Best way to change VM Guest OS version during upgrade to 12.5

[TomMar1]

Seems wasteful to wait for UCM to boot to the new version only to shut it down to change to CentOS and boot it again.

Is there a better (less time consuming) way?

Thanks

[Roger Kallberg]

The upgrade procedure actually states that the OS on the VM should be set to CentOS 7 64 bit before the actual upgrade starts, not after as you wrote. To make the change you have to shutdown the VM, there is no other option. Even if the CM would still be on RHEL and the VM OS is set to CentOS on the VM it will boot up just fine and actually show it runs RHEL once booted up, despite the VM setting.

[TomMar1]

I only see references to modifying the network adapter prior to the upgrade not modifying the Guest OS.

[Roger Kallberg · Accepted solution]

Step 4a in section Change Virtual Machine Configuration Specifications in this document states that the OS should be changed prior to the upgrade.

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/upgrade/12_0_1/cucm_b_upgrade-and-migration-guide-1201/cucm_b_upgrade-and-migration-guide-120_chapter_01001.html

I’ve done a fair share of these updates and each time we have followed this process without any issues.

[TomMar1]

I guess I should have specified the version I was upgrading from being 11.5.  I jumped to 12.5, I guess I should have looked at the 12.0 upgrade guide first, not 12.5.

Thank you

As you pointed it it works fine, to modify post upgrade.

[Roger Kallberg]

I wrote prior, not post. If you did not change it prior you can do it post, but it’s not as stated in the upgrade process guide.

[Nithin Eluvathingal]

Changing guest os

Prerequisites

Power off the virtual machine.

Procedure

1. In the VMware Host Client inventory, right-click the virtual machine and select Edit Settings.
2. Click the VM Options tab and expand General Options.
3. Select a guest operating system type and version.
4. Click Save to apply your changes.

[TomMar1]

Can you please provide a link to the upgrade guide you are referencing?

Thanks