Re: Pervasive BGP and routing loops.

Radha Gowda <rxg@proteon.com> Tue, 23 May 1995 12:44 UTC

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From: Radha Gowda <rxg@proteon.com>
Subject: Re: Pervasive BGP and routing loops.
To: toconnor@bbn.com
Date: Tue, 23 May 1995 08:31:23 -0400 (EDT)
Cc: bgp@ans.net
In-Reply-To: <199505222255.AA10562@interlock.ans.net> from "toconnor@BBN.COM" at May 22, 95 06:53:25 pm
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Tony and Tim,

Thank you both for your responses.  It's my lack of understanding of BGP
that made me believe that you can not advertise a route unreachable unless
you have lost all paths to it.  The following should take care of my 
problem.

Radha

> But if R3 decides the "best route" is via R4, then shouldn't it send an
> UNREACHABLE update to R4 ? In other words, if I advertise path X to any
> route R, and I then learn a better path Y to route R, then I forward the
> new path as a replacement OR (in this case, because of your stricture not
> to reflect routes back to the advertiser) I should send an UNREACHABLE.