the backed up data, and increase the data availability and

 

accessibility for restore. The backup stages consist of backing

 

up data to one media type first (for example disk) and later

 

copying it to a different media type (for example tape).

distributed file

A media format, available with the file library, which supports

media format

a space efficient type of synthetic backup called virtual full

 

backup. Using this format is a prerequisite for virtual full backup.

 

See also virtual full backup.

Distributed File

A service that connects file shares into a single namespace. The

System (DFS)

file shares can reside on the same or on different computers.

 

DFS provides client access to the resources in a

 

location-transparent manner.

DMZ

The Demilitarized Zone (DMZ) is a network inserted as a "neutral

 

zone" between a company's private network (intranet) and the

 

outside public network (Internet). It prevents outside users from

 

getting direct access to company servers in the intranet.

DNS server

In the DNS client-server model, this is the server containing

 

information about a portion of the DNS database that makes

 

computer names available to client resolvers querying for name

 

resolution across the Internet.

domain controller

A server in a network that is responsible for user security and

 

verifying passwords within a group of other servers.

DR image

Data required for temporary disaster recovery operating system

 

(DR OS) installation and configuration.

DR OS

A disaster recovery operating system is an operating system

 

environment in which disaster recovery runs. It provides Data

 

Protector a basic runtime environment (disk, network, tape, and

 

filesystem access). The OS has to be installed and configured

 

before the Data Protector disaster recovery can be performed.

 

DR OS not only hosts the Data Protector disaster recovery

 

process but is also a part of the restored system because it

 

replaces its own configuration data with the original

 

configuration data.

drive

A physical unit that receives data from a computer system and

 

can write it onto a magnetic medium (typically a tape drive). It

360Glossary