scsi channel, lun and host ID

a SCSI channel( bus) 最多可接15個drives(不包括RAID controller)
So a channel can have 15個ID

SCSI-based subsystem: 8個drives在一個drive channel上，
SATA-based subsystem:一個drive channel，一個drive



host ID is link cabinet, and the drawers are like LUNs(Logical Unit Number)
一個host ID可以有32個LUN。

Connection between RAID controllers & drives


physical location of physical drives


Mapping partitions to host ID/ LUN