When setting up storage for ESXi hosts, before creating VMFS datastores, you must decide on the number and size of LUNS to provision. You can experiment using the adaptive scheme.


  1. Provision a large LUN (RAID 1+0 or RAID 5), with write caching enabled.
  2. Create a VMFS on that LUN.
  3. Create four or five virtual disks on the VMFS.
  4. Run the applications to determine whether disk performance is acceptable.


If performance is acceptable, you can place additional virtual disks on the VMFS. If performance is not acceptable, create a new, large LUN, possibly with a different RAID level, and repeat the process. Use migration so that you do not lose virtual machines data when you recreate the LUN.