[79471] in North American Network Operators' Group
Re: AS prepending
daemon@ATHENA.MIT.EDU (Patrick W Gilmore)
Fri Apr 8 10:36:51 2005
In-Reply-To: <20050408142809.38817.qmail@web51903.mail.yahoo.com>
Cc: Patrick W Gilmore <patrick@ianai.net>
From: Patrick W Gilmore <patrick@ianai.net>
Date: Fri, 8 Apr 2005 10:34:05 -0400
To: nanog@merit.edu
Errors-To: owner-nanog@merit.edu
On Apr 8, 2005, at 10:28 AM, Philip Lavine wrote:
> I am using AS prepending to favor one ISP over
> another, in a BGP multihomed/multiISP scenario. Why
> does the ISP receiving the prepends fail to add my
> network into their routing table? Is this a "feature"
> of BGP, or have I gone too far with 3 prepend
> statements.
If they are both transit providers, then they are broken.
If they are peers, the second ISP is probably preferring the route it
hears through your transit provider because there are fewer AS hops.
--
TTFN,
patrick
