I have a virtual Exchange 2003 which is residing on an Equallogic SAN. It had been working fine for a long time but last night was powered down unexpectedly. When I tried to reboot it via vSphere client it gave me a space error regarding the datastore: "Could not power VM: No space left on device."
The SAN volume was showing only about 1% free space whereas the datastore on vSphere was showing close to 40% free space. Why this difference? Aren't they supposed to show the same numbers?
I tried deleting a couple of snapshots on SAN but that didn't help. Then I called Dell tech support. They decided to increase the size of the volume on the RAID. After doing a couple of refreshes on vSphere the datastore space started showing the correct numbers close to those reported by SAN console. WHY?
At that point I tried another power on. It did power but it stayed at 95% for about 10-15 mins. WHY?
Dell techs suggested that I clean snapshots of the machine from vSphere in order not to run into space issues anymore. How can I do that without risking any damage on the virtual machine itself?