IBM TotalStorage FAStT600, Инструкция по установке и эксплуатации

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bridge. A SAN device that provides physical and
transport conversion, such as fibre channel to SCSI
bridge.
bridge group. A bridge and the collection of devices
connected to it. Bridge Groups are discovered by the
SANavigator tool and displayed with a gray background
on the Physical and Data Path Maps.
broadcast. A method of sending an SNMP request for
information to all the devices on a subnet that use a
single special request. Because of its efficiency, the
SANavigator tool sets its default method of discovery to
broadcast. However, a network administrator might
disable this method on the network router.
cathode ray tube (CRT). An electrical device for
displaying images by exciting phosphor dots with a
scanned electron beam. CRTs are found in computer
VDUs and monitors, televisions, and oscilloscopes.
CDPD. See cellular digital packet data .
cellular digital packet data (CDPD). A wireless
standard that provides two-way, 19.2 kps packet data
transmission over existing cellular telephone channels.
CGA. See color graphics adapter .
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.
color graphics adapter (CGA). An early, now
obsolete, IBM video display standard for use on IBM
PCs. CGA displays 80 x 25 or 40 x 25 text in 16 colors,
640 x 200 pixel graphics in two colors or 320 x 200
pixel graphics in four colors.
command. Any selection on a dialog box or elsewhere
in the user interface that causes the SANavigator tool to
perform a task.
community strings. The name of a community
contained in each SNMP message. SNMP has no
standard mechanisms for verifying that a message was
sent by a member of the community, keeping the
contents of a message private, or for determining if a
message has been changed or replayed.
CRC. See cyclic redundancy check .
CRT. See cathode ray tube .
cyclic redundancy check (CRC). (1) 1) A redundancy
check in which the check key is generated by a cyclic
algorithm. (2) 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 .
device type. Identifier used to place devices in the
physical map, such as the switch, hub, storage.
direct access storage device (DASD). IBM
mainframe terminology for a data storage device by
which information can be accessed directly, instead of
by-passing sequentially through all storage areas. For
example, a disk drive is a DASD, in contrast with a tape
drive, which stores data as a linear sequence.
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 controller .
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 N_Port
Identifier for the FC device. It is not used in the
FC-SCSI hardware path ID. It is required to be the
same for all SCSI targets logically connected to an FC
adapter.
DRAM. See dynamic random access memory .
dynamic random access memory (DRAM). A
storage in which the cells require repetitive application
of control signals to retain stored data.
E_Port. An expansion port that connects the switches
for two fabrics (also used for McData ES-1000 B ports).
ECC. See error correction coding .
EEPROM. See Electrically Erasable Programmable
Read-Only Memory .
EGA. See enhanced graphics adapter .
electrically eErasable programmable read-only
memory (EEPROM).
A type of non-volatile storage
device that can be erased with an electrical signal.
Writing to EEPROM takes much longer than reading. It
also can only be reprogrammed a limited number of
times before it wears out. Therefore, it is appropriate for
storing small amounts of data that are changed
infrequently.
electrostatic discharge (ESD). The flow of current
that results when objects that have a static charge
come into close enough proximity to discharge.
enhanced graphics adapter (EGA). An IBM video
display standard that provides text and graphics with a
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IBM TotalStorage FAStT600 Fibre Channel Storage Server: Installation and User’s Guide