Backing up Linux system

Backup a Linux System and restore the boot mbr

rsync -aApov -S \
 --exclude={"/dev/*","/proc/*","/sys/*","/tmp/*","/run/*","/mnt/*","/media/*","/lost+found"} \
 /* /mnt/back_root/.
grub-instal /dev/sdb --root-directory=/mnt/back_root/boot