[116842] in North American Network Operators' Group
RE: Redundancy & Summarization
daemon@ATHENA.MIT.EDU (Harper, Jeff)
Fri Aug 21 12:29:16 2009
From: "Harper, Jeff" <Jeff.Harper@Suddenlink.com>
To: "Gaynor, Jonathan" <Jonathan.Gaynor@fccc.edu>, "nanog@nanog.org"
<nanog@nanog.org>
Date: Fri, 21 Aug 2009 11:28:32 -0500
In-Reply-To: <437B9D1DC8417B428C3C5E0FCBB7E55A059AA2A6@rex1.ritf.fccc.edu>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
Hi Jon,
If I personally saw it, I wouldn't bother since I would assume there would =
be a method to your madness. ;-)=20=20
Jeff
-----Original Message-----
From: Gaynor, Jonathan [mailto:Jonathan.Gaynor@fccc.edu]=20
Sent: Friday, August 21, 2009 10:58 AM
To: nanog@nanog.org
Subject: Redundancy & Summarization
My institution has a single /16 spread across 2 sites: the lower /17 is
used at site A, the upper /17 at site B. Sites A & B are connected
internally. Currently both sites have their own ISPs and only advertise
their own /17's. For redundancy we proposed that each site advertise
both their own /17 and the whole /16, so that an ISP failure at either
site would trigger traffic from both /17s to reconverge towards the
unaffected location.
My worry/question: will carriers down the line auto-summarize my
advertisements into a single /16, resulting in a 'load sharing' while
both sites are active? If you're a backbone carrier and you saw x.x/16
and x.x/17 (or x.x/16 and x.x.128/17) being advertised from the same
peer would you drop the longer match?
Regards and thanks,
Jon Gaynor, Senior Network Engineer
Fox Chase Cancer Center
(215) 214-4267, jonathan.gaynor@fccc.edu
