We have a tape with a backup of a huge directory using the commands

chdev -a block_size=10240 -l rmt0
gtar -cvpf /dev/rmt0 home

Someone started a second dump to this tape using the same commands
but soon realized the mistake and stopped it with a <ctrl> c. Now we
are
trying to recover the original data that is beyond point on the tape
where
the second dump was stopped.

I have tried various combinations of tctl fsf, tctl fsr, dd, etc.

mt -f /dev/rmt0 rewind
dd ibs=10240 if=/dev/rmt0.1 bs=20b | tar xvpBbf 20 -

successfully retrieves the files from the beginning of tape (second
dump)
but I have not found a combination of tctl commands that get me to the
files beyond that point, e.g.

tctl -f /dev/rmt0 fsf 1

etc.

Suggestions?

Are there better commands to be using instead?

"Anthony.Weber@siemens.com" <Anthony.Weber@siemens.com> writes:

> trying to recover the original data that is beyond point on the tape
> where the second dump was stopped.

Interesting: 2 instances of the same question in one day.
See 'tar recovery needed' thread in this newsgroup.

Cheers,
--
In order to understand recursion you must first understand recursion.
Remove /-nsp/ for email.

tctl -f /dev/rmt0 fsf 1 ????

don't you want

tctl -f /dev/rmt0.1 fsf 1

to use the no-rewind driver ?

Rgds
Mark Taylor

> Are there better commands to be using instead?

Search for 'tarfix' and 'tar_aids'. They are under linux and I have no
personal experiences
with them, but they might be worth a test.

Bye, Stefan ... . . .