etckeeper is a good utility to start tracking your changes in /etc. Of course you can initiate your own repo for your system but with etckeeper you will keep also the file permissions or the metadata.

# yum install etckeeper

You can now choose your favorite VCS, enable/disable autocommit, simply edit /etc/etckeeper/etckeeper.conf .

Want to know if something changed in /etc and is not commited ?

# etckeeper unclean ; echo $?

On a larger scale you will certainly want to use something more powerful to handle your configuration files (cfengine, puppet,…) but etckeeper is a good start and I’m usually using several alternatives just in case. 😉