HP zx2000 Start Here Manual page 32

increases. Disk 'a' is the master on IDE channel 0, and 'b' is the
slave on that channel. Disk 'c' is the master on IDE channel 1,
and 'd' is the slave on that channel. IDE disks are not necessarily
consecutive (e.g. if you do not have a slave device on channel 0,
disk w/ ID hdb is simply skipped).
SCSI disks are named /dev/sd<n> where 'n' is 'a' to 'z', then
'aa' to 'az', etc. Disks are ordered first by controller, then by
number on the bus. Disk 'a' is the lowest SCSI ID on the first
controller, 'b' is the next lowest, etc.
As each driver is initialized, it registers all the disks on the
controllers it supports. When a disk is registered, it is assigned
the next drive name in order. A single driver may support
multiple controllers, and the order in which it discovers
controllers is driver-dependent. For example, the sym53c8xx
driver in stock Linux kernels looks for all 875 controllers, then
all 896 controllers, then all 1010 controllers.
Similarly, if you have two controllers with two disks each
supported by the sym53c8xx driver, and one controller with three
disks supported by the mptscsih driver, disk naming will depend
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