UNIX for Dummies Questions & Answers

How do I use tar to backup files to tape. I saw the man page but found it too confusing

Thanx
Kavita

Check the man page again. There are examples in it which are rather easy to understand.

To create a tar use the c option.
To extract a tar, use the x option.
To view what is in a tar file, use the t option (with v)
The v option gives you verbose mode.
The f option allows you to name the file to create, extract, or view


Example from tar man page:
The following is an example using tar to create an
archive of your home directory on a tape mounted on drive
/dev/rmt/0:

example% cd
example% tar cvf /dev/rmt/0 .
messages from tar

The c function letter means create the archive; the v
function modifier outputs messages explaining what tar is
doing; the f function modifier indicates that the tarfile
is being specified ( /dev/rmt/0 in this example). The dot
(.) at the end of the command line indicates the current
directory and is the argument of the f function modifier.

I managed to tar my export files to tape with the foll command:
tar -cvf /dev/rmt/0 expnew.dmp
and after that when I do a tar -tv
I am able to see the file.
But today again I tarred 2 exp files to tape
with
tar -cvf /dev/rmt/0 expnew.dmp expnew2.dmp
it worked fine and the exit value was 0 but when I run the foll commands to see a listing:
tar -tvf /dev/rmt/0
tar -tv
I get tar:tape read error

What does this mean, please help!!
thanx

Any clues guys please help..

Thanx

1. Make sure the tape is in the drive (really, this happens!)
2. check the man page on the mt command - use this to insure the tape is rewound.
3. Always read the man pages - pay attention to the "SEE ALSO" portion as you may get more help from a different command.

FYI - it doesn't look like you did anything wrong with your commands but I don't have a tape drive to test with.