We use netbackup for backups. It utilizes vmtools for snapshotting as a part of its backup process. We have been having issues with backups failing and with our vmtools slipping into the not running state. And subsequently, our backups failing with the following error showing up under Tasks in vCenter:
It turns out the version of vmtools that comes with ESXi v6 u2 (10.0.6) is buggy. If you upgrade to version 10.0.9 it resolves this issue – it is listed in the release notes under Attempts to take a quiesced snapshot in a Windows Guest OS fails.
We have not installed this version yet to confirm it fixes it but I figured I would share as we have been wasting time trying to troubleshoot and fix vmtools when we have the buggy version.
FYI, if you’re on ESXi v6 u2, your VM’s will show as ‘up to date’ and will be vmtools version 10.0.6. You will have to install 10.0.9 manually. We are testing whether we can just install it on the host and then run automatic upgrade again.