Using affordable shared storage to maximize high availability and fault tolerance in VMware environments
Utilizing a shared SAN allows all vSphere servers to see the same storage, enabling movement of VMs and applications across redundant infrastructure. This architecture opens up tremendous flexibility and IT managers can move applications without impacting user access or uptime. This is a lifesaver when it comes to maintenance; move a VM and application, perform maintenance, migrate back–without users even noticing.
Without a SAN, VMs are limited to one physical server and direct-attached storage and are subject to downtime for maintenance or extended downtime in the event of a failure.