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Device backup options – HP B6960-90078 User Manual

Page 279

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Backup

Using Backup Options

Chapter 5

249

Device Backup Options

You can select the options listed below for each backup device in use.
None of the settings are needed, because

CRC Check

,

Concurrency

, and

Media Pool

use the default values that are set when the device is

configured. The

Prealloc List

value is specified along with the media

pool settings.

CRC Check

Set this option to have Data Protector calculate the CRC (Cyclic
Redundancy Check) when a backup runs. CRC is an enhanced

checksum

function that lets you later confirm using the

Verify

option whether or

not data has been written correctly to the medium.

The default value is

OFF

.

Concurrency

Concurrency allows more than one Disk Agent to write to one backup
device. Data Protector can then keep the devices streaming if data can be
accepted faster than a Disk Agent can send it. The maximum
concurrency value is 32.

Data Protector provides default values for all supported devices.

Media Pool

This option selects the media pool with the media you will use for a
backup. If not defined, a default pool, which is a part of device
specification, is used.

Prealloc List

The Prealloc List is a subset of media in the media pool used for a
backup. It specifies the order in which the media will be used. When
using the Prealloc List and the

Strict

media allocation policy with the

backup device, Data Protector expects the sequence of the media in the
device to correspond with that specified in the Prealloc List. If the
media are not available in this sequence, Data Protector issues a mount
request. If no media are specified in this list, then the Data Protector
allocation procedure is used to allocate media.