IBM Advanced SerialRAID Adapters SA33-3285-02, User Manual

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Glossary
This glossary explains terms and abbreviations
that are used in the manual. The glossary
contains terms and definitions from the IBM
Dictionary of Computing.
If you do not find the term or abbreviation for
which you are looking, try the index or refer to the
IBM Dictionary of Computing at URL:
http://www.networking.ibm.com/nsg/nsgmain.htm
A
array. Two or more disk drives that are
interconnected to increase security, performance,
or reliability.
attribute. A named property of an entity; for
example, the attributes of a RAID array include
state, current use, and size of array.
B
boot. To prepare a computer system for
operation by loading an operating system.
buffer. A routine or storage that is used to
compensate for a difference in rate of flow of data,
or time of occurrence of events, when transferring
data from one device to the other.
C
candidate disk. Disk drives that are available for
use in an array.
component. The components of a RAID array
are the member disk drives that are configured for
that array. The component of a fast-write hdisk is
the array or disk drive that is configured for
fast-write operations.
contiguous. Touching or joining at a common
edge or boundary; for example, an unbroken
consecutive series of storage locations.
couple. To attach a copy array to a RAID-1 or
RAID-10 array, and copy data from the RAID-1 or
RAID-10 array to that copy array. The metadata of
the copy array is updated to indicate that it is part
of the parent RAID array. The metadata of the
parent array is updated to show that the copy
array is to be used as a third copy. The copy array
is made offline, and is no longer accessible.
D
daemon. In the operating system, a program that
runs unattended to perform a standard service.
Some daemons are triggered automatically to
perform their task; others operate periodically.
Synonymous with demon.
deconfigure. To remove a disk drive from being
a member of an array.
Degraded state. The state that a RAID array
enters if, while in the Exposed state, it receives a
write command. See also Exposed state.
descriptor. In the object data manager (ODM), a
named and typed variable that defines one
characteristic of an object.
device driver. (1) A file that contains the code
needed to use an attached device. (2) A program
that enables a computer to communicate with a
specific peripheral device. (3) A collection of
subroutines that control the interface between I/O
device adapters and the processor.
domain. That part of a computer network in
which the data processing resources are under
common control.
DMA. Direct memory access.
E
EEPROM. Electrically erasable read-only
memory.
enclosure. A device or unit that contains disk
drives. A disk subsystem (for example, a 7133).
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