[19660] in North American Network Operators' Group
Re: BGP 4, auth error question.
daemon@ATHENA.MIT.EDU (Ben Black)
Mon Sep 21 11:52:42 1998
Date: Fri, 18 Sep 1998 17:35:44 -0400
From: Ben Black <black@cypher.net>
To: Chris Morrell <chrism@uunet.ca>, Harold Willison <harold@agis.net>
Cc: nanog@merit.edu
In-Reply-To: <Pine.GSO.3.96.980918170828.7395J-100000@troll.uunet.ca>; from Chris Morrell on Fri, Sep 18, 1998 at 05:14:28PM -0400
On Fri, Sep 18, 1998 at 05:14:28PM -0400, Chris Morrell had most eloquently written:
>
> The Cisco is probably running IOS 11.1(20)CC. This version has a bug in
> it that assumes the other side will understand its request to negotiate
> MBGP (which there is no RFC for and which seems to be Cisco proprietary at
> this point).
>
actually, i think the bug relates to Capabilities Negotiation, which is a
draft RFC at this point. there is great irony in capabilities negotiation
causing a BGP session to reset because it was created specifically to
avoid connection resets from unknown Optional Parameters in an OPEN message.
> The BGP session will come up with a Cisco which can't run MBGP, but it
> doesn't seem to work for other routers. (notably routers using gated
> derived code.
>
> Changing the IOS will fix the problem, but the better short term thing to
> do is to have the Cisco side add the following line to their BGP
> configuration for your connection:
>
> neighbor AA.BB.CC.DD dont-capability-negotiate
>
the real bug is not that cisco implemented capability negotiation incorrectly,
but that it is on by default long before anyone else has implemented it.
> If you want more details and the actual Cisco Bug ID, I can find that for
> you.
>
> Chris
>
ben
