27 Nov
2021
27 Nov
'21
8:43 a.m.
On second thought, given that the Worldnet outage was late 1996, it was most likely that
the backups were to 8mm tape. Exabyte?!
- Alan
On Nov 26, 2021, at 8:10 PM, Charles H. Sauer
<sauer(a)technologists.com> wrote:
I haven't done anything with 9 track tapes for a long time, but I used to help my
father with his statistical research, processing what at the time seemed massive census
and similar data sets on 9 track tape (using PL/I on 370s at U. MO Columbia). Some of his
tapes were quite old, stored in his basement and then his garage, but I don't recall
problems reading any of them.
IMNSHO, it all depends on the brand/formulation of the tape. I've been going through
old audio tapes and digitizing them
(https://notes.technologists.com/notes/2021/08/21/making-private-1960s-and-7…)
Some are over 50 years old and still seem as good to me as when they were recorded.
Others, I can anticipate from the brand/formulation that they are going to be trouble, if
salvageable at all. Most surprisingly, unbranded and similar budget tapes have survived as
well or better than some of the high-priced stuff. A few days ago I tried a reel from
1968. I was dismayed by how many times it had been spliced, but replace the splicing tape
and found it viable.
I have dozens of DDS-2, 3 & 4 cartridges from the 90s that I occasionally try to
read. I don't recall any of them failing.
(We probably should be COFFing this up.)
Charlie
On 11/26/2021 6:30 PM, Larry McVoy wrote:
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voice: +1.512.784.7526 e-mail: sauer(a)technologists.com
fax: +1.512.346.5240 Web: https://technologists.com/sauer/
Facebook/Google/Twitter: CharlesHSauer On Fri, Nov 26, 2021 at 07:23:07PM -0500, Dennis
Boone wrote:
Contrast that with the write only exabyte tapes. I lost
some stuff to those. In my experience 9 track tapes were not
guaranteed to be readable after
some interval. In fact, a standard operations procedure was to copy
important tapes to new media periodically.
There are always ways in which your backups can go wrong and not be
readable, and I'm not arguing that here.
But 9 track tapes have turned out to be pretty spectacularly long-lived.
I've personally read tapes that were stored for 30+ years in
unconditioned spaces.