Tripwire is a data integrity tool for monitoring and alerting file and directory changes.
https://github.com/Tripwire/tripwire-open-source
To install, run
yum install tripwire
Generate keys
Run
tripwire-setup-keyfiles
This ask you to enter password.
Creating Database
tripwire --init
You need to edit file
vi /etc/tripwire/twpol.txt
customise it for your system or you may get file/directory not found errors.
Checking for changes
tripwire --check