I would like to backup my server that is hosting a few websites in such a way that I can restore everything to the way it was from a fresh format. I know that I should backup all the home folders and then probably my /etc/ folders. Is there a way to figure out all the folders that are relevant for backup in that they were not automatically generated or installed from apt-get? It would ideally restore all the users with their current passwords as well. Basically, enough to clone the system but only copying configuration files.