Data8

The 8 mm backup format is a discontinued magnetic tape data storage format used in computer systems, pioneered by Exabyte Corporation. It is also known as Data8, often abbreviated to D8 and is written as D-Eight on some Sony branded media. Such systems can back up up to 60 GB of data depending on configuration. The cassettes have the same dimensions and construction as the cassettes used in 8 mm video format recorders and camcorders.

Data8
Media typeMagnetic cassette tape
EncodingReal-time
Read mechanismHelical scan
Write mechanismHelical scan
Developed byExabyte Corporation
UsageData storage
Extended from8 mm video format
Released1987

Until the advent of AIT, Exabyte were the sole vendor of 8 mm format tape drives. The company was formed with the aim of taking the 8 mm video format and making it suitable for data storage. They did so by building a reliable mechanism and data format that used the common 8 mm helical scan video tape technology that was available then.

Exabyte's first 8 mm tape drive was made available in 1987. This was followed up with their Mammoth tape drive in 1996, and the Mammoth-2 (M2) in 1999.

Exabyte's drive mechanisms were frequently rebranded and integrated into UNIX systems.

Generations

NOTE: The AIT and VXA formats and some other less common formats also use 8 mm wide tape, but are completely incompatible.

Compatibility between tapes and drives and native capacities (GB)

MP AME AME w/ SmartClean
15 m54 m112 m160 m22 m45 m125 m170 m75 m150 m225 m
EXB-8200 YY2.4
EXB-8205 YYY
EXB-8205 XL YYYY
EXB-8500 YY5
EXB-8505 YY5
EXB-8505 XL YY57
EXB-8700 YYYY
Eliant 820 YY57
Mammoth (EXB-8900) RORORORO2.5Y1420
Mammoth-LT RORORORO2.5Y14
Mammoth-2 6123345204060

Legend:

  • RO - The tape drive can read this tape, but not write. (Read Only)
  • Y - The tape drive can read and write this tape, but size is not known.
  • Numbered entries indicate the native storage capacity (in GB) for this combination of tape and drive.

Exabyte 8 mm

These drives use metal particle (MP) tape.

EXB-8200
  • 1987—EXB-8200
    • Full-Height form factor
    • 246 kB/s data transfer rate
    • EXB-8200SX model features high-speed search
    • EXB-8205: Up to 5.0 GB on one 112 m data cartridge (assuming 2:1 compression ratio)
    • EXB-8205XL: Up to 7.0 GB on one 160 m data cartridge (assuming 2:1 compression ratio)
  • 1990—EXB-8500
    • Full-Height form factor
    • 500 kB/s data transfer rate
    • EXB-8500c model features hardware data compression
  • 1992—EXB-8505
    • Half-Height form factor
    • 500 kB/s data transfer rate (uncompressed) / 1.0 MB/s data transfer rate (assuming a 2:1 compression ratio)
    • Up to 10.0 GB on one 112 m data cartridge (assuming 2:1 compression ratio)
  • 1994—EXB-8505XL
    • Half-Height form factor
    • 500 kB/s data transfer rate (uncompressed) / 1.0 MB/s data transfer rate (assuming a 2:1 compression ratio)
    • Up to 14.0 GB on one 160 m XL data cartridge (assuming 2:1 compression ratio)
  • 1995—EXB-8700
    • Tabletop (top-loading) form factor
    • 8700 model included generic backup software
    • 8700LT model included no software
    • 8700SW included Cheyenne backup software
  • 1998—Eliant 820
    • Half-Height form factor

Mammoth

Exabyte AME tape

These drives use Advanced Metal Evaporated (AME) tape, but could also read (but not write) MP tapes.

  • 1996—EXB-8900 Mammoth
    • 3 MB/s data transfer rate
    • LCD on drive displayed drive status
  • 1999—Mammoth-LT
    • No LCD

Mammoth-2 (M2)

These drives used Advanced Metal Evaporated (AME) tape with a 2 m integrated cleaning tape header called Smart Clean.

  • 1999—Mammoth-2
    • 12 MB/s data transfer rate
    • 4.6 cm/s tape speed during normal read/write operations
    • 1.6 m/s tape speed during search and rewind operations
    • 17 s load time, from insertion to ready
    • ALDC hardware data compression, 1 kB compression buffer

See also

Standards

  • ECMA-145 ISO/IEC 11319:1991 First specification for 8 mm tape data storage.
  • ECMA-169 ISO/IEC 12246:1993, Specification of DA-1 (dual azimuth extension).
  • ECMA-249 ISO/IEC 15757, Specification of DA-2 (MammothTape).
  • ECMA-293 ISO/IEC 18836, Specification of MammothTape-2.
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