I'm trying to extend a drive in ESX3.5. This is an NTFS volume that serves as a primary boot for Windows 2003, but that shouldn't matter. Here's what I do within VMWare Infrastructure:

  1. Right-click VM, select "Edit Properties"
  2. Select Hard Disk 1, it says Disk Size (GB): 33.91, Maximum size: 256 (GB).
  3. I can verify that on the data store there's several TB available, unused.
  4. I increase the size "New Size" to 60 GB, note: made sure it was GB and not MB
  5. Boot to a GParted Live ISO
  6. Parition shows a very small (8MB) unallocated amount. It is as if the size hasn't changed.

I'll power off the VM, notice that the size is still 33.91GB, as if my changes aren't taking place. Strange, so I'll increase the "New Size" box again, click Ok ... go back to the Edit Settings and the size is still 33.91GB. "Reconfigure Virtual Machine" shows completed with a green flag, no errors but it is obviously not working. What can I do?

  • What's the size of the datastore where the VM is located? – Vick Vega Apr 25 '11 at 15:18

You could try extending the disk through the command line.

vmkfstools -X 60G /path/to/drive.vmdk

As well you could look in the vmware log file for any error messages.


I hate answering my own question. But here's what I did:

  1. Back up the volume.
  2. Remove the drive then add it back.
  3. This now allowed me to increase the size of the disk ...
  4. BUT! When I rebooted (without going through gpart first, just to see if it would boot), I received a "Cannot open disk .... Reason: The parent virutal disk has been modified since the child was created."
  5. The only snapshot I could get working was the very first one when the physical machine was converted to a virtual machine.
  • I was going to say that it was a problem with a snapshot. You can't make changes to a VMs disks when snapshots exist. I've run across this a couple times when other sysadmins have created a snapshot but not cleaned up after themselves. – Scott Keck-Warren May 2 '11 at 14:55

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