Well this one certainly caused me some heartache. I’m posting it here in hopes that it helps someone else.
I don’t remember when exactly it started or why, but I noticed that when I tried to shut down my virtual machines, they would lock up. I could not tell what was wrong with them and if I tried to use VM -> Power -> Off they would get to 95% and then lock up.
I would end up having to reboot the VMWare server to get them back online.
While doing some VM upgrading, this was happening a lot. It got frustrating enough for me to start seriously trying to figure out the problem.
Reviewing the VMWare server logs showed a lot of “Sync CR” messages in the log. These indicate reservation conflicts for SCSI control in VMWare.
It seemed that for some reason, my problem was not VMWare, but the iSCSI initiator on Openfiler.
For me this issue was resolved by restarting the iSCSI initiator service like this:
/etc/init.d/open-iscsi restart
This should be a last resort though, since, without properly shutting down your VMs, it WILL seriously anger the VMWare server and probably screw up any virtual machines running on the iSCSI drive.