Storage consolidation, also called storage convergence is a method of centralizing data storage among multiple servers. The objective is to facilitate data backup and archiving for all subscribers in an enterprise, while minimizing the time required to access and store data. Other desirable features include simplification of the storage infrastructure, centralized and efficient management, optimized resource utilization, and low operating cost.
There are three storage consolidation architectures in common use: network-attached storage (NAS), redundant array of independent disks (RAID), and the storage area network (SAN). In NAS, the hard drive that stores the data has its own network address. Files can be stored and retrieved rapidly because they do not compete with other computers for processor resources. In RAID storage consolidation, the data is located on multiple disks. The array appears as a single logical hard drive. This facilitates balanced overlapping of input/output (I/O) operations and provides fault tolerance, minimizing downtime and the risk of catastrophic data loss. The SAN is the most sophisticated architecture, and usually employs Fibre Channel technology. SANs are noted for high throughput and ability to provide centralized storage for numerous subscribers over a large geographic area. SANs support data sharing and data migration among servers.