Technical data

Glossary–16 HSG80 ACS Solution Software Version 8.6 for Compaq Tru64 UNIX Installation and Configuration
Guide
replacement policy The policy specified by a switch with the SET FAILEDSET command
indicating whether a failed disk from a mirrorset or RAIDset is to be
automatically replaced with a disk from the spareset. The two switch choices
are AUTOSPARE and NOAUTOSPARE.
SBB StorageWorks building block. (1) A modular carrier plus the interface required
to mount the carrier into a standard StorageWorks shelf. (2) any device
conforming to shelf mechanical and electrical standards installed in a 3.5-inch
or 5.25-inch carrier, whether it is a storage device or power supply.
SCSI Small computer system interface. (1) An ANSI interface standard defining the
physical and electrical parameters of a parallel I/O bus used to connect
initiators to devices. (2) a processor-independent standard protocol for
system-level interfacing between a computer and intelligent devices including
hard drives, floppy disks, CD-ROMs, printers, scanners, and others.
SCSI-A cable A 50-conductor (25 twisted-pair) cable generally used for single-ended,
SCSI-bus connections.
SCSI bus signal
converter
Sometimes referred to as an adapter. (1) A device used to interface between
the subsystem and a peripheral device unable to be mounted directly into the
SBB shelf of the subsystem. (2) a device used to connect a differential SCSI
bus to a single-ended SCSI bus. (3) A device used to extend the length of a
differential or single-ended SCSI bus. See also DWZZA, DWZZB, DWZZC,
and I/O module.
SCSI device (1) A host computer adapter, a peripheral controller, or an intelligent
peripheral that can be attached to the SCSI bus. (2) Any physical unit that can
communicate on a SCSI bus.
SCSI device ID
number
A bit-significant representation of the SCSI address referring to one of the
signal lines, numbered 0 through 7 for an 8-bit bus, or 0 through 15 for a
16-bit bus. See also target ID number.
SCSI ID number The representation of the SCSI address that refers to one of the signal lines
numbered 0 through 15.
SCSI-P cable A 68-conductor (34 twisted-pair) cable generally used for differential bus
connections.
SCSI port (1) Software: The channel controlling communications to and from a specific
SCSI bus in the system. (2) Hardware: The name of the logical socket at the
back of the system unit to which a SCSI device is connected.