4900M BGP ASN Number <1-65535> limit.

[davidvanrensburg]

Hello

we are using a 4900M as a peering device running bgp.

We wanted to setup a session today and realised that the peer had a number higher than the above.

as far as I can see by googleing we dont have 4 byte BGP ASN Support ? Is that correct ?

The second question is am I forced to move to ver 15.x ?

we are running :

ter-cpt-01#sh ver

Cisco IOS Software, Catalyst 4500 L3 Switch Software (cat4500e-ENTSERVICESK9-M), Version 12.2(54)SG, RELEASE SOFTWARE (fc3)

Technical Support: http://www.cisco.com/techsupport

Copyright (c) 1986-2010 by Cisco Systems, Inc.

Compiled Sun 27-Jun-10 09:28 by prod_rel_team

Image text-base: 0x10000000, data-base: 0x12E09514

ROM: 12.2(44r)SG10

Im quite scared to upgrade the image of this device as its a very important device on our network and ive heard that the romon may not support version 15 ?

Ive looked for a ver 12.2 that supports bgp 4 byte it seems like it doesnt exist but I find the tools like feature navigator and version numbers really complicated.

A bit of guidance would be highly appreciated.

Thanks.

DAVID.

[Georg Pauwen]

Hello David,

you don't need to upgrade, as new and old BGP speakers, that is, 4-byte capable and non-capable speakers, can still communicate. A special ASN, 23456, is used. Check the link below for an example:

http://stuff.baturin.org/post/9205042521

[davidvanrensburg]

Hello.

Thats good news thank you for pointing that out. Long term do you suggest upgrading? We wont be able to do many filtering by asn etc as that 23456 is a placeholder but certainly great for the mean time.

What version do you suggest upgrading to ? Are there any issues with rommon versions and version 15 ?

[Georg Pauwen · Accepted solution]

Hello,

the only thing you cannot do right now is anything AS-PATH related, since you cannot see the path. So unless you really need AS-path related policies, I would not see the need to upgrade. That said, if you do upgrade, it is usually recommended to do both at the same time, ROMMON and IOS upgrade. Obviously that involves downtime...

[Iulian Vaideanu]

ROMMON version 12.2(44r)SG10 is the latest available for C4900M, so it should obviously support whatever recent IOS released so far...  we have five 4900Ms with ROM 12.2(44r)SG10 happily running 15.1(2)SG* IOSes.

[davidvanrensburg]

ROM: 12.2(44r)SG10

so that means our rommon is up to date.

If i upgrade to ver 15 do you need a special license ? Also would the twingig converters still work fine ?

[Iulian Vaideanu]

We also run quite a few of those (twingigs) in our 4900Ms...

As for the license part, I'm pretty sure you don't need any - I can't find any "license" commands available, and as far as I know the only difference in feature sets is made by the IOS image (entservices and ipbase, and lanbase up to 15.0).