TIL: You cannot use SCSI Bus sharing with thin provisioned VMDKs
Welcome to my first “today I learned” post. These are posts about details of which I didn’t know about and discovered. Sometimes simple, sometimes complex, but hopefully informative to others.
We have a test SQL 2005 cluster in our vSphere lab that used to power on properly until we did a storage vmotion and converted the VMDK disks to thin format. When trying to power up the VM vCenter spit the following error in the event logs and popped up an error window.
Cannot power Off: VMware ESX Server cannot open the virtual disk,
clustering. Please verify that the virtual disk was created using the ‘thick’ option. Cannot open the
or one of the snapshot disks it depends on. Reason: Thin/TBZ disks cannot be opened in
The resolution to this problem is obviously simple, you can either convert the disks to thick. You can do it via the “inflate” option in the datastore browser or storage vmotion and select the thick option.
Also, if you don’t have any space left on any of your datastores to accommodate the thick disks and you really need to get one system up and running (degraded cluster), then you can always disable SCSI Bus sharing on the SCSI device and power up the VM.