Backup and restore with tar

[rana786]

Hi there,

I like to take backup some of our file system using “tar” and append data daily basis in same cartridge but I did not find any parameter in man page. would you please check that whether it is possible or not.

Here I like to mention that from this backup I have to restore frequently so please give me the total procedure of backup(with append) and restore.

Mostafa

[Julio Yamawaki]

Hi,

To append a backup in a tape with tar use mt command.
For example, in the first time, just use tar cvf /dev/rmt/xm /backup
second time:
mt -t /dev/rmt/xm fsf 1 --> 1 indicates first tape mark and so on 2,3,4...
after mt, just use tar cvf, but be very carefull, because every time you tar something to tape, if you use xm tape will rewind and the next time you want to write something, you must use mt first.

Regards,

[Victor Fridyev]

Hi,

I'm not sure that a backup on a tape using tar is good idea, especially if you want to add files daily. The problem is not in the backup, the problem is in restore. You have to know which tar file on the tape contains the file which you like to restore. In order to know that, you have to support a database with a list of backed up files etc.
Theoretically it's interesting and relatively simple to create such a backupsystem, but practically it's much easier and not very expensive to buy something like backupexe or similar.

HTH

[Ivan Ferreira · Accepted solution]

Use the no rewind /dev/rmt/Xmn device:

First backup:

tar cvf /dev/rmt/0mn

Second backup

tar cvf /dev/rmt/0mn

Restore first backup

mt -f /dev/rmt/0mn rewind

tar xvf /dev/rmt/0mn

Restore second backup

mt -f /dev/rmt/0mn fsf 1

tar xvf /dev/rmt/0mn


And so on...

[rana786]

Its ok.