Backup

https://wiki.archlinux.org/index.php/Backup_Programs

http://etbe.coker.com.au/2012/08/08/hard-drives-backup/

Rsync

Arno's SmartBackup Script - 'intelligent' version of rsync

rdiff-backup

rdiff-backup backs up one directory to another, possibly over a network. The target directory ends up a copy of the source directory, but extra reverse diffs are stored in a special subdirectory of that target directory, so you can still recover files lost some time ago. The idea is to combine the best features of a mirror and an incremental backup. rdiff-backup also preserves subdirectories, hard links, dev files, permissions, uid/gid ownership, modification times, extended attributes, acls, and resource forks. Also, rdiff-backup can operate in a bandwidth efficient manner over a pipe, like rsync. Thus you can use rdiff-backup and ssh to securely back a hard drive up to a remote location, and only the differences will be transmitted. Finally, rdiff-backup is easy to use and settings have sensical defaults.
- man, readme, examples, wiki

http://latouche.info/admin/tips/backups/rdiff-backup_sudo.html

rdiff-backup user@server.org:[port]:/ \
  --exclude-regexp 'cache$' \
  --exclude-regexp '(?i)/te?mp$' \
  --exclude /mnt \
  --exclude /vol \
  --exclude /bak \
  --exclude /usr/media \
  --exclude /usr/media/misc \
  --exclude /usr/lib \
  --exclude /tmp \
  --exclude /var/dl \
  --exclude /var/spool \
  --exclude /var/cache \
  --exclude /proc \
  --exclude /dev \
  --exclude /sys \
/ /bak/sys