Hardening
- Cromwell Base - http://www.cromwell-intl.com/cybersecurity/linux-hardening.html
- Practical Guide - https://github.com/trimstray/the-practical-linux-hardening-guide
- inspec - https://github.com/inspec/inspec
- LikeGeeks - Quick Overview - https://likegeeks.com/secure-linux-server-hardening-best-practices/