NonStop System Glossary

automatic cartridge loader (ACL)
A device that stores multiple cartridge tapes and loads them automatically, one at a time, into a
tape drive.
automatic configuration
The automatic assignment of magnetic disk attributes to an internal disk drive when it is inserted
into a slot. Also known as plug and play.
averaging
A measurement method for determining the average value of alternating voltage and current
waveforms. The averaging method involves sampling a waveform and averaging the samples over
the period of one cycle.
AWAN
See asynchronous wide area network (AWAN) servers.
AXCEL
The command used to invoke the Accelerator on a TNS/R or TNS/E system.
B
back-end board (BEB)
On some tape drives or disk drive modules, a circuit board that translates fiber-optic signals from
a 6760 ServerNet device adapter into small computer system interface (SCSI) commands and
information.
background process
In the Open System Services (OSS) environment, a process that belongs to a background process
group.
background process group
In the Open System Services (OSS) environment, a process group that is both:
• Not a foreground process group.
• A member of a session that has a connection with a controlling terminal
backout
The Distributed Systems Management/Software Configuration Manager (DSM/SCM) action of
making the last configuration applied to the target system inaccessible and replacing it with the
previous configuration.
backplane
A board that has connectors, on one or both sides of the board, into which circuit board assemblies
plug. Backplanes are located behind card cages or disk cages.
BACKUP
A utility for NonStop servers that creates a backup copy of one or more disk files on magnetic
tape. See also RESTORE.
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