HP StorageWorks HSG80 Array Controller V8.7 Maintenance And Service Manual page 179

Glossary
transfer data rate
The speed at which data may be exchanged with the central processor, expressed in thousands
of bytes per second.
Ultra SCSI bus
A Fast-20 SCSI bus.
uninterruptible power supply
See UPS
unit
A container made accessible to a host. A unit may be created from a single disk drive. A unit
may also be created from a more complex container such as a RAIDset. The controller
supports a maximum of eight units on each target. See also target and target ID number.
UPS
Uninterruptible power supply. A battery-powered power supply guaranteed to provide power
to an electrical device in the event of an unexpected interruption to the primary power supply.
Uninterruptible power supplies are usually rated by the amount of voltage supplied and the
length of time the voltage is supplied.
VHDCI
Very High-Density-Cable Interface. A 68-pin interface that is required for Ultra SCSI connections.
virtual terminal
A software path from an operator terminal on the host to the controller CLI interface,
sometimes called a host console. The path can be established via the host port on the controller
or via the maintenance port through an intermediary host. See also maintenance terminal.
warm swap
A device remove/replace procedure using hot-pluggable method.
write-back cache
See cache module
write-back caching
A cache management method used to decrease the subsystem's response time to write requests
by allowing the controller to declare the write operation "complete" as soon as the data reaches
its cache memory. The controller performs the slower operation of writing the data to the disk
drives at a later time.
HSG80 Array Controller V8.7 Maintenance and Service Guide Glossary–13