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one or more loaders (robotic mechanisms) intended for relocating the tape cartridges between
the slots and the tape drives
barcode readers (optional).
Each tape may have a special label attached to the side of a cartridge and comprise of:
a barcode to scan by a special reader that is usually mounted on a loader
a readable barcode digital value.
Such labels are used for tape identification in a tape library or especially in off-site storage.
If all cartridges in a tape library have barcodes, the library is ready to be automatically managed by
software.
Tape libraries are a cost-effective solution for data storages with huge capacity. Moreover, tape is
perfect for archiving because cartridges can be stored off-site for enhanced data security. However
reading even a small amount of data from a tape library takes much more time (from several seconds
to several minutes) than from other types of data storages. The best practice of tape usage is "LESS
requests to write/read LARGER amount of data". So systematic access to very large quantities of data
is more suitable for a tape library than random access to small portions of data.
4.1.3.3
Limitations
Limitations of tape library usage are the following:
1.
The consolidation (p. 365) operation is not possible for archives located on tapes. Deletion of a
single separate backup is impossible from a tape. It is possible to delete all the backups stored on
a tape. However, after this operation all the incremental and differential backups, stored on
other tapes and based on the deleted backups, cannot be used for data recovery. In a
Custom
backup plan's retention rules the
If deletion of a backup affects other backups > Consolidate the
backup
option is disabled. Only the
Postpone the deletion
option is available.
2.
Deduplication (p. 365) is not available for archives located on tape storage devices.
3.
File recovery from a disk backup stored on tape is possible, but can take a very long time.
4.
A tape with backups written by the storage node cannot be read on a tape device, locally
attached to a machine, the agent is installed on, because of a difference in tape format. To get
information about the readability of the archives on tapes, written by different components of
other versions of the product by means of Acronis Backup & Recovery 10, see the Tape
compatibility table (p. 47) section.
5.
Barcode printers are not used.
4.1.3.4
RSM Media Pools
Acronis Backup & Recovery 10 uses Windows Removable Storage Manager (RSM) to manage tape
cartridges belonging to tape libraries.
To separate access to media by different programs the RSM uses so called Media Pools that are
logical media groups. There are two categories of media pools in the manager:
System
and
Application
.
System
media pools include
Free
pool,
Import
pool and
Unrecognized
pool. The
System
pools hold
media that are not currently used by applications. The
Free
pool holds media that are considered as
free and can be used by applications. The
Import
and
Unrecognized
pools are temporary pools for
media that are new in certain library.
