The HP Virtual SAN Appliance software is a VMware certified SAN/storage device & virtual appliance that provides complete SAN functionality for VMware Infrastructure without external SAN hardware. By virtualizing the internal disk capacity of the server running VMware ESX, the VSA software eliminates the need for external shared storage required to implement the advanced features of VMware Infrastructure. Multiple VSAs running on multiple VMware ESX hosts create a clustered pool of storage with the ability to replicate data across the hosts allowing volumes to stay on-line in the event of a server failure. VSA software deployed at remote sites is managed as virtual storage nodes using the same centralized management console used to manage your HP SANs.