HP 6400.8400 Enterprise Virtual Array - Manual (Page 137)

B
backplane An electronic printed circuit board that distributes data, control, power, and other signals among
components in 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 The part of the power supply AC receptacle that engages the AC power cord connector to ensure
that the cord cannot be accidentally disconnected.
battery A rechargeable unit mounted within a controller enclosure that supplies backup power to the
cache module in case of primary power shortage.
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 an element, such as a drive, I/O module, EMU 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.
blower See fan.
C
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 P6000 Command View graphical user interface (GUI) display
component that defines the action required to correct a problem.
cache High-speed memory that sets aside data as an intermediate data buffer between a host and the
storage media. The purpose of cache is to improve performance.
cache battery See battery.
carrier A drive enclosure-compatible assembly containing a disk drive or other storage devices.
client An intelligent device that requests services from other intelligent devices. In the context of HP
P6000 Command View, a client is a computer that is used to access the software remotely using
a supported browser.
clone A full copy of a volume usable by an application.
communication
LUN See console LUN.
condition report A three-element code generated by the EMU in the form where e.t. is the element type (a
hexadecimal number), en. is the element number (a decimal number), and ec is the condition
code (a decimal number).
console LUN A SCSI-3 virtual object that makes a controller pair accessible by the host before any virtual disks
are created. Also called a communication LUN.
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