IBM TS4500, Введение и руководство по планированию

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tape library, a group of parts that
provides a mounting platform for the
gripper mechanism and the bar code
reader. The pivot assembly can rotate 180°
about the vertical axis.
point load
On a floor, one or more locations where
the weight of an object is concentrated.
point-to-point topology
In communications, the physical or logical
arrangement of nodes in a network to
facilitate data transmission between two
locations without the use of any
intermediate display station or computer.
port (1) A system or network access point for
data entry or exit.
(2) A connector on a device to which
cables for other devices such as display
stations and printers are attached.
(3) The representation of a physical
connection to the link hardware. A port is
sometimes referred to as an adapter;
however, there can be more than one port
on an adapter.
Portable Document Format (PDF)
A standard that is specified by Adobe
Systems, Incorporated, for the electronic
distribution of documents. The PDF files
are compact, can be distributed globally
(via e-mail, the Web, intranets, or
CD-ROM), and can be viewed with the
Acrobat Reader, which is software from
Adobe Systems that can be downloaded
at no cost from the Adobe Systems home
page.
power cord
A cable that connects a device to a source
of electrical power.
power cord plug
On a power cord, the male fitting for
making an electrical connection to a
circuit by insertion into a receptacle.
power distribution unit (PDU)
A unit that provides ac distribution
within a TS4500 tape library frame by
supplying multiple internal ac outlets
from a single external ac power cord.
power off, powered off
(1) To remove electrical power from a
device.
(2) The state of a device when power has
been removed from it.
power on, powered on
(1) To apply electrical power to a device.
(2) The state of a device when power is
applied to it.
power-on indicator
Above the power button, a green light
that, when lit, indicates that dc power is
available within the TS4500 tape library.
power receptacle
The mounted female electrical fitting that
contains the live parts of the circuit.
power supply
The electrical component of a computer
system that converts standard ac current
to the lower voltage dc current used by
the computer. The amount of current a
power supply can provide is rated in
amperes.
power switch
See library power switch .
prestage
The movement of a cartridge from an HD
slot to a cartridge cache. See also destage .
protocol
The meanings of, and the sequencing
rules for, requests and responses that are
used for managing a network,
transferring data, and synchronizing the
states of network components.
put Pertaining to the TS4500 tape library, to
place, by means of a robotic device, a tape
cartridge into a storage slot, drive, or I/O
station.
Q
quiesce
To put a device into a temporarily
inactive or inhibited state, but not remove
it from the system.
R
RABF See recursive accumulating backhitchless
flush .
radio frequency identification labels
An adhesive bar code label with an
embedded radio frequency identification
tag that can be used to track tape
cartridges.
Glossary
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