Use the vmkfstools command to create a VMFS datastore or a scratch partition. 

-C|--createfs [vmfs5|vmfs6|vfat]

This option creates the VMFS datastore on the specified SCSI partition, such as disk_ID:P. The partition becomes the head partition of the datastore. For VMFS5 and VMFS6, the only available block size is 1 MB.

You can specify the following suboptions with the -C option.

  • -S|--setfsname - Define the volume label of the VMFS datastore you are creating. Use this suboption only with the -C option. The label you specify can be up to 128 characters long and cannot contain any leading or trailing blank spaces.
    Note: vCenter Server supports the 80 character limit for all its entities. If a datastore name exceeds this limit, the name gets shortened when you add this datastore to vCenter Server.

    After you define a volume label, you can use it whenever you specify the VMFS datastore for the vmkfstools command. The volume label appears in listings generated for the ls -l command and as a symbolic link to the VMFS volume under the /vmfs/volumes directory.

    To change the VMFS volume label, use the ln -sf command. Use the following as an example: 
    ln -sf /vmfs/volumes/UUID /vmfs/volumes/datastore

    datastore is the new volume label to use for the UUID VMFS.

    Note: If your host is registered with vCenter Server, any changes you make to the VMFS volume label get overwritten by vCenter Server. This operation guarantees that the VMFS label is consistent across all vCenter Server hosts.
  • -Y|--unmapGranularity #[bBsSkKmMgGtT] - This suboption applies to VMFS6 only. Define granularity for the unmap operation. The default granularity is 1 MB. As with the block size, enter the unit type.
  • -O|--unmapPriority <none|low|medium|high> - This suboption applies to VMFS6 only. Define the priority for the unmap operation.

Example for Creating a VMFS File System

This example illustrates creating a VMFS6 datastore named my_vmfs on the naa.ID:1 partition. 

 ~ vmkfstools -C vmfs6 -S my_vmfs /vmfs/devices/disks/naa.ID:1