Logical Unit Numbers (LUN)
It is possible to have a single SCSI ID support more than one device. Logical unit numbers (LUNs) can be used to provide a unique identifier for up to seven subunits per ID number. These are used primarily in hard disk drive arrays to create one large logical drive out of several smaller physical drives. LUNs require highly specialized software and are most often found in network servers running NetWare, Windows NT, or UNIX.