A good tools for backup Linux configuration directory like /etc.
We can use it the restore needed information and data recovery from /etc. etckeeper is a collection of tools to let /etc be stored in a git, mercurial, darcs, or bzr repository. It hooks into apt (and other package managers including yum and pacman-g2) to automatically commit changes made to /etc during package upgrades.
in reference to: etckeeper (view on Google Sidewiki)
Data Recovery Tools
Testdisk
PhotoRec
