Editing Tape library (section)

== Automated era ==
[[File:StorageTek Powderhorn tape library.jpg|thumb|upright=0.7|Large [[StorageTek]] Powderhorn tape library, showing tape cartridges with barcodes packed on shelves in the front and a robot arm moving in the back]]
[[File:ADIC Scalar 100 tape library.jpg|thumb|upright=0.6|Small [[Advanced Digital Information Corporation|ADIC]] Scalar 100 tape library, showing a robot visible on the bottom with two [[IBM LTO2]] tape drives behind it]]

=== Design ===

Physically automated tape library devices can store immense amounts of data, ranging from 20 [[terabyte]]s<ref>{{Cite web|url=http://h18006.www1.hp.com/products/storageworks/msl2024/index.html|title=HP StorageWorks MSL2024 Tape Library - overview|date=March 18, 2006|access-date=June 19, 2018|archive-date=March 18, 2006|archive-url=https://web.archive.org/web/20060318182700/http://h18006.www1.hp.com/products/storageworks/msl2024/index.html|url-status=bot: unknown}}</ref> up to 2.1 [[exabyte]]s of data<ref>[[Oracle Corporation|Oracle]] {{cite web|url=http://www.oracle.com/us/products/servers-storage/storage/tape-storage/sl8500-modular-library-system/overview/index.html|title=StorageTek SL8500 Modular Library System}}</ref> as of 2016.  Such capacity is multiple thousand times that of a typical [[hard drive]] and well in excess of what is capable with [[network attached storage]]. Typical entry-level solutions cost around $10,000 USD,<ref>[http://h71016.www7.hp.com/dstore/ctoBases.asp?jumpid=re_NSS_msl2024&ProductLineId=450&FamilyId=2297 HP Small & Medium Business Online Store: HP StorageWorks MSL2024 Tape Libraries]</ref> while high-end solutions can start at as much as $200,000 USD<ref>[http://www.oracle.com/us/products/servers-storage/storage/tape-storage/sl8500-modular-library-system/overview/index.html]. Cites cost as "From $195,830. (US)"</ref> and cost well in excess of $1 million for a fully expanded and configured library.

For large data-storage, they are a cost-effective solution, with cost per gigabyte as low as 2 cents USD.<ref>{{cite web|url=https://www.forbes.com/sites/tomcoughlin/2016/07/24/the-costs-of-storage/#29cedc803239|title=The Costs Of Storage|work=Forbes}}</ref> The tradeoff for their larger capacity is their slower access time, which usually involves mechanical manipulation of tapes.  Access to data in a library takes from several seconds to several minutes.

Because of their slow sequential access and huge capacity, tape libraries are primarily used for [[backup]]s and as the final stage of [[digital archiving]]. A typical application of the latter would be an organization's extensive transaction record for legal or auditing purposes. Another example is [[hierarchical storage management]] (HSM), in which tape library is used to hold rarely used files from [[file system]]s.

=== Software support ===

There are several large-scale library-management packages available commercially. Open-source implementations include [[Advanced Maryland Automatic Network Disk Archiver|AMANDA]], [[Bacula]], and the minimal mtx program.

=== Barcode labels ===

Tape libraries commonly have the capability of optically scanning [[barcode]] labels which are attached to each tape, allowing them to automatically maintain an inventory of which tapes are where within the library. Preprinted barcode labels are commercially available or custom labels may be generated using commercial or free software. The barcode label is frequently part of the [[tape label]], information recorded at the beginning of the medium to uniquely identify the tape.

=== Autoloaders ===
[[File:Powervault 124T autoloader.jpg|thumb|left|Dell PowerVault 124T Autoloader]]

Smaller tape libraries with only one drive are known as autoloaders.<ref>{{cite web|url=http://www.snia.org/education/dictionary/t|quote=tape autoloader...[Storage System] A tape device that provides automated access to multiple tape cartridges, typically via a single tape drive.|title=SNIA Dictionary|publisher=Storage Network Industry Association|accessdate=2010-01-30}}</ref> The term ''autoloader'' is also sometimes used synonymously with ''stacker'',<ref>{{cite web|url=http://www.sunhelp.org/faq/backup.html#korea10|quote=What is a stacker (autoloader) vs a jukebox?|title=Ten common backup/restore related questions|publisher=Sun Microsystems, Inc|accessdate=2010-01-30}}</ref> a device in which the media are loaded necessarily in a sequential manner.<ref>{{cite web|url=http://www.snia.org/education/dictionary/m|quote=media stacker...[Data Recovery] A robotic media handler in which media must be moved sequentially by the robot.|title=SNIA Dictionary|publisher=Storage Network Industry Association|accessdate=2010-01-30}}</ref>

Other types of autoloaders may operate with [[optical disc]]s (such as [[compact disc]]s or [[DVD]]s) or [[floppy disk]]s{{citation needed|date=October 2011}}.