As I have stated in a previous post, I have been trying to help out on the VMware Community Forum. One of the threads that I was able to help out on was how to convert a VMDK from thick to thin.
I have had the opportunity to do this several times in the past, but I have never needed to document. I was able to do a step by step procedure from memory for the thread, but I figured doing an actual guide might be helpful to someone else.
The first thing that you need to realize is that the VM you want to change from Thick Provision to Thin MUST be powered off before you can convert it.
Launch the VMware vCenter Converter Standalone Client software.
Click on the Convert Machine button.
That will launch the Converter wizard
By Default the Source machine will be set to Powered on VM. You will need to select the Powered off radio button which will give you to option to select VMware Virtual Machine.
Enter the Server Name or IP address, Username, and Password for the Source system and click Next
This will cause the Wizard to do a check against the Source machine to make sure that the credentials are able to access the vCenter server.
Once you are logged in, will see the your vCenter server and ESXi hosts. Click on the vCenter server, or ESXi Host to see all the VMs that are available.
Select the Powered off VM you wish to convert to thin provisioned and click Next.
Next you will need to enter the Server Name, User name and Password for the destination host. Before you ask, yes the source and destination host can be the same server, however the Virtual Machine name will need to be different.
Click Next to Continue
As I mentioned above, you will need to give the Virtual Machine a unique name, otherwise vCenter gets pretty mad.
Select the Data Center you would like to put the VM on and click Next.
Select the Host, Datastore, Virtual Hardware Version, and click Next.
NOTE: You should probably pick a different datastore that the one you used before, just to make sure that you don’t run out of space.
This will take you to the Options screen which is where you are allowed to change the Virtual Disk from Thick to Thin.
Click Edit as seen in the screen below.
This will bring up the disk configuration for this Virtual Machine.
Click on the drop down under Type and change it from Thick to Thin and then click Next.
You will then be presented with the Summary screen which you can review, and then click Finish to start the conversion.
As you can see the Job gets submitted and will run until it completes successfully
Once it completes you will see in vCenter that there is a new Virtual Machine and if you check the settings of that Virtual Machine the VMDK will be Thin Provisioned.
Thank you for stopping by, and I hope you found this post helpful and please check back later for more updates.