How do I list all the files not owned by any package in a RPM-based system?

Question

I want to look for files polluting an old CentOS system in my company. Is there an easy way to do that?

Answer 1

If I understand correctly, you want to compare the list of all files on the system, with the list of files installed by RPMs. You should do something like this:

comm -13 <(rpm -qla | sort) <(find / -type f | sort)