Mailing List Archive: Cisco: NSP

(BGP identifier wrong) error on majority of ebgp peers

Index | Next | Previous | View Threaded

andy at nosignal

Nov 20, 2009, 8:22 PM

Post #1 of 4 (4610 views)
Permalink

(BGP identifier wrong) error on majority of ebgp peers

Hi,

I have a Cisco 6509 with SUP720-3BXL. It has over a hundred bgp peers
configured, two full tables, 4 ibgp, several peerings at an IXP.

Seemingly without a config change, there are some sessions which refuse to
establish, because of a bgp notification :

%BGP-3-NOTIFICATION: received from neighbor XXX 2/3 (BGP identifier wrong)
4 bytes XXX

The router-id has not been changed - it was using the address from Loopback
0. The router-id *is* unique, and the remote side of the peering is using
a different address.

We tried modifying the local router-id to match an address used on a
point-to-point link and clearing all sessions - same error.

This router was loaded with SXF3, moved to SXF16, moved to SXI3 - same
error seen with all three.

We removed the router bgp xx config and pasted it back in - when the
sessions established the same error was noticed.

There appears to be no commonality (eg. linecard) between the sessions
which establish, and those which don't - for example, some over the shared
ixp link establish fine, and some do not due to this router-id clash
notification.

It is always the same sessions which either come up, or refuse to come up
each time. The ibgp sessions always establish (fortunately).

Has anyone seen this before ?

Thanks
andy
_______________________________________________
cisco-nsp mailing list cisco-nsp [at] puck
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/

cwu at ffn

Nov 20, 2009, 9:23 PM

Post #2 of 4 (4622 views)
Permalink

Re: (BGP identifier wrong) error on majority of ebgp peers [In reply to]

Seems it is a Cisco bug,

..following error message: %BGP-3-NOTIFICATION: sent to neighbor 1::1 passive 2/3 (BGP identifier wrong) 4 bytes 01000003 Conditions...Workaround: Enter the clear ip bgp command. *CSCsy29534...
06 Oct 2009 - www.cisco.com/en/US/docs/ios/12_2sr/release/notes/122SRcavs1.html

-----Original Message-----
From: cisco-nsp-bounces [at] puck [mailto:cisco-nsp-bounces [at] puck] On Behalf Of Andy Davidson
Sent: Friday, November 20, 2009 8:22 PM
To: cisco-nsp [at] puck
Subject: [c-nsp] (BGP identifier wrong) error on majority of ebgp peers

Hi,

I have a Cisco 6509 with SUP720-3BXL. It has over a hundred bgp peers
configured, two full tables, 4 ibgp, several peerings at an IXP.

Seemingly without a config change, there are some sessions which refuse to
establish, because of a bgp notification :

%BGP-3-NOTIFICATION: received from neighbor XXX 2/3 (BGP identifier wrong)
4 bytes XXX

The router-id has not been changed - it was using the address from Loopback
0. The router-id *is* unique, and the remote side of the peering is using
a different address.

We tried modifying the local router-id to match an address used on a
point-to-point link and clearing all sessions - same error.

This router was loaded with SXF3, moved to SXF16, moved to SXI3 - same
error seen with all three.

We removed the router bgp xx config and pasted it back in - when the
sessions established the same error was noticed.

There appears to be no commonality (eg. linecard) between the sessions
which establish, and those which don't - for example, some over the shared
ixp link establish fine, and some do not due to this router-id clash
notification.

It is always the same sessions which either come up, or refuse to come up
each time. The ibgp sessions always establish (fortunately).

Has anyone seen this before ?

Thanks
andy
_______________________________________________
cisco-nsp mailing list cisco-nsp [at] puck
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/

The information contained in this transmission may contain privileged and confidential information. It is intended only for the use of the person(s) named above. If you are not the intended recipient, you are hereby notified that any review, dissemination, distribution or duplication of this communication is strictly prohibited. If you are not the intended recipient, please contact the sender by reply email and destroy all copies of the original message.
_______________________________________________
cisco-nsp mailing list cisco-nsp [at] puck
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/

andy at nosignal

Nov 20, 2009, 9:28 PM

Post #3 of 4 (4566 views)
Permalink

Re: (BGP identifier wrong) error on majority of ebgp peers [In reply to]

Minzhi (Catherine) Wu wrote:
> Seems it is a Cisco bug,
>
> ..following error message: %BGP-3-NOTIFICATION: sent to neighbor 1::1 passive 2/3 (BGP identifier wrong) 4 bytes 01000003 Conditions...Workaround: Enter the clear ip bgp command. *CSCsy29534...
> 06 Oct 2009 - www.cisco.com/en/US/docs/ios/12_2sr/release/notes/122SRcavs1.html

Hi,

Thanks for the mail. Clearing the session does not cause it to
re-establish (please see original message for the debugging we have tried.)

Andy
_______________________________________________
cisco-nsp mailing list cisco-nsp [at] puck
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/

andy at nosignal

Nov 25, 2009, 1:28 AM

Post #4 of 4 (4500 views)
Permalink

Re: (BGP identifier wrong) error on majority of ebgp peers [In reply to]

Andy Davidson wrote:
> Seemingly without a config change, there are some sessions which refuse to
> establish, because of a bgp notification :
> %BGP-3-NOTIFICATION: received from neighbor XXX 2/3 (BGP identifier wrong)
> 4 bytes XXX
> The router-id has not been changed - it was using the address from Loopback
> 0. The router-id *is* unique, and the remote side of the peering is using
> a different address.

Seems this could be a bug affecting the routers of our peers - when we
rebuilt the session config our side, the same behaviour was observed, but
when the remote party deletes and recreates the config facing us, the
session is allowed to establish.

Andy

_______________________________________________
cisco-nsp mailing list cisco-nsp [at] puck
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/

Index | Next | Previous | View Threaded

Interested in having your list archived? Contact Gossamer Threads