Win2k8-R2 VM's are powering down by themselves!

[Cannoli]

I recently modified several Windows 2008R2 Enterprise VM's to have 6 CPU's/2 Cores per CPU (12vCPU's) and 10GB of RAM from 4 vCPU's/1 Core per CPU and 6 GB of RAM.  Now I'm seeing that many of the VM's are simply powering down without warning.  No errors in the WIndows Event logs and only a message in vCenter events for the VM that says "Alarm 'Virtual Machine Memory Usage went from Green to Gray'" and just before that is says "Virtual Machine on vsphere-serverxxx.xxxx.xxxx.com is powered off"

What's going on?  The physical hosts have more then enough resources to meet the new VM sizing.  They are 24 core with 48GB of RAM.

[peetz]

Are these VMs shut down cleanly or just powered off?

You should able to find this out by looking at the Windows eventlog. If they are cleanly shut down you may also be able to see why this happened in the Windows eventlog. If they are just powered off then check the logfile ot the VM (vmware.log in the VM's location on the datastore).

Also check the vCenter eventlog of the VMs and finally the vmkernel.log of the host that ran the VM before it powered off.

[Datto]

Guesses:

1) ran out of storage space.

2) Trial license for the O/S has expired.

Datto

[Cannoli]

Problem identified!

After upgrading the vCPU and RAM in 328 Win2k8R2 VM's, I was (or thought) sure to boot them up then reboot them after VMware Tools was up for the new hardware drivers and configuration in the OS to be complete.  Apperently this overall process took longer on about 1/3 of the virtual machines so after my forced OS restart (gracefully) the new hardware still wasn't installed completely.  Win2k8R2 gracefully shut itself down after the hardware install was complete so I saw what I thought was a random shutdown of many VM's.

In this case, patience pays dividends in the hair loss avoiding department!