Quantum Scalar 1000, Руководство оператора

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Cleaning Drives 6-21
22 June 2004
Some host applications cannot tell when the drive requires
cleaning, so they implement cleaning by a load or mount
count (for example, after every 50 tape loads or mounts to the
drive).
If the load count is too small, it results in unneeded drive
cleaning which results in unnecessary head wear, which
shortens the life of the drive.
If the load count is too big, the drive may require cleaning but
not receive it. This results in dirty heads during read/ write
operations and possibly lost data.
Disadvantage:
This procedure extends the time to move media from a drive
to a storage position. Some drives can take more than 5
minutes to clean. If the host application cannot wait that long,
the move operation that contained the cleaning operation
fails.
Library storage slots are used for cleaning tapes. If you cannot
spare storage slots in the library then you should use manual
cleaning without library tapes.
Library Delayed AutoClean
You must have at least one good cleaning tape entered into the
library before beginning this procedure. For further
information, refer to Inserting a Cleaning Cartridge on page 25
or Declaring a Cleaning Cartridge on page 27.
Use this procedure to clean your drives at a time of your
choice if all of the following are true:
• Host application does not perform drive cleaning
• Host timeout for moves from the drives is too short to
include cleaning
• The host timeout for moves cannot be extended
At your preset time, the library checks the drive. If the drive
reports to the library that it requires cleaning, and AutoClean
is enabled, and the drive is empty, the library selects the
cleaning tape and inserts it into the drive.
After the cleaning process is complete, the tape is ejected,
moved back to storage, and the use counter is incremented.
Advantage:
Provides extended drive life because it prevents a weak tape
from being mistaken for a dirty drive and prevents cleaning
the drive too frequently. For additional information, refer to
Immediate AutoClean on page 20.
Note
Be aware that most
cleaning cartridges are
abrasive and burnish
the heads of the drive
they are cleaning.
Burnishing causes
wear on the tape drive
heads. Cleaning too
frequently can reduce
the life of a tape drive.