To convert a virtual machine base disk from thick to thin provisioning by changing the datastore and performing storage vMotion
- Right-click the virtual machine and select Migrate.
- Select Change storage only and click Next.
- In the next window, select the option configure per disk and click .
- Select the disk in question which needs to undergo the modification and click Configure
- Select the destination storage, besides Select virtual disk format select Thin Provision and click confirm
- Check if the Disk Format has the correct option and click next
- Review the information on the Review Selections page and click Finish.