tar multi-volume tape

How can I list or unpack any of the archives on a multi-volume tape? Whatever I try, I can just get access of the first volume.
HarryF1Asked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

henrysCommented:
It depends on the OS - but, in general, you need to use the non-rewind tape device. F'rinstance, on a BSD-type system, that would be /dev/nrst[0,4,8,whatever] - on a SYSVR4 type system, it would be /dev/rmt/[0,1..]n.

Example (I use Solaris, so that's what this shows):
3 archives on the tape, drive /dev/rmt/0

% tar xf /dev/rmt/0n    <- gets the first file, leaves the tape at EOF
% tar xf /dev/rmt/0n    <- gets  the second file
% tar xf /dev/rmt/0     <- gets the last file, rewinds tape
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
HarryF1Author Commented:
Hello,

I'm on Linux and I use SCSI tape 0. I have the following devices which include "st0" in their name:
nrmt0, nst0, nst0a, nst0l, nst0m, rmt0, st0, st0a, st0l, st0m

I tried it with nrmt0, nst0, rmt0 and st0 but without succes. When I start tar the 2nd time I get
tar: Blocksize = 16 records
On all next starts I get
tar: Read error on /dev/xxx: I/O error
tar: At beginning of tape, quitting now

Any idea?

Harry

0
henrysCommented:
Try nst0l - this is the low-density interface to the drive. Also, try the nst0m if the other doesn't work. Was the tape written on the same system/drive as you are trying to read it on? If not, that could be the problem - especially if this is a DAT or 8mm, as there are several different drive densities "out there".
0
HarryF1Author Commented:
It might sound stupid but it still doesn't work. On nst0l and nst0m I get the message
No such device or address
On nst0 I get the same errors as described above.
It is a DAT drive but the tapes were created on the same machine with the same drive. I even can extract files from the first volume.
When I do a "mt -f /dev/nst0 status" after the first "tar tvf /dev/nst0" I get the line
block number = xxxxx
where xxxx is a number at about 70,000. As far as I can see this is ok.

Thanks for your help.
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Unix OS

From novice to tech pro — start learning today.