[comp.sys.ibm.pc.misc] Shelf/storage life of data on magnetic tape?

pjd@hpuxa.ircc.ohio-state.edu (Peter J. Dotzauer) (08/19/90)

What is the normal shelf/storage life of data tape cartrigdes
(specifically DC-2000 tapes).

In the case of periodic backups, this question is not relevant,
since the time between two backups is certainly much shorter than
the storage life of the data.

However, I also use the tape cartidges for archiving large data sets
that I don't always use, and that would not all fit on my hard disk
simultaneously anyway. How long can such an archive be considered
safe? After how much time can I still be reasonable sure that I can
read all the data without errors?

Perhaps, after some time, the archive should be restored, and re-written
on the same tape, or, after still more time, written on a new tape.
But what is that time span? Six months? Two Years? Five Years?

Neither the tape drive manufacturer (Colorado Memory Systems) nor the
tape cartridge manufacturer (Sony) were able to even give a hint.
All they said that the storage life of data tape depends on certain
conditions, such as temperature, humidity, etc, and following their
recommendations (no sunlight, no strong magnetic fields) would
maximize the shelf life, but they still did not say what that would be.

I have had a 2,400 ft., 9-track mainframe tape sitting for 5 years
without being even read or spun, and all data could be read without
errors. Are DC-2000 tape cartidges comparable in reliability to
mainframe tapes?
-=-
Peter Dotzauer, Analyt.Cart.& GIS, Dept.of Geogr., OSU, Columbus, OH 43210-1361
    TEL +1 614 292 1357  FAX +1 614 292 6213  FIDO 1:226/330  CCnet mapvxa::pjd
      INTERNET pjd+@osu.edu |ace for rent...this space for rent...this space f|
        BITNET pjd@ohstvmb       UUCP ...!osu-cis!hpuxa.ircc.ohio-state.edu!pjd