Is it safe to upgrade CUCM and CUC during work hours?

[lisacoody]

Hey y'all,

I am planning a simple upgrade of CUCM (pub and sub) and CUC (standalone) from version 11.0.1 to 11.5.1 and have a question. I would like to know if it is safe to perform the upgrade process during work hours, then do the switch version part during a maintenance window? 

Thanks in advance!!

Lisa

[Jaime Valencia · Accepted solution]

Assuming you do not have high CPU usage in your servers, it should be fine.

However, it's always recommended to perform the upgrades during maintenance windows.

Bear in mind that any changes between the time you upgrade and the time you switch, will be lost.

[lisacoody]

Thank you very much for your reply, Jaime! Because I'm a very cautious person, I decided to perform the upgrades during a maintenance window instead of during working hours. Both Unity Connection and Call Manager services remained available during the upgrades and only went down during the period when I switched versions.

I really appreciate your assistance - you are a truly  an asset to the Cisco support forum community!