HP StorageWorks 4400 Enterprise Virtual Array user ... - BUSINESS IT

asynchronous Events scheduled as the result of a signal requesting the event or that which is
without any specified time relation.
backplane An electronic printed circuit board that distributes data, control, power, and
other signals among components within an enclosure.
bad block A data block that contains a physical defect.
bad block
replacement
A replacement routine that substitutes defect-free disk blocks for those found to
have defects. This process takes place in the controller and is transparent to the
host.
bail lock Part of the power supply AC receptacle that engages the AC power cord
connector to ensure that the cord cannot be accidentally disconnected.
baud The maximum rate of signal state changes per second on a communication circuit.
If each signal state change corresponds to a code bit, then the baud rate and
the bit rate are the same. It is also possible for signal state changes to correspond
to more than one code bit so the baud rate may be lower than the code bit rate.
bay The physical location of a component, such as a drive, I/O module, or power
supply in a drive enclosure. Each bay is numbered to define its location.
bidirectional Also called Bi-Di. The movement of optical signals in opposite directions through
a common fiber cable such as the data flow path typically on a parallel printer
port. A parallel port can provide two-way data flow for disk drives, scanning
devices, FAX operations and even parallel modems.
block Also called a sector. The smallest collection of consecutive bytes addressable on
a disk drive. In integrated storage elements, a block contains 512 bytes of data,
error codes, flags, and the block address header.
cabinet An alternate term used for a rack.
cable assembly A fiber optic cable that has connectors installed on one or both ends. General
use of these cable assemblies includes the interconnection of multimode fiber
optic cable assemblies with either LC or SC type connectors.
When there is a connector on only one end of the cable, the cable assembly
is referred to as a pigtail.
When there is a connector on each end of the cable, the cable assembly is
referred to as a jumper.
CAC Corrective Action Code. An HP Command View EVA graphical user interface
(GUI) display component that defines the action required to correct a problem.
See also read cache,write cache, and mirrored cache.
cache High-speed memory that sets aside data as an intermediate data buffer a host
and the storage media. The purpose of cache is to improve performance.
carrier A drive-enclosure-compatible assembly containing a disk drive or other storage
devices.
client A software program that uses the services of another software program. The HP
Command View EVA client is a standard internet browser.
clone See Virtual Disk Copy.
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Glossary