Cleaning Exabyte drives?

[Paul Eggert]

Mark Plotnick asks:

|Does the 30-days-or-30-GB rule apply to drives in which the tape is ALWAYS
|left loaded?...  I fear this practice does a much better job of
|magnetizing and depositing oxide on the head.

We asked Exabyte about this, and they said it's not a problem.  If the
tape doesn't move for five seconds, the tape path becomes untensioned; and
if this persists for a minute, the drum stops rotating.

|The funny thing is, we didn't really start to see the "tape may be wearing
|out or the head may need cleaning" messages until after we started using
|the cleaning cartridge.

We also saw more of these messages as time went on.   They seem
independent of tape age, but correlated with which particular tape is
being used.  The tape is not necessarily wearing out: it may just be a bit
below spec, and perhaps the drive gets more finicky with time.  Exabyte
sells tapes that are rumored to be of higher quality, but they are much
more expensive than our normal Sony P6-120MP tapes.  So far, we've had no
problems other than the warning messages, which we have observed up to
fifty times per tape.