Hitachi F1500, Руководство по оборудованию

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local area network (LAN)
A computer network that spans a relatively small geographic area, such
as a single building or group of buildings.
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 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
A clustering technology that supports clustering of two NT servers to
provide a single fault-tolerant server.
P
pair
Two logical volumes in a replication relationship in which one volume
contains original data to be copied and the other volume contains the
copy of the original data. The copy operations can be synchronous or
asynchronous, and the pair volumes can be located in the same storage
system (in-system replication) or in different storage systems (remote
replication).
pair status
Indicates the condition of a copy pair. A pair must have a specific status
for specific operations. When a pair operation completes, the status of the
pair changes to a different status determined by the type of operation.
parity
In computers, parity refers to a technique of checking whether data has
been lost or written over when it is moved from one place in storage to
another or when transmitted between computers.
Parity computations are used in RAID drive arrays for fault tolerance by
calculating the data in two drives and storing the results on a third. The
200 Glossary
Hitachi Virtual Storage Platform G1000, G1500, and Virtual Storage Platform F1500 Hardware Guide