Hitachi CBL, Hardware Service Manual

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Glossary–8
Hitachi Unified Storage Hardware Service Guide
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A B C D E F G H I
J K
L M
N O
P
Q
R S T U V W
X Y
Z
L
LAN
Local-area network. A computer network that spans a relatively small
area, such as a single building or group of buildings.
Load
In UNIX computing, the system load is a measure of the amount of
work that a computer system is doing.
Logical
Describes a user's view of the way data or systems are organized. The
opposite of logical is physical, which refers to the real organization of a
system. A logical description of a file is that it is a quantity of data
collected together in one place. The file appears this way to users.
Physically, the elements of the file could live in segments across a disk.
M
Microcode
The lowest-level instructions directly controlling a microprocessor.
Microcode is generally hardwired and cannot be modified. It is also
referred to as firmware embedded in a storage subsystem.
Microsoft Cluster Server
Microsoft Cluster Server is a clustering technology that supports
clustering of two NT servers to provide a single fault-tolerant server.
P
Pair
Refers to two volumes that are associated with each other for data
management purposes (for example, replication, migration). A pair is
usually composed of a primary or source volume and a secondary or
target volume as defined by you.
Pair status
Internal status assigned to a volume pair before or after pair
operations. Pair status transitions occur when pair operations are
performed or as a result of failures. Pair statuses are used to monitor
copy operations and detect system failures.
Parity
The technique of checking whether data has been lost or corrupted
when it's transferred from one place to another, such as between
storage units or between computers. It is an error detection scheme