Each virtual machine or virtual machine template requires a folder or directory for its virtual disks and files. When you create a virtual machine or template to deploy to the vCenter Server inventory, select a datastore or datastore cluster for the virtual machine's configuration and other files and all of the virtual disks. Each datastore can have a different size, speed, availability, and other properties.

The amount of free space in the datastore is always changing. Ensure that you leave sufficient space for virtual machine creation and other virtual machine operations, such as growth of sparse files, snapshots, and so on. To review space utilization for the datastore by file type, see the vSphere Monitoring and Performance documentation.

Thin provisioning lets you create sparse files with blocks that are allocated upon first access, which allows the datastore to be over-provisioned. The sparse files can continue growing and fill the datastore. If the datastore runs out of disk space while the virtual machine is running, it can cause the virtual machine to stop functioning.


  1. Select the format for the virtual machine's disks.
    Option Action
    Same format as source Use the same format as the source virtual machine.
    Thick Provision Lazy Zeroed Create a virtual disk in a default thick format. Space required for the virtual disk is allocated during creation. Any data remaining on the physical device is not erased during creation, but is zeroed out on demand at a later time on first write from the virtual machine.
    Thick Provision Eager Zeroed Create a thick disk that supports clustering features such as Fault Tolerance. Space required for the virtual disk is allocated at creation time. In contrast to the thick provision lazy zeroed format, the data remaining on the physical device is zeroed out during creation. It might take longer to create disks in this format than to create other types of disks.
    Thin Provision Use the thin provisioned format. At first, a thin provisioned disk uses only as much datastore space as the disk initially needs. If the thin disk needs more space later, it can grow to the maximum capacity allocated to it.
  2. (Optional) Select a storage policy from the VM Storage Policy drop-down menu.
    Storage policies specify storage requirements for applications that run on the virtual machine.
  3. Select a datastore location for the virtual disk.
    Option Action
    Store the virtual disk and virtual machine configuration files in the same location on a datastore.

    Select Store with the virtual machine from the Location drop-down menu.

    Store the disk in a separate datastore location. Select Browse from the Location drop-down menu, and select a datastore for the disk.
    Store all virtual machine files in the same datastore cluster.
    1. Select Browse from the Location drop-down menu and select a datastore cluster for the disk.
    2. (Optional) If you do not want to use Storage DRS with this virtual machine, select Disable Storage DRS for this virtual machine and select a datastore within the datastore cluster.
  4. Click Next.