SANs

A storage area network (SAN) is a pool of storage systems that are interconnected to the servers in an enterprise. A SAN administrator is the person responsible for administering the various resources that make up the SAN.

A SAN allows the establishment of direct connections between storage devices and servers. It offers simplified storage management, scalability, flexibility, availability, and improved data access, movement, and backup.

A SAN storage system consists of two or four system nodes that are arranged in a clustered system. Clustered Lenovo Storage V5030 systems can support four nodes. These nodes appear as part of the SAN fabric. The nodes are connected to the host systems, RAID storage systems, and the storage devices to create the SAN. Other devices, such as fabric switches, might be required to complete the SAN.

A systemthat has suitable host interface adapters appears as part of the SAN fabric along with the host systems and any other storage systems, all connected together by fabric switches to create the SAN.

There are two types of SAN: redundant and counterpart. A redundant SAN consists of a fault tolerant arrangement of two counterpart SANs. A redundant SAN configuration provides two independent paths for each device that is attached to the SAN. A counterpart SAN is a non-redundant portion of a redundant SAN and provides all the connectivity of the redundant SAN, but without the redundancy. Each counterpart SAN provides an alternative path for each device that is attached to the SAN.
Note: For best availability, use a redundant SAN with the system. Non-redundant SANs are also supported.