Quantum DLTtape DLT 2000, Руководство пользователя

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Each library maker has their own tape handling mechanism. Some
of the different mechanisms you’ll find include robotic arms, eleva-
tors, and carousels. Some libraries are equipped with multiple mech-
anisms.
Another feature to look for in larger libraries is a “mailbox.” This is a
slot or compartment at the front of the system that allows the opera-
tor to load one or more tapes without opening the main door and
interrupting library activity. The key characteristics to look for in the
tape handling mechanism are proven performance over time (reliabil-
ity), tape load/unload speed, and extra features like pass-through tape
handling. A pass-through capability allows multiple libraries to be
connected and share tape cartridges. This is especially important in
high availability applications in which a requested tape can be passed
between libraries to the next available drive. A proper drive-to-car-
tridge ratio can also provide high availability in most situations.
Library and loader controllers. Most libraries contain two physi-
cally-separate control devices to oversee overall library activity, as
well as loader movement. Both of these control devices are
equipped with microprocessors, local memory, and other electron-
ics. Both devices communicate with library components and the
host computer via a SCSI interface. The loader controller follows
the directions of the library controller or the tape drive itself.
Power supply. Features you should look for in a power supply are
autoranging and growth capacity. If there’s a chance you may need
to ship your library to Europe, you may want to look for an auto-
sensing power supply that automatically adjusts for U.S. or
European voltage (110 volts vs. 240 volts). If the library or loader
you’re considering is expandable, you should ask if the standard
power supply can handle additional drives, or does it have to be
replaced to accommodate them.
AUTOMATION 8.10