-- Reclamation of stranded storage capacity: This makes unused capacity available to any servers, users or applications accessing the (now) general pool. In addition, when storage is no longer needed, it becomes part of the pool again and can be used elsewhere.
-- Consolidated storage management: Applying to all storage resources, this can eliminate multiple tools and processes for different types of storage arrays and media. Consolidating storage management under one umbrella makes the environment easier to manage and provides less opportunity for both human and administrative errors.
-- Advanced storage management features: These can extend the useful life of storage devices, as well as maximize the return on investment and potentially prevent, or at least delay, additional storage purchases. For example, in a virtualized storage environment, functions such as snapshots, remote replication and thin provisioning, which may come bundled with a storage system, can be shared across arrays that don't have those features.
-- More energy-efficient operations: This can be achieved by using storage virtualization to improve disk utilization, which in turn reduces the number of physical machines while simultaneously reducing data center floor space, power and cooling requirements.
-- Non-disruptive data migration: While data migration is a core concept in executing a pragmatic and sensible tiered storage strategy, it has also long been seen as one of the most common and disruptive storage tasks. In traditional storage environments, it's not at all uncommon for users to decide that the pain is enough to prevent them from enjoying the gain! But with storage virtualization, data can be moved non-disruptively (and often even automatically) between storage tiers, further optimizing hardware infrastructure costs.
-- Reduced capital expense and total cost of ownership for storage: This is all-but guaranteed with the implementation of storage virtualization. A virtualized storage environment replaces the fragmented, dedicated DAS, SAN and NAS topologies (which -- in traditional storage worlds -- invariably operate with separate storage resources and often a unique set of management tools) with a centralized and more flexible storage pool.
Virtualized storage is essentially accomplished in the same way as the virtualization of servers: The physical controller hardware and disk resources are logically separated from the data services. With virtualized storage, a pool of flexible, consolidated resources with a common management interface is built using capacity from multiple arrays that can have different specifications and software features, and may even have come from different vendors. Because storage is not dedicated to any specific server or application, it creates a much more flexible and responsive environment while also permitting increased utilization rates.
In addition, while users may be able (using VMware vMotion or some such tool) to move a running application between servers, traditional, fixed storage won't automatically go along with the change, thus rendering it all-but pointless. Virtualizing the computing element without virtualizing the storage as well precludes the complete agility and true utility-like resource provisioning that most IT shops are looking for; if the storage cannot match what the servers can do, then the anticipated service levels cannot be met.
The economic and operational value of virtualizing storage is clear. For decades, most organizations have had a fairly cavalier attitude towards storage. It's not that IT wasn't aware of its rising costs -- it's more that it didn't see any other ways to address the problems with which it was faced. But virtualization has changed all that, demonstrating a way to operate with greater efficiency. Users that do not enthusiastically embrace it are essentially wasting money, while at the same time missing out on operational improvements that can only be gained in fully virtualized environments.
It's worth a few minutes to check that you're maximizing your potential storage virtualization benefits and not falling into the adoption gap.