IBM 4mm DDS-2 Tape Autoloader, Installation And User Manual

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Operating in Harsh Environments
The 4mm DDS-2 Tape Autoloader is ideally suited to streaming operations, as
opposed to tape movement operations involving multiple stop/starts and random
searches. Streaming movement is beneficial and should be used whenever possible.
Any tape that has been used outside the ranges specified in the previous table for an
extended period of time (50 passes in 40 hours of nonstop operation) should not be
used as an archival tape. Exposure to the environment will deteriorate the magnetic
and physical strength of the tape. Do not store important data on a tape that has
been used outside the specified ranges; transfer the data to a new tape for reliable
archiving.
4mm Data Cartridge Erasure
Most bulk eraser devices do not have the capability to erase 4mm data cartridges.
To properly erase an 4mm data cartridge with a bulk eraser device, the erasure
rating must be at least 2000 oersted.
The 4mm DDS-2 Tape Autoloader erases residual data before writing new data on
the data tape.
Tape Cartridge Data Capacity
The 4mm tape cartridge capacity is defined as the amount of data that can be stored
on the cartridge. The following variables affect the amount of data that can be stored
on a tape cartridge:
Ÿ
Size of the data file
Ÿ
Number of file marks per file
Ÿ
Compatibility mode (2GB or 4GB)
Ÿ
Media rewrites
Ÿ
Nature of the data being stored. Text files are usually stored with greater
compression than binary files.
Ÿ
Cartridge format/length
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4mm DDS-2 Tape Autoloader Installation and User's Guide