Glossary
1
10Gb Ethernet
A 10 gigabit per second (Gb/s) Ethernet
connection using either fiber-optic cables or
twisted-pair copper wires.
10Gb iSCSI
An iSCSI connection that runs on a 10Gb
Ethernet network.
A
Active Directory
Microsoft Active Directory® is a directory
service that stores directory information on a
network and makes this information available to
network users and administrators. AD stores
information about user accounts, such as
names, passwords, phone numbers, and so on,
and enables other authorized users on the same
network to access this information.
Anti-static wrist-strap
An antistatic device used to prevent electrostatic
discharge (ESD) by safely grounding a person
working on electronic equipment. Also called an
ESD strap or a grounding bracelet.
Asynchronous data replication
Asynchronous data replication allows you to
replicate data between two s —a primary and a
remote (or secondary) system—over a LAN or
WAN connection. The asynchronous data
replication function provides off-site disaster
recovery protection for the . It delivers high-
performance asynchronous replication of your
data over both LAN and WAN networks,
providing protection from site-specific and
regional disasters. The ’s asynchronous data
replication function uses snapshot-based
replication technology: when you initiate data
replication, the asynchronous data replication
function takes a snapshot of the data on the
primary and sends either the entire contents up
to the snapshot to the remote —in the case of an
initial data replication; or, only the changes since
the last replication—in the case of an incremental
update. Because the asynchronous data
replication function takes a snapshot of the
source data (on the primary system), the data
always remains accessible to clients during
replication. Additionally, the asynchronous data
replication function keeps track of data transfers
during replication by checkpointing the data
stream. If data replication is interrupted—due to a
network disconnect issue—the asynchronous
data replication function automatically restarts
replication from the most recent checkpoint. The
asynchronous data replication function includes
features that reduce bandwidth consumption
during data replication, and consequently
minimize the infrastructure cost of data
replication and disaster recovery. Specifically,
the asynchronous data replication function only
replicates the data that changed since the last
replication—which significantly reduces
replication time and bandwidth requirements,
particularly where only small parts of large files
change or where only share metadata has
changed on the primary site.
Automatic replication
In asynchronous replication, an automatic
replication refers to a scheduled replication that
occurs according to a schedule you define. You
can configure a separate replication schedule for
each storage pool on the .
B
Bit
The smallest unit of digital data, representing a 0
or a 1. Abbreviated “b”.
Boot drive
The device from which a computer’s operating
system is loaded. Typically, an internal hard disk
drive (or one of several partitions on such a drive)
is used for this purpose, but any attached
storage device—such as an optical disc drive, a
Glossary
Nexsan Unity Hardware Reference Guide
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