6.0.1

Table Of Contents
Overview of Using ESXi with a SAN 2
Using ESXi with a SAN improves exibility, eciency, and reliability. Using ESXi with a SAN also supports
centralized management, failover, and load balancing technologies.
The following are benets of using ESXi with a SAN:
n
You can store data securely and congure multiple paths to your storage, eliminating a single point of
failure.
n
Using a SAN with ESXi systems extends failure resistance to the server. When you use SAN storage, all
applications can instantly be restarted on another host after the failure of the original host.
n
You can perform live migration of virtual machines using VMware vMotion.
n
Use VMware High Availability (HA) in conjunction with a SAN to restart virtual machines in their last
known state on a dierent server if their host fails.
n
Use VMware Fault Tolerance (FT) to replicate protected virtual machines on two dierent hosts. Virtual
machines continue to function without interruption on the secondary host if the primary one fails.
n
Use VMware Distributed Resource Scheduler (DRS) to migrate virtual machines from one host to
another for load balancing. Because storage is on a shared SAN array, applications continue running
seamlessly.
n
If you use VMware DRS clusters, put an ESXi host into maintenance mode to have the system migrate
all running virtual machines to other ESXi hosts. You can then perform upgrades or other maintenance
operations on the original host.
The portability and encapsulation of VMware virtual machines complements the shared nature of this
storage. When virtual machines are located on SAN-based storage, you can quickly shut down a virtual
machine on one server and power it up on another server, or suspend it on one server and resume operation
on another server on the same network. This ability allows you to migrate computing resources while
maintaining consistent shared access.
This chapter includes the following topics:
n
“ESXi and SAN Use Cases,” on page 28
n
“Specics of Using SAN Storage with ESXi,” on page 28
n
“ESXi Hosts and Multiple Storage Arrays,” on page 29
n
“Making LUN Decisions,” on page 29
n
“Choosing Virtual Machine Locations,” on page 30
n
“Layered Applications,” on page 31
n
“Third-Party Management Applications,” on page 32
VMware, Inc.
27