Storage Area Network File System (SAN File System)

A SAN file system provides a universal namespace to a customer, enabling data production and distribution with the help of uniform file names from any application or client.

Integrity and data consistency are maintained through a SAN file system's control over distributed locks and lease utilization. A SAN file system provides locks that allow client file access and sharing, as required. To ensure these locks, the maximum time frame required by a metadata server is computed in a lease. To retain the locks, a client must contact the metadata server prior to the lease expiration date. A SAN file system also implements rules and policies for automated file allocation.

Key SAN file system attributes include:

• Direct data access via SAN technology: A SAN file system uses a data access model that allows client systems to directly gain data access from storage systems with the help of a high bandwidth SAN. This is done without an interposing server.
• Global namespace: A SAN file system provides an individual, standard and universal namespace view of all system files to all clients. This is implemented by a system administrator, versus manual configuration by clients.
• File sharing: All clients, regardless of hardware platform or operating system (OS), are given uniform access to stored system data.
• Data management and policy-based storage: A SAN file system is geared toward simplifying storage-resource management and reducing total cost of ownership (TCO). This occurs via the policy-based automated file placement on proper storage devices.