (Jack Bates)
Wed Mar 12 16:26:09 2003
From: "Jack Bates" <jbates@brightok.net>
To: "Iljitsch van Beijnum" <iljitsch@muada.com>,
"Danny McPherson" <danny@tcb.net>
Cc: <nanog@merit.edu>
Date: Wed, 12 Mar 2003 15:28:50 -0600
Errors-To: owner-nanog-outgoing@merit.edu
From: "Iljitsch van Beijnum"
> > Nope. It's per-prefix.
>
> If that is the case then dampening is severely broken, because then a
> router that receives a prefix over two paths will lose *both* if _one_
> flaps.
>
Which makes me wonder what happens when one of my BGP peers is flapping and
the other is holding stable with an AS prepend on it.
> In any case, it is done on the eBGP router receiving the prefix/route,
> so unless the two ISPs in question peer using the same router as they
> use to connect to Jack's AS, there still shouldn't be any flapping
> multiplication. (Hm, unless that happened inside Jack's network...?)
>
My network is too simplistic to have flapping multiplication. The only
difference between the customers routes and my own are that I do an AS
prepend on all my networks going out to one of my peers so that the peer
only sends customer traffic to me and serves as a last resort, while my
customers routes out all peers without modification.
-Jack
