Digital Equipment StorageWorks UltraSCSI DS-BA370 Series, User Manual

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Glossary
UltraSCSI RAID Enclosure Glossary–11
power verification and addressing assembly
See PVA.
PVA
Power Verification and Addressing assembly. The module whose primary
functions are (1) allow the user to select the enclosure UltraSCSI bus ID,
(2) enable the user to place the subsystem in a standby power mode and
return it to an operational status. (3) in conjunction with the associated
EMU ensures that critical power functions are monitored.
qualified device
See supported device.
quiesce
To make a bus inactive or dormant. For example, you must quiesce SCSI
bus operations when warm swapping an SBB.
quiescent
A bus that is inactive, still, or dormant.
radio frequency interference
See RFI.
RAID
Redundant array of independent disks. A set of storage techniques devised
to increase the performance and availability of a storage subsystem.
redundant power supply configuration
A capability of StorageWorks cabinet and shelves to ensure there is no
single point of power failure. (1) For a cabinet two ac power sources and
two distribution units or power controllers distribute primary and redundant
ac power to shelf power supplies. (2) For a shelf, the primary and redundant
shelf SBB power supplies ensure the dc power is available even when there
is a failure of one supply, one ac source, or one distribution unit or power
controller.
repeater
See bus extender.