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cycle. The same tape rotation enables you to get by with the minimum number of cartridges and not
to be buried in used tapes.
Acronis Backup & Recovery 10 enables you to achieve full automation of tape rotation while backing
up onto tape libraries.
This section provides you with useful information to choose a backup scheme and tape options for
tape rotation.
To calculate the number of tapes required for tape rotation schemes, you can use the method
described in the Tape planning (p. 158) section.
Choosing a backup scheme
When creating a backup policy/plan with a tape library destination, the following backup schemes
are available:
Back up now
,
Back up later
,
Grandfather-Father-Son
,
Tower of Hanoi
, or
Custom
. The
Simple
backup scheme is disabled, because backup consolidation is impossible for archives located
on tapes.
Acronis Backup & Recovery 10 provides automation of tape rotation for
Grandfather-Father-Son
,
Tower of Hanoi
, and
Custom
backup schemes.
Grandfather-Father-Son (p. 35) (GFS) and Tower of Hanoi (p. 38) (ToH) are the most popular backup
schemes to use on tape library devices. These schemes are optimized to maintain the best balance
between a backup archive size, the number of recovery points available from the archive, and the
quantity of required tapes for archiving.
If your backup archive must provide recovery with daily resolution for the last several days, weekly
resolution for the last several weeks and monthly resolution for any time in the past, the most
preferred scheme for you is the
Grandfather-Father-Son
scheme.
If the main goal is to provide data protection for the longest period with the minimal number of used
tapes permanently loaded into a small tape library (e.g. autoloader), the best solution is to probably
choose the
Tower of Hanoi
scheme.
The
Custom
backup scheme enables you to specify a backup schedule and retention rules to define a
desired tape rotation. Use this scheme, when the
Grandfather-Father-Son
and the
Tower of Hanoi
schemes’ usage is not enough. For example, if the full size of protected data is considerably less than
the size of a tape, the best choice is to use the
Custom
backup scheme with regular
daily/weekly/monthly full backups, some simple retention rules, and tape options by default.
Criteria of the choice
Every time you are about to design a tape rotation scheme for a backup policy/plan to be created,
you ought to come from the following arguments:
full size of the data to protect
approximate size of the daily changes of data
approximate size of the weekly changes of data
requirements for the backup scheme (frequency, performance and duration of backup
operations)
requirements for keeping backups (minimal/maximal period of backup keeping; need to store
tape cartridges off-site)
