As part of our license for VMWare’s Virtual Center Management Server, we get a copy of the VMWare Converter, Enterprise Edition, which allows trivial migration of any Windows physical host to virtual hardware. Additionally, the Converter can…well…convert from other virtual machine formats, including other VMWare products.
An interesting side-effect of this is that you can re-size your VMDKs (virtual disk image “files”). SAN space is expensive, so when we were looking to deploy some new VMs in our test environment, and noting that they only took up maybe 15% of the allocated disk space for them, it occurred to me that we could “clone” them by using the Converter, and simultaneously shrink them.
Normally this is something that you could do with ESX’s vmkfstools command-line utility, which allows you to shrink or grow these virtual disks. Unfortunately, Windows will sometimes complain when you try to resize the system/boot partition.
Here’s what it looks like:
Notice the “New Disk Space” drop-down; a 20GB VMDK, after conversion, will now be only 10GB! By choosing the same Virtual Center installation as the source and destination, you can effectively and conveniently resize your system partition. Don’t forget to remove the “old” VM (the source in this case), otherwise you’re not really saving any disk space!








