HP B6960-96035 manual Full and incremental backups, Comparison of full and incremental backup

Condition

Failover of the application during backup activity without Cell Manager failover (Cell Manager runs on other node than the application).

Result

Filesystem/disk image backup The backup session fails at failover of the node where the filesystem is installed. The completed objects from the session can be used for restore, the failed (running and pending) objects need to be backed up again by restarting the session manually.

Application backup The backup session fails. The session needs to be restarted manually.

IMPORTANT:

If a failover during backup activity occurs in such a configuration, the MA may not be able to properly abort the session. This results in the corruption of the medium.

Additionally, the Data Protector cluster Cell Manager/client can be integrated with the EMC Symmetrix or HP StorageWorks Disk Array XP environment, producing a very highly-available backup environment. For more information, see the HP Data Protector zero downtime backup administrator's guide.

Full and incremental backups

Data Protector provides two basic types of filesystem backups: full and incremental.

A full backup saves all the files selected for backup in a filesystem. An incremental backup saves only those files that have changed since the last full or incremental backup. This section gives hints on how to choose the backup type and how this influences your backup strategy.

Table 6 Comparison of full and incremental backup

Full backup

Resources Takes more time to complete than incremental backup and requires more media space.

Incremental backup

Backs up only changes made since a previous backup, which requires less time and media space.

Device handling If you use a standalone device with a single drive, you need to change the media manually if a backup does not fit on a single medium.

It is less likely that the backup will require additional media.

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