[47773] in North American Network Operators' Group
Re: BGP and aggregation
daemon@ATHENA.MIT.EDU (Stephen Griffin)
Mon May 13 17:43:31 2002
Message-Id: <200205132142.RAA11300@elektra.ultra.net>
In-Reply-To: <Pine.LNX.4.21.0205122127360.28499-100000@cpu1693.adsl.bellglobal.com> from Ralph Doncaster at "May 12, 2002 09:31:54 pm"
To: ralph@istop.com (Ralph Doncaster)
Date: Mon, 13 May 2002 17:42:49 -0400 (EDT)
From: Stephen Griffin <stephen.griffin@rcn.com>
Cc: nanog@merit.edu
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In the referenced message, Ralph Doncaster said:
>
> > BGP will discard any prefix with its own AS in the path, for loop
> > prevention. Hence, one half of the AS would still be unable to
> > reach the other half. This is why a partitioned AS is a failure
> > condition. A tunnel is a means to keep the AS nonpartitioned.
>
> I was thinking of doing iBGP over my transit connections (with a couple
> of static routes so the iBGP works) AND over my inter-city circuit. Any
> reason why this won't work?
>
> -Ralph
The loss of igp metric will make it untenable at best. Do it over a
GRE tunnel, with your regular igp (isis, ospf, eigrp, or shudder rip).
default routes have their own problems which only treat the symptoms
of a partitioned as, rather than the problem.
