On 4/8/2006 at 5:48 AM Al Kossow wrote:
Not that I know of. I just think the useful life is
limited to 10-15
years. I don't think the designers of these tapes ever thought about the
need to read a tape written 20+ years in the future.
I think a big factor is the type of the medium. When I finally got my
QIC02 setup going under NetBSD, I grabbed a couple of DC6150 backup tapes
that I made back in 1991 and had stored for almost a year in the glove
compartment of my car (Why? The tapes were supposed to go into the safety
deposit box at my bank but I forgot about them). They read error-free.
When the batch of customer's tapes written in 1992 arrived (for which I'd
gone through the whole exercise) they read perfectly.
I'd need to find the backup software that I used, but it would be
interesting to see if the batch of little DC-1000 tapes that I wrote a few
years earlier still can be read on the little Irwin "floppy tape" drive I
still have.
On the "retensioning" question, I'd think that rather than using the
default of high-speed seek to end, then rewinding, I'd think it'd be better
to simply read to the end and then read in the reverse direction back to
the start. Less stress on the tape--and easy to do on the
serpentine-recorded tapes.
Cheers,
Chuck