IBM DCS3700 Installation, User'S, And Maintenance Manual Download

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premium feature key.

A file that the storage

subsystem controller uses to enable an authorized
premium feature. The file contains the feature enable
identifier of the storage subsystem for which the
premium feature is authorized, and data about the
premium feature. See also

feature enable identifier

private loop.

A freestanding arbitrated loop with no

fabric attachment. See also

arbitrated loop

program temporary fix (PTF).

A temporary solution

or bypass of a problem diagnosed by IBM in a current
unaltered release of the program.

PTF.

See

program temporary fix

RAID.

See

redundant array of independent disks (RAID)

RAID level.

An array's RAID level is a number that

refers to the method used to achieve redundancy and
fault tolerance in the array. See also

array, redundant

array of independent disks (RAID)

RAID set.

See

array

RAM.

See

random-access memory

random-access memory (RAM).

A temporary storage

location in which the central processing unit (CPU)
stores and executes its processes. Contrast with

DASD

RDAC.

See

redundant disk array controller

read-only memory (ROM).

Memory in which stored

data cannot be changed by the user except under
special conditions.

recoverable virtual shared disk (RVSD).

A virtual

shared disk on a server node configured to provide
continuous access to data and file systems in a cluster.

redundant array of independent disks (RAID).

collection of disk drives (

array

) that appears as a single

volume to the server, which is fault tolerant through an
assigned method of data striping, mirroring, or parity
checking. Each array is assigned a RAID level, which is
a specific number that refers to the method used to
achieve redundancy and fault tolerance. See also

array,

parity check, mirroring, RAID level, striping

redundant disk array controller (RDAC).

(1) In

hardware, a redundant set of controllers (either
active/passive or active/active). (2) In software, a layer
that manages the input/output (I/O) through the
active controller during normal operation and
transparently reroutes I/Os to the other controller in
the redundant set if a controller or I/O path fails.

remote mirroring.

Online, real-time replication of data

between storage subsystems that are maintained on
separate media. The Enhanced Remote Mirror Option is
a DS5000 premium feature that provides support for
remote mirroring. See also

Global Mirroring

Metro

Mirroring

ROM.

See

read-only memory

router.

A computer that determines the path of

network traffic flow. The path selection is made from
several paths based on information obtained from
specific protocols, algorithms that attempt to identify
the shortest or best path, and other criteria such as
metrics or protocol-specific destination addresses.

RVSD.

See

recoverable virtual shared disk

SAI.

See

Storage Array Identifier

SA Identifier.

See

Storage Array Identifier

SAN.

See

storage area network

SATA.

See

serial ATA

scope.

Defines a group of controllers by their Internet

Protocol (IP) addresses. A scope must be created and
defined so that dynamic IP addresses can be assigned
to controllers on the network.

SCSI.

See

small computer system interface

segmented loop port (SL_port).

A port that allows

division of a fibre-channel private loop into multiple
segments. Each segment can pass frames around as an
independent loop and can connect through the fabric to
other segments of the same loop.

sense data.

(1) Data sent with a negative response,

indicating the reason for the response. (2) Data
describing an I/O error. Sense data is presented to a
host system in response to a sense request command.

serial ATA.

The standard for a high-speed alternative

to small computer system interface (SCSI) hard drives.
The SATA-1 standard is equivalent in performance to a
10 000 RPM SCSI drive.

serial storage architecture (SSA).

An interface

specification from IBM in which devices are arranged
in a ring topology. SSA, which is compatible with small
computer system interface (SCSI) devices, allows
full-duplex packet multiplexed serial data transfers at
rates of 20 Mbps in each direction.

server.

A functional hardware and software unit that

delivers shared resources to workstation client units on
a computer network.

server/device events.

Events that occur on the server

or a designated device that meet criteria that the user
sets.

SFP.

See

small form-factor pluggable

Simple Network Management Protocol (SNMP).

the Internet suite of protocols, a network management
protocol that is used to monitor routers and attached
networks. SNMP is an application layer protocol.

Glossary

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