The great thing about SSDs is the performance. You can run multiple virtual machines off a single drive and they don’t skip a beat. The only downfall to SSDs is the capacity. 256GB on the Crucial M4 in my ESXI box isn’t a whole lot to play with.
When I initially setup the virtual machines on my box, I threw them onto spinning disks. I had the extra space, and a thick provisioned disk generally performs better than thin. Moving these disks to an SSD would result in only being able to spin up a few machines before reaching capacity. I really didn’t want to walk through creating new VMs and reconfiguring as well, so I started researching.
With vCenter, all you really have to do is migrate the VM to a new disk, and when migrating, select the provisioning option of thin. Without vCenter however, that option isn’t available with the free standalone product. There are two workarounds however, the first being to SSH into the machine and use the VMKFSTools to convert the disks. That’s great, but there’s room for some error. The second way is the way I chose, which is to use the VMWare Standalone Converter. It allows me to basically clone the machine from spinning disk onto the new SSD datastore, thin provision in the process, then delete the old machine.
I’m going to be converting my Backtrack install from the server to the server, and here’s a step by step.
Step one is to load up the vCenter standalone converter, and select the convert option. You’ll get a wizard pop up that lets you start. Select VMWare Infrastructure Virtual Machine from the drop down, then log into your ESXI box.
Step two is to select from the list the machine you want to convert. I’m going to select my Backtrack4 virtual machine.
Step three is to select your destination. From the drop down, select VMWare Infrastructure Virtual Machine, the log into your ESXI box.
Step four is to create a name for your converted machine. I’m using Backtrack4_thin
Step five is to select your location. In this case, from the datastore dropdown, I selected CrucialSSD, which is where I want this machine to go.
Step six is to edit the data to copy field. From the type dropdown, select thin. Then select next, or edit any other settings, like memory or vCPU count.
Step seven is to review and select finish. Depending on how fast the datastore is, and how large the conversion will be, it can take anywhere from a few minutes to a few hours.
After the conversion is finished, log into your ESXI box and verify the new virtual machine is functional. Once you’ve verified functionality, delete the original from disk.