[72601] in North American Network Operators' Group
Re: BGP Dampening question
daemon@ATHENA.MIT.EDU (Iljitsch van Beijnum)
Mon Jul 19 17:07:18 2004
In-Reply-To: <20040716034654.22882.qmail@web61303.mail.yahoo.com>
Cc: nanog@merit.edu
From: Iljitsch van Beijnum <iljitsch@muada.com>
Date: Mon, 19 Jul 2004 23:06:32 +0200
To: D Train <dtrain_04@yahoo.com>
Errors-To: owner-nanog-outgoing@merit.edu
On 16-jul-04, at 5:46, D Train wrote:
> If I keep seeing the physical connection to City A flapping, of course
> bgp will flap, but will I be able to use route dampening to control
> the instability
No. BGP flap dampening only works on routes that go up and down
periodically while the BGP session they're learned over stays up. When
the session goes down the dampening info is removed.
But it doesn't matter: you're screwed both ways. If you keep routing
stable you lose packets, if you import the flapping into your routing
protocols those become unstable. You need stable links.