On 1/25/2017 6:07 PM, Charles Anthony
wrote:
On Wed, Jan 25, 2017 at 3:04 PM, Chuck Guzis<ccl...@sydex.com> wrote:
On 01/25/2017 02:16 PM, Eric Smith wrote:
On Jan 25, 2017 12:24 PM, "Stan Sieler"<sie...@allegro.com> wrote:
We have a friend with a "tape" (DDS, DLT, or LTO ... don't know
which yet) to which was written a system backup. Thousands of
files, with an EOF between each file, and a double EOF + EOT at the
end.
The problem: They then accidentally overwrote the start of the tape
yesterday with about 1 KB of data, plus EOT.
I hope someone can prove me wrong, but I think that short of a major
effort to hack the drive firmware, the data is gone. Modern tape
drives are "too smart" to allow reading past logical EOT, and the
tape format is too complex to allow fooling the firmware by any
simple means.
With nothing left to lose, I suppose that one might overwrite the EOT
and then kill power during the write, then attempt to read backward from
the end of the tape.
I've never done it, but who knows?
Or do it the data recovery way -- find a broken drive with a working
transport, hookup a A/D to the tape heads, stream the tape, capture the
flux, decode.
Not necessarily easy, tho.
-- Charles
Would it be possible to just physically
cut the 1kb + EOT portion of tape out,
and then attempt to read from
beginning? I suppose this would depend
on how the backup data is formatted on
the tape (using some kind of container
format with error checking, for instance).
- J.
