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8-19
Using Mass Storage Devices
DDS Tape Drive and Data Cassette Descriptions
If the LED indicators on your DDS-format drive display the Media Wear
(Caution) condition, follow this procedure:
1
Check the system console for any tape error messages. A hard error during
a read or write operation may have occurred.
2
Clean the heads with a cleaning cassette (HP92283K) as described in
“Cleaning the Tape Heads,” later in this chapter.
3
Repeat the operation you performed when the Media Wear (Caution) sig-
nal displayed. If the Media Wear (Caution) signal still displays, then the
data cassette should be replaced.
4
If you are performing a backup from disk to tape, discard the data cassette
and back up your files using a new data cassette.
5
If you are performing a restore from tape to disk, complete the restore,
back up the files to a new data cassette, then discard the data cassette.
Data Cassettes
Media Life
HP DDS data cassettes are currently specified to 2000 passes over any part
of the tape under optimal environmental conditions (50% relative humidity,
22 degrees C). During a tape operation, any one area of the tape may have
multiple passes over the heads. This translates into approximately 200 to 300
backups or restores.
Under certain conditions, the life of your data cassette is less. Replace your
data cassettes after 100 backups or restores if your operating conditions meet
any of the following criteria:
• The relative humidity in your operating environment is consistently less
than 50%.
• You know that the backup software you are using makes multiple passes
over sections of the tape during backups or restores.
• You notice that when you do backups and restores the tape stops and starts
frequently.