Linux Fundamentals Part Three Lecture Notes

Introduction

• Final part of the Linux Fundamentals series.
• Focuses on utilities and applications for daily use.
• Covers automation, package management, and logging.

Task 1: Introduction

• Review of fundamental concepts and important commands.
• Introduction to useful utilities and applications.

Task 2: Deploying the Machine

• Deploy the machine attached to the task.
• SSH into the machine using provided credentials.

Task 3: Terminal Text Editors

• Nano: Easy to start, basic features like search (Ctrl+W), copy/paste, exit (Ctrl+X).
• Vim: Advanced features like customizability, syntax highlighting, and widespread availability.
• Editing files using Nano.
  • Example: Create/edit a file with nano filename.

Task 4: General/Useful Utilities

• Downloading Files: Using wget to download via HTTP.
• Transferring Files: Using scp for secure file transfer via SSH.
• Serving Files: Use Python's HTTP server module.
  • Example command: python3 -m http.server

Task 5: Processes 101

• Viewing Processes: Use ps and top for detailed process information.
• Managing Processes: Use kill to terminate processes with specific PIDs.
• Understanding Process IDs: PID increments with each new process.
• Namespace and Init Systems: Systemd manages user processes.
• Starting Services on Boot: Use systemctl for managing services.
• Backgrounding and Foregrounding:
  • Background: Append & or use Ctrl+Z.
  • Foreground: Use fg.

Task 6: Automation with Cron

• Cron Jobs: Schedule tasks with crontab using specific time formats.
• Editing Crontabs: Use crontab -e to open and edit.

Task 7: Package Management

• APT Repositories: How to manage and add new repositories.
• Installing/Removing Software: Use apt for package management.
  • Example: apt install and apt remove.

Task 8: System Maintenance with Logs

• Log Files: Found in /var/log. Important for monitoring system health.
• Apache Logs: Access and error logs for web server tracking.

Conclusion

• Linux is powerful with ease of use through practice.
• Continue learning via additional TryHackMe rooms on Linux tools like Bash scripting, regex, and the find command.