System information

ESX Boot from SAN Requirements
When you have SAN storage configured with your ESX system, you can place the ESX boot image on one of
the LUNs on the SAN. This configuration must meet specific criteria.
To enable your ESX system to boot from a SAN, your environment must meet the requirements listed in
Table 3-1.
Table 3-1. Boot from SAN Requirements
Requirement Description
ESX system
requirements
ESX 3.x or later is recommended. When you use the ESX 3.x system or later, RDMs are supported
in conjunction with boot from SAN. For an ESX Server 2.5.x system, RDMs are not supported in
conjunction with boot from SAN.
HBA requirements The HBA BIOS for your HBA FC card must be enabled and correctly configured to access the boot
LUN.
The HBA should be plugged into the lowest PCI bus and slot number. This allows the drivers to
detect the HBA quickly because the drivers scan the HBAs in ascending PCI bus and slot numbers,
regardless of the associated virtual machine HBA number.
Boot LUN
considerations
n
When you boot from an active/passive storage array, the SP whose WWN is specified in the
BIOS configuration of the HBA must be active. If that SP is passive, the HBA cannot support
the boot process.
n
To facilitate BIOS configuration, mask each boot LUN so that only its own ESX system can see
it. Each ESX system should see its own boot LUN, but not the boot LUN of any other ESX
system.
SAN considerations
n
SAN connections must be through a switched topology if the array is not certified for direct
connect topology. If the array is certified for direct connect topology, the SAN connections can
be made directly to the array. Boot from SAN is supported for both switched topology and
direct connect topology if these topologies for the specific array are certified.
n
Redundant and nonredundant configurations are supported. In the redundant case, ESX
collapses the redundant paths so that only a single path to a LUN is presented to the user.
Hardware- specific
considerations
If you are running an IBM eServer BladeCenter and use boot from SAN, you must disable IDE
drives on the blades.
Installation and Setup Steps
This topic provides an overview of installation and setup steps that you need to follow when configuring your
SAN environment to work with ESX/ESXi.
Follow these steps to configure your ESX/ESXi SAN environment.
1 Design your SAN if it is not already configured. Most existing SANs require only minor modification to
work with ESX/ESXi.
2 Check that all SAN components meet requirements.
3 Perform any necessary storage array modification.
Most vendors have vendor-specific documentation for setting up a SAN to work with VMware ESX/ESXi.
4 Set up the HBAs for the hosts you have connected to the SAN.
5 Install ESX/ESXi on the hosts.
6 Create virtual machines.
7 (Optional) Set up your system for VMware HA failover or for using Microsoft Clustering Services.
8 Upgrade or modify your environment as needed.
Chapter 3 Requirements and Installation
VMware, Inc. 31