As a data storage device for network users, the disk array needs to provide an interface to the server host or other network devices. This interface is called a host channel or an external host channel. Most external host channels are now Ultra2 SCSI and Ultra3 SCSI, and some products have FC (Fiber Channel Fibre Channel) interfaces due to the connection to the SAN (Storage Area Network).
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Generally, a disk array has a single-host channel disk array and a multi-host channel disk array: a single-host channel disk array can only be connected to one host, and a multi-host channel disk array can be connected to multiple host systems and used at the same time. The flexible expansion capability allows the disk array to be shared in a cluster. Most of the arrays support 73GB, 36GB and 18GB hard drives, and some arrays can support 180GB hard drives and support hot swap. The supported RAID levels are 0, 1 (0+1), 3 and 5. Wait.
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