HP B6960-96035, Руководство по концепциям

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Media condition
The condition of the media also influences which media are selected for backup, for
example, media in good condition are used for backup before media in fair condition.
For more information, see “
Calculating media condition ” on page 150.
Adding data to media during backup sessions
To maximize space usage of media as well as backup and restore efficiency, you
can select how Data Protector treats the space on the medium left over from the
previous backup. This is defined with a media usage policy.
Media usage policy
The available media usage policies are listed below:
Appendable A backup session starts writing data to the space
remaining on the last medium used from a
previous backup session. Subsequent media
needed in this session are written from the
beginning of the tape, hence only unprotected or
new tapes can be used. Appending media
conserves media space but can add complexity
to vaulting, because one medium can contain data
from several media sets.
Non Appendable A backup session starts writing data at the
beginning of the first available medium for
backup. Each medium contains data from a single
session only. This simplifies vaulting.
Appendable of Incrementals
Only A backup session appends to a medium only if
an incremental backup is performed. This allows
you to have a complete set of full and incremental
backups on the same medium, if there is enough
space.
Distributing objects over media
The following figures show some examples of how objects can be distributed over
media:
Media management and devices 148