[ Thanks to Amy Newman for this link.
]
“Etckeeper is a set of tools that lets you keep your /etc
directory (and all the configuration files under it) in a revision
control systems. You can use it with Git, Mercurial, Darcs or
Bazaar. Note that you’ll need to know the basics of whatever system
you choose to use because etckeeper doesn’t have special utilities
for restoring older versions of files.“You could easily set up /etc with revision control without
etckeeper. However, the advantage of etckeeper is that it’s
designed specifically for tracking /etc, including the file
permissions and metadata that the revision control systems do not
track.”