nanog mailing list archives

Re: Possible IOS bug w/respect to incorrect nexthop advert


From: Rodney Dunn <rodunn () cisco com>
Date: Sat, 7 Apr 2001 14:39:05 -0400


John,

Looks like they are hitting:

CSCdt06780
Externally found severe defect: Resolved (R)
Constant BGP flaps due to malformatted BGP updates

Fixed in 12.1(5.6)E and 12.1(6)E is on CCO.

I'd have to see the debugs from their side to know
for sure.

If you want to send me their email or reply
and cc them privately I'll make sure it's corrected.

rodney


On Fri, Apr 06, 2001 at 02:47:18PM -0400, John Fraizer wrote:


One of our peers recently upgraded to IOS to:

Cisco Internetwork Operating System Software
IOS (tm) RSP Software (RSP-PV-M), Version 12.1(4)E, EARLY DEPLOYMENT
RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2000 by cisco Systems, Inc.
Compiled Tue 07-Nov-00 14:23 by eaarmas
Image text-base: 0x60010958, data-base: 0x60F7C000

ROM: System Bootstrap, Version 11.1(8)CA1, EARLY DEPLOYMENT RELEASE
SOFTWARE (fc1)
BOOTFLASH: RSP Software (RSP-BOOT-M), Version 12.1(4)E, EARLY DEPLOYMENT
RELEASE SOFTWARE (fc1)



Ever since this upgrade, we've been seeing the following behavior:

When they announce prefixes to us, sometimes they get it right, as in, the
nexthop is set correctly and sometimes they get it wrong as in, the cisco
picks a random address from it's configured addresses and sends the
nexthop as that address.

Example getting it right:

2001/04/06 13:51:42 BGP: 209.115.127.21 rcvd UPDATE w/ attr: nexthop 209.115.127.21, origin i, path 6259 6461 11042 
8390 8431
2001/04/06 13:51:42 BGP: 209.115.127.21 rcvd 195.230.6.0/24
2001/04/06 13:51:42 BGP: 209.115.127.21 rcvd 195.230.7.0/24


Examples getting it wrong:

2001/04/06 13:52:10 BGP: 209.115.127.21 rcvd UPDATE w/ attr: nexthop 216.28.125.77, origin i, path 6259 3549 701 7871
2001/04/06 13:52:10 BGP: 209.115.127.21 rcvd UPDATE about 206.162.212.0/22 -- DENIED due to: non-connected next-hop;

2001/04/06 13:57:57 BGP: 209.115.127.21 rcvd UPDATE w/ attr: nexthop 216.28.126.221, origin i, path 6259 7018 14046 
14046
2001/04/06 13:57:57 BGP: 209.115.127.21 rcvd UPDATE about 216.241.140.0/23 -- DENIED due to: non-connected next-hop;



This behavior began when the peer upgraded their IOS.

Is this a documented issue or has anyone else seen this behavior?

---
John Fraizer
EnterZone, Inc




Current thread: