GNU tar

[Jestin John Chacko]

Dear ,


This is the actual output i am getting.
# /usr/local/bin/tar -cvf /dev/rmt/11mn /u01
/usr/local/bin/tar: Removing leading `/' from member names
/u01/
/u01/lost+found/
/u01/ASMT_PROD_17032009.dmp
# tar -tvf /dev/rmt/11mn
Tar: blocksize = 0; broken pipe?
# mt -f /dev/rmt/11mn rew
# tar -tvf /dev/rmt/11mn
rwxr-xr-x 0/0 0 Mar 19 12:54 2009 u01/
rwxr-xr-x 0/0 0 Jan 2 18:38 2008 u01/lost+found/
rw-rw-rw- 0/3 0 Mar 18 15:35 2009 u01/ASMT_PROD_17032009.dmp
directory checksum error
#
#


#
#
# mt -f /dev/rmt/11mn rew
# tar -xvf /dev/rmt/11mn /u02/
directory checksum error


i had tried with a small file but its working properly only problem is with this file which is nearly 18 gb

[Dennis Handly]

># tar -xvf /dev/rmt/11mn /u02/
>directory checksum error
>only problem is with this file which is nearly 18 gb

And you're sure it isn't a problem with the tape?
Can you put the tarfile on disk? If that fails, you may want to use a supported PAX-ENH instead of gtar.

[OldSchool]

"# /usr/local/bin/tar -cvf /dev/rmt/11mn /u01
/usr/local/bin/tar: Removing leading `/' from member names
/u01/
/u01/lost+found/
/u01/ASMT_PROD_17032009.dmp
# tar -tvf /dev/rmt/11mn


OK, so you used GNU tar to write the tape and probably the *normal* tar to read it? And expected this to work?

what happens when you do:

/usr/local/bin/tar -tvf /dev/rmt/11mn

?

For what its worth, I usually rename GNU tar to gtar and then add /usr/local/bin to the path....which lets me select which tar by name.

[OldSchool · Accepted solution]

and you also *didn't* rewind the tape after writing...

normally you would use /dev/rmt/11m which would rewind on completion. Unless you omitted a step in your example, you wrote the tape, left it at the end of the archive and then tried to read it. nothing to read, so it dies.

[Steven Schweda]

> And expected this to work?

Amazing, isn't it?

> and you also *didn't* rewind [...]

Ask me why I always ask to see the actual
commands used. Go ahead, ask me. I dare
you.

[Dennis Handly]

>OldSchool: you also *didn't* rewind the tape after writing.

Sure jestin did, the second and third time. :-)
Only the first time was there a "broken pipe?" message.

[Jestin John Chacko]

Dear.



1>is it necessary to rewind the tape before and after creation of an archive in tape,if so why we are using that?

2>is the same thing applicable while extracting files to a directory from a tape.

3>what is the correct format to rewind the tape?
is it mt -f rew

[Dennis Handly]

>1) is it necessary to rewind the tape before and after creation of an archive in tape, if so why we are using that?

As OldSchool said, it depends on whether you use a no rewind tape device.

If you just put in the tape, you don't need to rewind. If you are finished you should rewind, so it ejects faster.

>2) is the same thing applicable while extracting files to a directory from a tape.

The same issues. If you just wrote a no rewind tape, you need to rewind.

>3) what is the correct format to rewind the tape?
is it mt -f rew

Yes, mt(1) says that.

[Jestin John Chacko]

Now i had successfully taken the backup of 18Gb and i had restored it.thanks to all especially to u dear dennis

[Jestin John Chacko]

After installing the GNU tar along with its dependencies(libiconv&gettext)the default path should be provided

/usr/local/bin/tmp -cvf dir
for backup

/usr/local/bin/tmp -tvf for viewing

enter the current directory to which the data should be restored and provide
/usr/local/bin/tmp -xvf


for any help provide

/usr/local/bin/tmp --help