HP B6960-96035, Руководство по концепциям

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Result Condition
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.
Failover of the
application during
backup activity without
Cell Manager failover
(Cell Manager runs on
other node than the
application).
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
Incremental backup Full backup
Backs up only changes made since
a previous backup, which requires
less time and media space. Takes more time to complete than
incremental backup and requires
more media space. Resources
It is less likely that the backup will
require additional media. 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. Device handling
Concepts guide 91