CUCM 11.5 to 12.5 upgrade - need to increase VM resources

[lisacoody]

I have a two-node cluster on version 11.5.1 that I'd like to upgrade to 12.5.1. My current VMs have 2 vCPU, 4 GB memory, and 80 GB hard disk. In RTMT I keep getting alerts for low water mark hits and high memory usage so since I have the resources, I'd like to increase my VM reservations for version 12.5 to 2 vCPU, 8 GB memory, and 110 GB hard disk. My question is how to do this. 

Any advice is greatly appreciated!

Lisa

[Jaime Valencia]

That is explained in the upgrade guide, it's part of the mandatory reading when performing an upgrade.

Mandatory reading regardless of what upgrade path you choose, all for target version 
 
A) Upgrade and migration guide
B) Release Notes 
C) Compatibility matrix (depending on product might be a standalone doc, or within any of the other docs I mention) 
D) README from ova
E) HW/ESXi compatibility 
 
After reading all of the above, you'll have all the information to plan the upgrade. 

[lisacoody]

Thank you for your comments, Jaime. I have been reading the upgrade guide, but the wrong section. I was looking at the steps for a direct refresh upgrade instead of a direct migration. I'm going to go back through the documentation and see if I can find the answer to my question.

[Roger Kallberg · Accepted solution]

AFAIK you can not increase the size of your hard drive in a single disk setup of CM.

To do that you’ll need to create a new VM and use the bigger size option OVA, install CM on it, with exactly the same setup as you current CM, down to IP address, name and version. Once you have it running you’ll need to do a restore from DRS backup to get your data back.

For the memory part it’s much simpler, just turn off the CM node and change the settings of the VM in vCenter and start the VM again.

[lisacoody]

Thank you for your advice, Roger. That is what I'm thinking I need to do, I just wasn't sure.