In preparation for configuring your SAN and setting up your ESXi system to use SAN storage, review the requirements and recommendations.

  • Make sure that ESXi systems support the SAN storage hardware and firmware combinations you use. For an up-to-date list, see the VMware Compatibility Guide.

  • Configure your system to have only one VMFS volume per LUN.

  • Unless you are using diskless servers, do not set up the diagnostic partition on a SAN LUN.

    If you use diskless servers that boot from a SAN, a shared diagnostic partition is appropriate.

  • Use RDMs to access raw disks. For information, see Raw Device Mapping.

  • For multipathing to work properly, each LUN must present the same LUN ID number to all ESXi hosts.

  • Make sure that the storage device driver specifies a large enough queue. You can set the queue depth for the physical HBA during a system setup. For information on changing queue depth for HBAs and virtual machines, see the vSphere Troubleshooting documentation.

  • On virtual machines running Microsoft Windows, increase the value of the SCSI TimeoutValue parameter to 60. With this increase, Windows can tolerate delayed I/O resulting from a path failover. For information, see Set Timeout on Windows Guest OS.