A Storage Area Network (SAN) is a specialized, high-speed network that provides block-level network access to storage. SANs are typically composed of hosts, switches, storage elements, and storage devices that are interconnected using a variety of technologies, topologies, and protocols.
SAN migration requires strategic thinking, detailed planning, effective preparation and careful execution. The keys to SAN migration success include tasks such as ensuring firmware and driver upgrades are carried out and ensuring you work hand-in-glove with the business to minimize disruption.
If data is sitting on many servers, it is a laborious process for the storage administrator to take it off each server and transfer it to a new home. This might involve steps such as unmounting the file systems using the storage, unplugging the unit, moving it, then connecting it to a different host, and bringing up the file systems on the new machine. In a SAN storage solution, it is a simple matter to move an entire large storage array from one host to another. All you have to do is unmount the file system, quickly reconfigure the SAN then bring up the data on the new host. This saves an enormous amount of time for a storage administrator.
This architecture becomes more and more vital as the size of the amount of storage grows. It is much too cumbersome to attempt to manage multiple TBs of data on a server after server basis. It takes a storage network to do the heavy lifting and remove the drudgery. For instance, if you need to add storage from another array to a server, a SAN-attached architecture enables you to allocate logical unit numbers (LUNs) from multiple arrays to that one server.