How to install AIDE on CentOS
3) Securing AIDE Conf & DB:
Store /etc/aide.conf, /usr/sbin/aide and /var/lib/aide/aide.db.new.gz in a secure location, e.g. on separate read-only media (such as CD-ROM). Alternatively, keep MD5 fingerprints or GPG signatures of those files in a secure location, so you have means to verify that nobody modified those files.