How to reclaim thin VMDK space for Windows guest

1. Download "sdelete" and put it on VM guest.

2. Execute "sdelete -z c:" (if VM guest had other driver letter, should do them all)

3. After finished, power-off VM guest.

4. SSH to the host which VM guest is on it.

5. Change the volume where VM guest is on it.

6. "ls -lh *.vmdk" to check the vmdk size.

7. "du -h *.vmdk" to see the vmdk real size.

8. "vmkfstools -punchzero VM.vmdk"

9. After above job done, execute "du -h *.vmdk" again to check the size.

10. Power-on the VM guest and check the storage usage on vSphere Client.

Cloning and converting virtual machine disks with vmkfstools

vmkfstools -i <input> <output> -d <format>

Convert HD type to thin-provision
1. SSH to VM host.
2. Shutdown the virtual machine.
3. vmkfstools -i "guest.vmdk" "new_guest.vmdk" -d thin
4. Add new HD and point to the "new_guest.vmdk" under "Edit setting"
5. Power-on the virtual machine.
6. Delete the "guest.vmdk" file.

http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1028042

How to increase HD size for Windows XP guest in ESXi

1. SSH to VM host.
2. Power-off the guest.
3. vmkfstools -X xxG /vmfs/volumes/"Datastore"/"VM guest"/"VM guest".vmdk
4. Power-on the guest.
5. Use GParted to extend the size for the filesystem of virtual machine.