About tar command

[juno2]

I would like to use "tar" to backup files , does "tar" support append file ? thx.

[Sridhar Bhaskarla · Accepted solution]

Hi,

Yes. Look at "u" option of tar command in it's man page.

If it is on HP system, i would suggest to use fbackup. You can do incremental backups with it and it can spawn multiple tapes.

-Sri

[Tim Adamson_1]

Yes you can do it by using the r option.

From the tar man page:

r Add the named file to the end of the archive. The same blocking factor used to create the archive must be used to append to it. This option cannot be used if the archive is a tape.


Play around with it and give it a try.


tim

[Tim Adamson_1]

I just played around by archiving to a disk tar file:

# cd /var/tmp/tim
#
# echo hello > a
# echo hello > b
#
# ll
total 4
-rw-rw-rw- 1 root sys 6 Sep 10 11:03 a
-rw-rw-rw- 1 root sys 6 Sep 10 11:03 b
#
# tar cvf ./junk.tar a
a a 1 blocks
#
# tar vrf ./junk.tar b
a b 1 blocks
# tar tvf ./junk.tar
rw-rw-rw- 0/3 6 Sep 10 11:03 2003 a
rw-rw-rw- 0/3 6 Sep 10 11:03 2003 b
#
#


Tim

[Steven E. Protter]

tar is a good backup tool for data, but it won't work on open database files like oracle.

Standard tar won't do files bigger than 2 GB. A patch from HP will bump it up to a max of 8 GB.

GNU tar has more features and the higher filesize limit.

tar cvf will create a tar archive.
tar rvf will update and add to a tar archive.

SEP