Installation guide

C H A P T E R 9 Storage and File Systems
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Using Storage Area Networks with ESX
Server
VMware ESX Server can be used effectively with storage area networks (SANs). ESX
Server supports Qlogic and Emulex host bus adapters, which allow an ESX Server
computer to be connected to a SAN and to see the disk arrays on the SAN.
The SCSI configuration information contained in this section also applies to Fibre
Channel adapters, but note that FC adapters may require additional configuration as
well.
For information on supported SAN hardware, download the VMware ESX Server SAN
Compatibility List from the VMware Web site at www.vmware.com/support/esx2.
Understanding Storage Arrays
Large storage systems (also known as disk arrays) combine numerous disks into arrays
for availability and performance. Typically, a collection of disks is grouped into a
Redundant Array of Inexpensive Disks (RAID) array to protect the data by eliminating
disk drives as a potential single point of failure.
Disk arrays carve the storage RAID set into logical units (LUNs) that are presented to
the server in a manner similar to an independent single disk. Typically, LUNs are few in
number, relatively large, and fixed in size.
You can create LUNs with the storage management application of your disk array.
Installing ESX Server with Attached SANs
We recommend that you install ESX Server software on a local SCSI disk.
Caution: Be sure that all Fibre Channel adapters (QLogic or Emulex) are detached
from the SAN during ESX Server installation. If they are not disconnected, SAN disks
are often displayed first in the list of drives displayed during installation. This may
cause confusion when the service console is being installed.
In addition, we recommend that all Fibre Channel adapters are dedicated exclusively
for the virtual machines. Even though these FC adapters are dedicated to virtual
machines, the LUNs on the SANs are visible to system management agents on the
service console.