IBM Enterprise Storage Server 2105 E10, Introduction And Planning Manual

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organizationally unique identifier (OUI). An identifier
that identifies an organization according to IEEE
standards.
original equipment manufacturer’s information
(OEMI). A reference to an IBM guideline for a
computer peripheral interface. More specifically, refer to
IBM System/360 and System/370 I/O Interface Channel
to Control Unit Original Equipment Manufactures’
Information. The interface uses ESA/390 logical
protocols over an I/O interface that configures attached
units in a multi-drop bus topology.
OUI. See organizationally unique identifier.
P
parallel access volume (PAV). Created by
associating multiple devices of a single control-unit
image with a single logical device. Up to 8 device
addresses can be assigned to a parallel access volume.
parity. A data checking scheme used in a computer
system to ensure the integrity of the data. The RAID
implementation uses parity to recreate data if a disk
drive fails.
path group. The ESA/390 term for a set of channel
paths that are defined to a controller as being
associated with a single LPAR. The channel paths are
in a group state and are online to the host.
path-group identifier. The ESA/390 term for the
identifier that uniquely identifies a given LPAR. The
path-group identifier is used in communication between
the LPAR program and a device. The identifier
associates the path-group with one or more channel
paths, thereby defining these paths to the control-unit
as being associated with the same LPAR.
PAV. See
parallel access volume.
PCI. See
program-controlled interruption.
PE. See
IBM product engineering.
Peer-to-Peer Remote Copy (PPRC). A function of a
storage controller that maintains a consistent copy of a
logical volume on the same controller or on another
controller. You access the controllers over an ESCON
I/O interface. All modifications that any attached host
performs on the primary logical volume are also
performed on the secondary logical volume.
peripheral component interconnection. see
program-conrolled interruption.
point-to-point connection. A fibre-channel topology
that allows you to interconnect ports directly.
POST. See power-on self test.
power-on self test (POST). A diagnostic test run by
servers or computers when they are turned on.
PPRC. See
Peer-to-Peer Remote Copy.
predictable write. A write operation that can cache
without knowledge of the existing format on the
medium. All writes on FBA DASD devices are
predictable. On CKD DASD devices, a write is
predictable if it does a format write for the first data
record on the track.
product engineering. See
IBM product engineering.
program. A generic term for the software that controls
the operation of a host computer. Typically, the program
is an operating system that allows sharing of the host
resources between multiple tasks.
program-controlled interruption (PCI). An
interruption that occurs when an I/O channel fetches a
channel command word with the program-controlled
interruption flag on. PCI is also called peripheral
component interconnection.
program temporary fix (PTF). A temporary solution or
bypass of a problem diagnosed by IBM in a current
unaltered release of a program
promote. The action of adding a logical data unit to
cache memory.
PTF. See program temporary fix.
R
R0. See track-descriptor record.
rack. See enclosure.
RAID. See
redundant array of independent disks and
array.
random access. A mode of accessing data on a
medium in a manner that requires the storage device to
access nonconsecutive storage locations on the
medium.
rank. See array.
redundant array of independent disks (RAID). A
collection of disk drives that operate independently. The
IBM Enterprise Storage Server protects all storage with
redundant arrays of independent disks (RAID). The ESS
attaches serial storage architecture (SSA) disk drive
modules (DDMs) in RAID-5 configurations. The
implementation of RAID-5 configurations distributes
(stripes) parity across all DDMs in the array. Also see
array.
remote technical assistance information network
(RETAIN). Initial Service Tracking for IBM service
support.
Glossary
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