dar est un utilitaire sous linux permettant de réaliser des sauvegardes simple avec quelques fonctions avancées comme :

• la gestion des sauvegardes complètes et incrémentales
• le support du chiffrement des données
• la compression des données

Cette page décrit comment l'utiliser ponctuellement ou de manière automatisée.

#!/bin/sh

# Dar backup script
# Matthieu Bouthors
# http://www.bouthors.fr
# licence GPLv2

# location of files
config_dir=/home/scripts
# temporary file
run_file=archive_gandalf_running
# dar options (DCF format)
dar_options=gandalf.dcf
# file that save the last full backup
last_backup_file=last_dar
# destination folder
archive_dir=/data/backup


case "$1" in
  full)
        if [ -e "$config_dir/$run_file" ]
        then
                echo archive already running
        exit 1
        fi
        touch "$config_dir/$run_file"

        archive_file="full_`date +%Y%m%d_%H%M%S`"
        echo $archive_file
        /usr/bin/dar -c $archive_dir/$archive_file -B $config_dir/$dar_options
        if [ $? -eq 0 ]
        then
                echo "$archive_dir/$archive_file" > $config_dir/$last_backup_file
                rm -f "$config_dir/$run_file"
                exit 0
        fi
        rm -f "$config_dir/$run_file"
        exit $?
        ;;
  inc)

        if [ ! -e "$config_dir/$last_backup_file" ]
        then
                echo no previous dar
        exit 1
        fi

        old_dar=`cat $config_dir/$last_backup_file`
        echo reference dar : $old_dar

        if [ ! -e "$old_dar.1.dar" ]
        then
                echo previous dar not found
        exit 1
        fi

        if [ -e "$config_dir/$run_file" ]
        then
                echo archive already running
        exit 1
        fi
        touch "$config_dir/$run_file"

        archive_file="inc_`date +%Y%m%d_%H%M%S`"
        echo $archive_file
        /usr/bin/dar -c $archive_dir/$archive_file -A $old_dar -B $config_dir/$dar_options
        if [ $? -eq 0 ]
        then
                rm -f "$config_dir/$run_file"
                exit 0
        fi
        rm -f "$config_dir/$run_file"
        exit $?
        ;;

  kill)
        killall dar
        rm -f "$config_dir/$run_file"
        exit 0
        ;;
  *)
        echo "option : full, inc"
        exit 1
esac
exit 0

Voici un script permettant de supprimer les sauvegardes trop vielles

#!/bin/sh

# Dar cleanup script
# Matthieu Bouthors
# http://www.bouthors.fr
# licence GPLv2

#folder to watch :
watch_folder=/data/backup/

# delete inc files older than inc_keep days :
inc_keep=60
# delete full files older than full_keep days :
full_keep=180

now=`date +%s`
limit_keep=$(($now-($inc_keep*86400)))

for filename in `ls $watch_folder/inc*.dar`
do
        find_date_text=`expr match $filename '.*/inc_\([0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]\)_'`
        date_file=`date -d $find_date_text +%s`
        if [ $date_file -lt $limit_keep ]
        then
                /bin/rm -vf $filename
        fi
done


limit_keep=$(($now-($full_keep*86400)))


for filename in `ls $watch_folder/full*.dar`
do
        find_date_text=`expr match $filename '.*/full_\([0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]\)_'`
        date_file=`date -d $find_date_text +%s`
        if [ $date_file -lt $limit_keep ]
        then
               /bin/rm -vf $filename
        fi
done