Data/Storage Virtualisation

Managing disk storage was once simple: If we needed more space, we got a bigger disk drive. But data storage needs grew, so we started adding multiple disk drives. Finding and managing these became harder and took more time, so we developed RAID, network-attached storage and storage-area networks. Still, managing and maintaining thousands of disk drives became an ever more onerous task.

The latest answer to this dilemma is storage virtualisation, which adds a new layer of software and/or hardware between storage systems and servers, so that applications no longer need to know on which specific drives, partitions or storage subsystems their data resides. Administrators can identify, provision and manage distributed storage as if it were a single, consolidated resource. Availability also increases with storage virtualisation, since applications aren't restricted to specific storage resources and are thus insulated from most interruptions.

Also, storage virtualisation generally helps automate the expansion of storage capacity, reducing the need for manual provisioning. Storage resources can be updated on the fly without affecting application performance, thus reducing downtime.