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♜ LINUX HARDENING LAB
SSH CONFIGURATION · FIREWALL RULES · ACCESS CONTROL · SECURITY MONITORING
STATUS: ACTIVE
PROJECT OVERVIEW
The Linux Hardening Lab is the foundation of The Citadel project. It focuses on configuring
and securing an Ubuntu Linux environment for remote administration, public hosting, and
security operations practice.
IMPLEMENTED CONTROLS
- Configured SSH for remote Linux administration.
- Enabled UFW firewall rules to control inbound traffic.
- Tested public hosting through Apache before migrating to Docker and NGINX.
- Connected the environment to Cloudflare Tunnel to avoid traditional port forwarding.
- Started authentication monitoring using Linux SSH logs and journald.
SECURITY VALUE
This lab demonstrates hands-on Linux administration, basic host hardening, firewall
management, remote access control, and the beginning of authentication telemetry.
COMMAND AREAS PRACTICED
systemctl status ssh
sudo ufw status verbose
journalctl -u ssh
tail -f /var/log/auth.log
sudo docker ps
CURRENT CAPABILITIES
- SSH access configured for remote Linux administration.
- UFW firewall enabled to control inbound traffic.
- Fail2Ban protection configured for SSH hardening.
- Authentication logs monitored through journald and auth.log.
- Dockerized NGINX web stack deployed locally.
- Cloudflare Tunnel used for public access without traditional port forwarding.
- Operations Dashboard displaying live uptime, CPU, memory, disk, Docker, and Git telemetry.
STATUS
Active and operational. The Linux Hardening Lab serves as the foundation of The Citadel,
providing secure remote administration, firewall enforcement, containerized hosting,
Cloudflare connectivity, and operational monitoring.
CURRENT CAPABILITIES
- SSH access configured for remote Linux administration.
- UFW firewall enabled to control inbound traffic.
- Fail2Ban protection configured for SSH hardening.
- SSH authentication events monitored through journald and auth.log.
- Dockerized NGINX web stack deployed locally.
- Cloudflare Tunnel used for public access without traditional port forwarding.
- Operations Dashboard displaying live uptime, CPU, memory, disk, Docker, and Git telemetry.
NEXT OBJECTIVES
- Integrate live Fail2Ban metrics into the Operations Dashboard.
- Surface SSH authentication metrics including successful logins, failed attempts, and source IPs.
- Create a dedicated authentication monitoring dashboard card.
- Organize screenshots and milestone evidence into formal documentation.
- Create architecture diagrams for infrastructure and traffic flow.