Adaptec MAN-00005-UG, Installation And User Manual

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Glossary
A
Active/Active
A synonym for Dual Active controllers. Under normal
operating conditions, both controllers in a dual active
controller configuration are actively processing I/O.
Active/Passive
A synonym for Hot Standby.
Active Termination
A type of terminator used in current SCSI channel setups,
which utilizes an active Voltage regulator, thus closely
matching cable impedance.
ANSI
American National Standards Institute, a standards
organization that promotes and facilitates understanding
among qualified members for the implementation of
agreed upon code and signaling standards and conformity.
ANSI represents the U.S. in the ISO (International
Standards Organization).
Applet
Small application programs that are usually built into an
operating system or a larger application program and
designed to run from within another application. The built-
in writing and drawing programs that come with Windows
are sometimes called “applets.” Applications that run in a
web browser are often Java-based applets.
Application Program
A program designed to perform a specific function directly
for the user or, in some cases, for another application
program. Examples of applications include word
processors, database programs, Web browsers,
development tools, drawing, paint and image editing
programs, and communication programs.
Application Server
A centralized computer that holds and distributes
application programs to users.
ASIC
Application-Specific Integrated Circuit, a chip created for a
specific application.
Array
Multiple disk drives configured to behave as a single,
independent disk drive. See also Disk Array.
Asynchronous Data Transfer
Data transfer not synchronized to a set timing interval.
Asynchronous devices must wait for a signal from the
receiving device after each byte of data.
Auto Swap
The exchange of a pre-installed replacement unit in a disk
system for a defective one; the disk system performs the
substitution without human intervention while continuing
to carry out its normal functions (compare with Hot Swap).
Automatic Rebuild
The controllers provide automatic rebuild capabilities in
the event of a physical disk drive failure. The controller
performs a rebuild operation automatically when a disk
drive fails and both of the following conditions are true: -
A standby or hot spare disk drive of identical or larger size
is found attached to the same controller; - • All system
drives that are dependent on the failed disk drive are
configured as a redundant array: RAID 1, RAID 3, RAID
5, or RAID 0+1. During the automatic rebuild process,
system activity continues; however, system performance
may degrade slightly.
Automatic Switchover
See Failover
B
Background Initialization
Where the initialization process of a disk array takes place
in the background, allowing use of a disk array within
seconds instead of several hours. Also known as
Immediate RAID Availability.
BBU
Battery Backup Unit, provides a battery backup for data
currently stored in the on-board cache memory during
intermittent power loss to the controller. In the event of a