Backup using tar
Gnu tar has the nice feature of creating incremental backups. When you use incremental backups, tar creates the normal tar-file and at the same time it will also generate a special file containing a list of files, modification date, etc. If you make now a second incremental backup only files that changed regarding to the list tar made will be saved. To recover a file you need all the incremental backups and the complete first backup, since you don't know where the file will be.
Here is a sample script I use:
# backup some important files # save them on the second hard-drive # # written by Arun Persaud # 2001-10-10 MAILTO="" export MAILTO KEEP_DAYS=10 #days KEEP_WEEKS=33 #days KEEP_MONTHS=100 #days # find and delete files that are older than xyz find /backup/log/ -type f -mtime +$KEEP_DAYS -exec rm "{}" \; find /backup/daily/ -type f -mtime +$KEEP_DAYS -exec rm "{}" \; find /backup/weekly/ -type f -mtime +$KEEP_WEEKS -exec rm "{}" \; find /backup/monthly/ -type f -mtime +$KEEP_MONTHS -exec rm "{}" \; # get the Date DATE=`date +%Y-%m-%d` # complete date WEEKDAY=`date +%w` # day of the week, sunday=0 DAY=`date +%d` # day of month, 01-31 WEEK=`date +%U` # week 00-53 MONTH=`date +%m` # mont 01..12 if [ "$DAY" = "01" ] ; then DIR=monthly WEEK=m`date +%U` # dump level-0 elif [ "$WEEKDAY" = "0" ] ; then DIR=weekly else DIR=daily fi # do backup tar --create \ --file=/backup/$DIR/backup_$DATE.tgz \ --listed-incremental=/backup/log/backup_$WEEK.snar \ --verbose \ --exclude=dirs-that-should-not-be-included \ --gzip /dirs/that/should/be/included chmod 600 /backup/$DIR/backup_$DATE.tgz
The above script can be called directly from crontab.