114 lines
3.7 KiB
ReStructuredText
114 lines
3.7 KiB
ReStructuredText
Tape Backup
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===========
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Our tape backup solution provides a easy way to store datastore
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contents on a tape. This increases data safety because you get:
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- an additional copy of the data
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- to a different media type (tape)
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- to an additional location (you can move tape offsite)
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Tape backups do not provide random access to the stored
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data. Instead, you need to restore the data to disk before you can
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access it again.
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Tape Technology Primer
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----------------------
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.. _Linear Tape Open: https://en.wikipedia.org/wiki/Linear_Tape-Open
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As of 2021, the only broadly available tape technology standard is
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`Linear Tape Open`_, and different vendors offers LTO Ultrium tape
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drives and autoloaders.
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In general, LTO tapes offer the following advantages:
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- Durable (30 years)
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- High Capacity (12 TB)
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- Relatively low cost per TB
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- Cold Media
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- Movable (storable inside vault)
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- Multiple vendors (for both media and drives)
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Supported Hardware
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------------------
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Proxmox Backup Server supports `Linear Tape Open`_ genertion 3
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(LTO3) or later. In general, all SCSI2 tape drives supported by
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the Linux kernel should work.
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Tape changer support is done using the Linux 'mtx' command line
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tool. So any changer devive supported by that tool work work.
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Drive Performance
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~~~~~~~~~~~~~~~~~
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Current LTO8 tapes provide read/write speeds up to 360MB/s. Please
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note that it still takes a minimum of 9 hours to completely write or
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read a single tape (even at maximum speed).
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The only way to speed up that data rate is to use more than one
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drive. That way you can run several backup jobs in parallel, or run
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restore jobs while the other dives are used for backups.
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Terminology
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-----------
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:Tape Labels: are used to uniquely indentify a tape. You normally use
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some sticky paper labels and apply them on the front of the
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cartridge. We additionally store the label text magnetically on the
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tape (first file on tape).
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.. _Code 39: https://en.wikipedia.org/wiki/Code_39
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.. _LTO Ultrium Cartridge Label Specification: https://www.ibm.com/support/pages/ibm-lto-ultrium-cartridge-label-specification
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:Barcodes: are a special form of tape labels, which are electronically
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readable. Most LTO tape robots use an 8 character string encoded as
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`Code 39`_, as definded in the `LTO Ultrium Cartridge Label
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Specification`_.
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You can either bye such barcode labels from your cartidge vendor,
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or print them yourself.
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.. Note:: Physical labels and the associated adhesive shall have an
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environmental performance to match or exceed the environmental
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specifications of the cartridge to which it is applied.
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:Media Pools: A media pool is a logical container for tapes. A backup
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job targets one media pool, so a job only uses tapes from that
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pool. The pool aditionally defines how long we can append data to a
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tape (allocation policy), and how long we want to keep that data
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(retention policy).
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:Tape drive: The decive used to read and write data to the tape. There
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are standalone drives, but drives often ship within tape libraries.
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:Tape changer: A device which can change the tapes inside a tape drive
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(tape robot). They are usually part of a tape library.
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.. _Tape Library: https://en.wikipedia.org/wiki/Tape_library
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:`Tape library`_: A storage device that contains one or more tape drives,
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a number of slots to hold tape cartridges, a barcode reader to
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identify tape cartridges and an automated method for loading tapes
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(a robot).
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People als call this 'autoloader', 'tape robot' or 'tape jukebox'.
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Tape Quickstart
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---------------
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1. Configure your tape hardware (drives and changers)
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2. Configure one or more media pools
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3. Label your tape cartridges.
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4. Start your first tape backup job ...
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