how to extract a file from media of make_tape_recovery

[chuanpeng.wang]

On one system

mt -f /dev/rmt/0m rew
mt -f /dev/rmt/0mn fsf 1
tar xvf /dev/rmt/0mn /etc/hosts
IO error.

On the other system

mt -f /dev/rmt/1mn rew
mt -f /dev/rmt/1mn fsf 1
tar tvf /dev/rmt/1mn
Tar: blocksize = 2

then
mt -f /dev/rmt/1mn rew
mt -f /dev/rmt/1mn fsf 22
tar tvf /dev/rmt/1mn It is OK.
tar xvf /dev/rmt/1mn /etc/hosts

The file is not extracted and there is no error returned.


What's the problem?
Thanks.

[Peter Godron]

Hi,
are you talking about the same tape ?
First System
fsf 1
Second System
fsf 1

then fsf 22 ??

When you say tar tvf /dev/rmt/1mn It is OK does that mean /etc/hosts is shown in the listing ?

You may need to re-position the tape to the correct fileset.

[chuanpeng.wang]

Thanks.

the sencond and third tests are on the same tape.

In the third test, I can find files, but extract it failed.

How to re-position the tape to the correct fileset?

[rariasn]

Hi chuanpeng.wang,

Possible incompatibility of dds drive on host1 and host2.

Drives and Media are only backwards compatible.

rgs.

[chuanpeng.wang]

Hi rariasn

You misunderstood.
I did the test just after make_tape_recovery on the same server.

I have two servers and two tapes.

[perumal_2]

Hi


To extract a single file from the make_tape_recovery image

use the belwo syntax
# /usr/bin/mt -t /dev/rmt/1mn rew
# /usr/bin/mt -t /dev/rmt/1mn fsf 1
# /usr/bin/tar xvf /dev/rmt/1m filename

I could see you have used 1mn, use only 1m in the last command.

TQ
Perumal

[Fabio Ettore]

Hi,

I will try to give you my thoughts:

- the method to extract files from make_tape_recovery tape is:

1) ioscan -fnCtape
be sure the device file for tape is /dev/rmt/0mn (I will suppose it is);

2) use 'no rewind' device files on both mt commands (I see you used 'mt -f /dev/rmt/0m rew' on one system, I don't know whether it is just a typo or you really used it). Anyway the right method is:

mt -f /dev/rmt/0mn rew
mt -f /dev/rmt/0mn fsf 1
tar xvf /dev/rmt/0mn etc/hosts

I wouldn't use the '/' on etc/hosts.

Try those steps and let me know if you have still problems. If you see again I/O error I would suppose you are experiencing a problem to read the tape.

Best regards,
Fabio

[Victor Fridyev]

Hi,

The sequece with fsf must work, if the tape has been created properly.

mt -f /dev/rmt/0m rew
mt -f /dev/rmt/0mn fsf 1
tar xvf /dev/rmt/0mn

The only question: there is an option in make_tape_recovery to use cpio instead of tar. Could you check this ?

HTH

[chuanpeng.wang]

mt -f /dev/rmt/0m rew
mt -f /dev/rmt/0mn fsf 1
tar xvf /dev/rmt/0mn

This is OK.
Thanks.