Original message :
> Even when the amber write protect light is off, and an unprotected
DAT cassette in place, or with no cassette at all, mt status constantly
reports "DEV_WRTLCK". mt load, mt unload, etc.. does nothing.
> Is seems to have occured since an I/O error during a backup.
> Alpha server 2000, DU 4.0b, no patch
> TLZ07-LG internal (serial #3D60801581) (according to the shipping slip)
>
My thanks to :
Chris H. Ruhnke <Ruhnke_at_US.ibm.com>
Dr. Tom Blinn <tpb_at_zk3.dec.com>
John Francini <francini_at_nashua.progress.com>
who suggested to "reset device" via scu ("man scu" for details).
Unfortunately, scu cannot reset a writelocked device! Also suggested to
power cycle the whole system (this is an internal DAT...), and guessed a
faulty drive controller. Power cycling did not help whatsoever.
The answer came from DEC : I happened to use several brand new
cassettes from the same box (-> same batch), and (if I understood correctly
DEC's explanations) when you insert the cassette, the DAT drive runs a kind
of check to assess the quality of the tape. If it finds too many errors on
the tape, it marks it as wrtlckd (and keeps the device wrtlckd after
cassette removal, until a good one is inserted) to prevent use of a bad
medium. In addition, our TLZ07 is probably somewhat picky on those tapes,
because the very same cassettes were accepted without protest by an old SUN
DAT drive.
Now, I will "tapex" every cassette before use ...
Thanks to all those who maintain this list
JFL
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Jean-Francois Lafay Tel : + 33 1 69 15 62 12
Institut de Genetique et Microbiologie + 33 1 69 15 69 00
Bat. 400 Universite de Paris-Sud Fax : + 33 1 69 15 72 96
91405 Orsay Cedex - FRANCE -
Email : Jean-Francois.Lafay_at_igmors.u-psud.fr
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Received on Mon Feb 08 1999 - 13:37:53 NZDT