VMFS datastores serve as repositories for virtual machines. You can set up VMFS datastores on any SCSI-based storage devices that the host discovers, including Fibre Channel, iSCSI, and local storage devices.

Note: You cannot create VMFS3 datastores on the ESXi hosts. Existing VMFS3 datastores continue to be available and usable, so that you can migrate your virtual machines to VMFS5 or VMFS6 datastores.


  1. Install and configure any adapters that your storage requires.
  2. To discover newly added storage devices, perform a rescan. See Storage Rescan Operations.
  3. Verify that storage devices you are planning to use for your datastores are available. See Storage Device Characteristics.


  1. In the vSphere Web Client navigator, select Global Inventory Lists > Datastores.
  2. Click the New Datastore icon.
  3. Enter the datastore name and if necessary, select the placement location for the datastore.
    The vSphere Web Client enforces a 42 character limit for the datastore name.
  4. Select VMFS as the datastore type.
  5. Select the device to use for your datastore.
    Important: The device you select must not have any values displayed in the Snapshot Volume column. If a value is present, the device contains a copy of an existing VMFS datastore. For information on managing datastore copies, see Managing Duplicate VMFS Datastores.
  6. Specify the datastore version.
    Option Description
    VMFS6 This option is default for 512e storage devices. The ESXi hosts of version 6.0 or earlier cannot recognize the VMFS6 datastore. If your cluster includes ESXi 6.0 and ESXi 6.5 hosts that share the datastore, this version might not be appropriate.
    VMFS5 This option is default for 512n storage devices. VMFS5 datastore supports access by the ESXi hosts of version 6.5 or earlier.
  7. Define configuration details for the datastore.
    1. Specify partition configuration.
      Note: The required minimum size for a VMFS6 datastore is 2 GB.
      Option Description
      Use all available partitions Dedicates the entire disk to a single VMFS datastore. If you select this option, all file systems and data currently stored on this device are destroyed.
      Use free space Deploys a VMFS datastore in the remaining free space of the disk.
    2. If the space allocated for the datastore is excessive for your purposes, adjust the capacity values in the Datastore Size field.
      By default, the entire free space on the storage device is allocated.
    3. For VMFS6, specify the block size and define space reclamation parameters.
      Option Description
      Block size The block size on a VMFS datastore defines the maximum file size and the amount of space the file occupies. VMFS6 supports the block size of 1 MB.
      Space reclamation granularity Specify granularity for the unmap operation. Unmap granularity equals the block size, which is 1 MB.

      Storage sectors of the size smaller than 1 MB are not reclaimed.

      Space reclamation priority Select one of the following options.
      • Low (default). Process the unmap operations at a low rate.
      • None. Select this option if you want to disable the space reclamation operations for the datastore.
  8. In the Ready to Complete page, review the datastore configuration information and click Finish.


The datastore on the SCSI-based storage device is created. It is available to all hosts that have access to the device.