Operation Manual

198 Copyright © Acronis International GmbH, 2002-2015
When you use the Simple backup scheme (p. 61), only full backups can be created on tapes. This is
because backups located on tapes cannot be consolidated (p. 437). If you had the option of creating
incremental backups, you would not be able to delete any of the backups.
Grandfather-Father-Son and Tower of Hanoi schemes
By default, the Grandfather-Father-Son (p. 62) and Tower of Hanoi (p. 68) backup schemes create
only full backups on tapes. This helps the software to delete each backup on time as defined by the
backup scheme.
You may want to change the default setting to creating full, incremental and differential backups. For
example, if you have a few tapes but your full backups are quite large, you may want to save space
on tapes.
Each level of the above schemes uses a separate tape set within the same tape pool. This means that
the software can only take a tape belonging to a certain tape set or a free tape (when space is
running out on the currently used tape). This helps minimize the quantity of used tapes, because
tapes with incremental and differential backups are filled and rewritten more often than tapes with
full backups.
Custom scheme
Set up the custom scheme so that it creates full backups with a reasonable frequency. Otherwise, if
you specify retention rules, the software will not be able to overwrite tapes as appropriate.
In the retention rules of the Custom backup scheme (p. 65), the If a backup to be moved or deleted
has dependencies: Consolidate these backups option is disabled. Only the Retain the backup until
all dependent backups become subject to deletion option is available. This is because backups
located on tapes cannot be consolidated (p. 437).
7.4.2.6 Parallel operations
Acronis Backup can simultaneously perform operations with various components of a tape device.
During an operation that uses a drive (backing up, recovering, rescanning (p. 208), or erasing (p. 208)),
you can launch an operation that uses a changer (moving (p. 207) a tape to another slot or ejecting (p.
208) a tape) and vice versa. If your tape library has more than one drive, you can also launch an
operation that uses one of the drives during an operation with another drive. For example, several
machines can back up or recover simultaneously using different drives of the same tape library.
The operation of detecting the new tape devices (p. 204) can be performed simultaneously with any
other operation. During inventorying (p. 210), no other operation is available except for detecting the
new tape devices.
Operations that cannot be performed in parallel are queued.
7.4.2.7 Limitations
The limitations of tape device usage are the following:
1. The consolidation (p. 437) of backups located on tapes is not possible. As a result, usage of
backup schemes has certain peculiarities (p. 197).
2. The deduplication (p. 438) of backups located on tapes is not possible.
3. Simplified naming of backup files (p. 73) is not possible for backups stored on tapes.
4. You cannot recover under an operating system from a backup stored on tapes if the recovery
requires the operating system reboot. Use bootable media to perform such recovery.