As a storage device for data, the disk array is used by network users, and the disk array provides the interface, which is connected to the server host or other network device, which we call the host channel or the external host channel. Most external host channels are now ULTRA2 SCSI and ULTRA3 SCSI, and some products have FC (Fiber channel Fibre Channel) interfaces with the SAN (Storage area Network) connection.
Typically, the disk array has a single host channel disk array and a multi-host channel disk array: Single host channel disk array can only be one host, multiple host channel disk array can be connected to multiple host systems, and at the same time, there is a lot of flexibility to expand the ability to cluster (Cluster) way to share the disk array. Most arrays support 73GB, 36GB, and 18GB hard drives, as well as parts of the array that support 180GB hard drives and hot swappable, with 0, 1 (0+1), 3, and 5 RAID levels supported.