* Benefits of storage virtualization
It’s almost an axiom that one can never have too much storage capacity. Year after year enterprises generate mountains of data requiring new storage capacity. In practice, however, the average utilization of storage resources in a data center hovers between 15% and 30%.
IT managers allocate enough storage for a theoretical “peak” use, ensuring that there will not be a sudden shortage of capacity. In addition, storage is often allocated in separate silos, by application, leading to substantial inefficiencies. Unfortunately, the cost of maintaining a storage infrastructure at such low utilization (both in terms of capital spending and operational costs) is huge.
Virtualization involves the consolidation of all storage resources into a virtual storage “pool.” When an application requires storage, the storage manager can allocate capacity from the pool. Since the resources allocated to an application can be increased or decreased at will, there is no need to over-allocate storage. Furthermore, new disks can be added to the pool when new applications or increased demand are anticipated. As a result, utilization can be maintained at much higher levels without sacrificing flexibility.
Both storage-area networks (SAN) and network-attached storage (NAS) allow much more efficient management of resources than storage that is directly attached to each server (DAS). With SAN or NAS, average utilization can be increased to 85%. Combined with the flexibility offered by comprehensive storage management products, SAN and NAS can dramatically reduce the total cost of ownership (TCO) from over $10 per gigabyte to under $5 per gigabyte.
SAN and NAS storage, combined with virtualization and management software, offer several benefits:
* Much increased utilization of storage resources through increased allocation efficiency.
* Lower operating costs through centralized management.
* Increased flexibility during periods of expansion through improved scalability.
If you are discovering very low levels of utilization in your storage resources, especially if they consist primarily of direct-attached storage (DAS), you may find many benefits in a comprehensive storage strategy incorporating SAN, NAS and management software.
To maximize the benefits of such a strategy you must examine your storage costs from a TCO perspective – operating costs are just as significant as the initial capital expenses. Virtualization, centralized management and consolidation will allow you to reduce your operating costs substantially while increasing your utilization. Finally, don’t forget the hidden benefit: A flexible and rapidly scalable storage infrastructure will allow you to deploy new applications, increasing your business agility.
