Advanced Linux Administration & Security Lab

Lab Setup

1. Environment:

   • Use VirtualBox, Hyper-V, VMware, or a cloud-based Linux instance (Debian, Ubuntu, or CentOS).
   • Install necessary tools:

     sudo apt update && sudo apt install lynis htop tmux ufw -y
     

2. System Performance Monitoring

   • Monitor real-time system performance:

     top
     htop
     vmstat 5 10
     

3. Process & Service Management

   • List all running services:

     systemctl list-units --type=service
     

   • Restart a failed service:

     sudo systemctl restart apache2
     

4. Advanced Bash Scripting

   • Create a script to log disk space usage:

     #!/bin/bash
     df -h > /var/log/disk_usage.log
     

   • Automate it with cron:

     crontab -e
     

     Add:

     0 * * * * /home/user/disk_monitor.sh
     

5. Networking & Firewall Security

   • Check open network connections:

     ss -tulnp
     

   • Block inbound SSH (for security):

     sudo ufw deny 22
     

6. Security Hardening

   • Audit system security:

     sudo lynis audit system
     

   • Set strict file permissions:

     sudo chmod 750 /secure_data
     

7. Log Analysis & Troubleshooting

   • Find failed SSH login attempts:

     sudo journalctl -u sshd | grep "Failed password"
     

   • Monitor system logs:

     sudo tail -f /var/log/syslog
     

Lab Completion Tasks

📸 Screenshots Required:

• Running performance monitoring tools (htop, vmstat).
• A custom Bash script in action.
• Network security settings (ufw, iptables).
• Results of a security audit (Lynis).
• Log analysis of failed logins.

📝 Reflection Questions:

1. What was the most difficult part of this project?
2. How do security hardening techniques help prevent attacks?
3. How can automation improve system administration?

Next Steps

This lab reinforces real-world Linux administration and security skills. Continue exploring server hardening, automation, and intrusion detection to advance your expertise.

💾 ⬅️ Back to Project Page