Storage Area Network - is a network of storage devices that are connected to each other and to a server, or cluster of servers, which act as an access point to the SAN. A high availability high-performance dedicated storage network that connects servers & storage in a secure, flexible & scalable architecture.

When using a SAN, the File Server calls for the back-up to tape and disconnects from the disk subsystem. The disk subsystem then moves all of the asked for data directly to the Tape back-up drive/library and when completed notifies the File Server that the job has completed. By adding software we can make a snapshot copy of the data in an open file, that data can then be sent to the Tape back-up device while the users continue to access the open file. This allows for a back-up window of 24 hours per day without impacting the performance of the Server or the LAN.

Apart from offering high availability and high performance for the applications, SAN also offers small backup windows. Since the entire environment runs on fibre channel connectivity, even the tape libraries are connected on the same fibre channel network. Totally LAN free backups happen across high speed fibre channel connectivity.

SAN based backups are not only LAN free but are also referred to as serverless backups. This happens because the data travels directly from the SAN disk system to the tape libraries. There are no backup overheads on the production servers. Dynamic Drive Sharing offered further helps in better backup performance.

The backups on SAN based disk system with fibre connectivity utilizing snapshots are ideal both for local tape library and also for immediate remote location mirroring for disaster recovery purposes.