Network-attached storage (NAS) is a type of file computer storage device that provides a local-area network with file-based shared storage. This typically comes in the form of a manufactured computer appliance specialized for this purpose, containing one or more storage devices.
Network attached storage devices are used to remove the responsibility of file serving from other servers on a network, and allows for a convenient way to share files among multiple computers. Benefits of dedicated network attached storage include faster data access, easier administration, and simple configuration.
In an enterprise, a network attached storage array can be used as primary storage for storing unstructured data, and as backup for archiving or disaster recovery. It can also function as an email, media database or print server for a small business. Higher end network attached storage devices can hold enough disks to support RAID, a storage technology that allows multiple hard disks into one unit to provide better performance times, redundancy, and high availability.
Data on NAS systems is often mirrored (replicated) to another NAS system, and backups or snapshots of the footprint are kept on the NAS for weeks or months. This leads to at least three or more copies of the data being kept on expensive NAS storage.