CUCM 8.5 ans ISR 28XX

[jeremie.boisset]

Hi,

I want to upgrade a CUCM to a 8.5 release.

My clients has lots of ISR gateways 28XX.

Do I have to upgrade them to 15.X IOS and so to uprade the memories or is it possible to keep the routers in IOS 12.x ?

I precise that I don't need 8.5 new features on remote sites.

Thank you for your help.

Regards,

[Logan Gaffney]

Jeremie,

Based on the CUCM Release Matrix:

http://www.cisco.com/en/US/partner/docs/voice_ip_comm/uc_system/unified/communications/system/versions/IPTMtrix.html

For 28XX ISR's, it is recommended that you upgrade to 15.1(3)T

Regarding whether or not you HAVE to upgrade,  the call signalling should work fine on 12.x.  However if you were to run into an issue, one of the first steps towards resolution would be to get you on the recommended version of code as referenced by the above documentation.

[Jonathan Schulenberg]

I would use some severe caution before upgrading IOS to 15.1(3)T. Read the known defects; there are several severity one issues. Also pay close attention to the increased memory requirements of the late 12.4T and 15.x trains.

It really depends what you are using the router for. SIP or H.323 should work the same as always as they are well-known standards. CUCM is supposed to downgrade MGCP based on the protocol version the router is running. SCCP is your wildcard, once in a while you'll have to upgrade to an IOS version that has a newer SCCP version for things to work.

[JOHNY JOSEPH]

HI,

Will the below IOS version for 2851 router will work with CUCM version 8.5

Cisco IOS Software, 2800 Software (C2800NM-ADVIPSERVICESK9-M), Version 12.4(9)T7, RELEASE SOFTWARE (fc3)

Thanks,