IBM DS4700 EXPRESS, Installation, User'S, And Maintenance Manual

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auto-volume transfer/auto-disk transfer (AVT/ADT).
A function that provides automatic failover in case of
controller failure on a storage subsystem.
AVT/ADT. See auto-volume transfer/auto-disk transfer .
AWT. See Abstract Windowing Toolkit .
basic input/output system (BIOS). The personal
computer code that controls basic hardware operations,
such as interactions with diskette drives, hard disk
drives, and the keyboard.
BIOS. See basic input/output system .
BOOTP. See bootstrap protocol .
bootstrap protocol (BOOTP). In Transmission Control
Protocol/Internet Protocol (TCP/IP) networking, an
alternative protocol by which a diskless machine can
obtain its Internet Protocol (IP) address and such
configuration information as IP addresses of various
servers from a BOOTP server.
bridge. A storage area network (SAN) device that
provides physical and transport conversion, such as
fibre channel to small computer system interface (SCSI)
bridge.
bridge group. A bridge and the collection of devices
connected to it.
broadcast. The simultaneous transmission of data to
more than one destination.
cathode ray tube (CRT). A display device in which
controlled electron beams are used to display
alphanumeric or graphical data on an
electroluminescent screen.
client. A computer system or process that requests a
service of another computer system or process that is
typically referred to as a server. Multiple clients can
share access to a common server.
command. A statement used to initiate an action or
start a service. A command consists of the command
name abbreviation, and its parameters and flags if
applicable. A command can be issued by typing it on a
command line or selecting it from a menu.
community string. The name of a community
contained in each Simple Network Management
Protocol (SNMP) message.
concurrent download. A method of downloading and
installing firmware that does not require the user to stop
I/O to the controllers during the process.
CRC. See cyclic redundancy check .
CRT. See cathode ray tube .
CRU. See customer replaceable unit .
customer replaceable unit (CRU). An assembly or
part that a customer can replace in its entirety when any
of its components fail. Contrast with
field replaceable
unit (FRU) .
cyclic redundancy check (CRC). (1) A redundancy
check in which the check key is generated by a cyclic
algorithm. (2) An error detection technique performed at
both the sending and receiving stations.
dac. See disk array controller .
dar. See disk array router .
DASD. See direct access storage device .
data striping. See striping .
default host group. A logical collection of discovered
host ports, defined host computers, and defined host
groups in the storage-partition topology that fulfill the
following requirements:
v Are not involved in specific logical drive-to-LUN
mappings
v
Share access to logical drives with default logical
drive-to-LUN mappings
device type. Identifier used to place devices in the
physical map, such as the switch, hub, or storage.
DHCP. See Dynamic Host Configuration Protocol .
direct access storage device (DASD). A device in
which access time is effectively independent of the
location of the data. Information is entered and retrieved
without reference to previously accessed data. (For
example, a disk drive is a DASD, in contrast with a tape
drive, which stores data as a linear sequence.) DASDs
include both fixed and removable storage devices.
direct memory access (DMA). The transfer of data
between memory and an input/output (I/O) device
without processor intervention.
disk array controller (dac). A disk array controller
device that represents the two controllers of an array.
See also
disk array router .
disk array router (dar). A disk array router that
represents an entire array, including current and
deferred paths to all logical unit numbers (LUNs) (hdisks
on AIX). See also
disk array controller .
DMA. See direct memory access .
domain. The most significant byte in the node port
(N_port) identifier for the fibre-channel (FC) device. It is
not used in the fibre channel-small computer system
interface (FC-SCSI) hardware path ID. It is required to
be the same for all SCSI targets logically connected to
an FC adapter.
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IBM System Storage DS4700 Express Storage Subsystem: Installation, User’s and Maintenance Guide