best way to protect config.php file?

[D Oliveira]

Hello all, while implementing https://www.commentics.org/ (demo:) https://www.commentics.org/demo I have came across the task of handling a new config.php file that is located on my appfolder/commentics/config.php, so my question is, how can I secure that file since its far from main directory while it has sensitive db access information? A simple change of permissions on the server will do the job?