IBM 7133 D40, Operator'S Manual

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Location Code Format for 7133 systems
See “Location Codes” in the operator guide for your system for general information
about location codes.
Pdisks, Hdisks, and Disk Drive Module Identification
The physical disk drives (pdisks) in an SSA subsystem can be configured as logical
units (LUNs). A LUN is also known as an hdisk, and can consist of one or more
physical disk drives. An hdisk in an SSA subsystem might, therefore, consist of one
pdisk or several pdisks.
The configuration software also allocates an identification (hdisk and pdisk number) to
each disk drive module during the configuration of the SSA loop. The disk drive
modules do not have fixed physical addresses.
The numeric identifiers of pdisks, hdisks, and the disk drive module slots of a 7133 are
not related to each other. For example, pdisk1 is not necessarily installed in slot 1 of
the 7133.
The system software recognizes the disk drive module by a machine-readable number
that is written on the electronics card of the disk drive module. This number is shown
also on the label at the front of a disk drive module. The service aids show the number
as the last eight digits of the IEEE 16-digit SSA unique identifier (UID).
Service actions are always related to physical disk drives. For this reason, errors that
occur on SSA disk drives are always logged against the physical disk drive (pdisk).
A B C D E F I G J H - - -
Expansion adapter position
System I/0 Bus identifier
Disk drive module number
1 through 16 (decimal)
Enclosure ID
(the four characters that appear in
the display at the front of the 7133 unit)
Expansion drawer
Adapter position
(number of the slot, 1 through 8,
containing the SSA adapter)
72
7133 Models D40 and T40 Operator Guide