1. Knowing Your Context (Avoid Costly Mistakes)
Before touching production, you must know where you are.
Context prevents accidental outages and data loss.
1. pwd # Shows current working directory
2. ls # Lists files and folders
2. Navigating Servers Without Getting Lost
Remote servers have no “Back” button.
Understanding navigation builds server confidence.
3. cd / # Go to root directory
4. cd /etc # Navigate to system config files
5. cd .. # Move one level up
3. Making Safe Changes With Backups
DevOps is about reducing risk before automation.
Backups save careers.
6. cp config.conf config.conf.bak # Create backup
4. Creating and Editing Files Like an Operator
You don’t need mastery — just survival skills.
Production rewards clarity, not fancy tools.
7. touch app.log # Create an empty file
8. vim config.yml # Edit configuration file
5. Renaming, Moving, Organizing Files
Linux efficiency beats drag-and-drop.
One command can do multiple jobs.
9. mv app.log app_old.log # Rename file
10. mv app_old.log /var/logs/ # Move file
6. Deleting Files With Respect
Linux won’t ask “Are you sure?”.
Certainty matters before pressing Enter.
11. rm file.txt # Delete a file
12. rm -r old_logs/ # Delete directory recursively
7. Understanding System Performance
Guessing is not troubleshooting.
Visibility is the start of control.
13. top # Monitor CPU, memory, processes
8. File Permiss
8. File Permissions: The Foundation of Security
Security is intentional, not accidental.
Permissions define trust.
14. ls -l # View file permissions
15. chmod 744 script.sh # Set permission levels
9. Ownership and Accountability
Access defines responsibility.
DevOps is about controlled power.
16. chown user:group file.txt # Change ownership
10. Compressing and Deploying Code
This is how code moves between environments.
Clean deployments reduce failure.
17. tar -cvf release.tar app/ # Create archive
18. tar -xvf release.tar # Extract archive
11. Working With Remote Servers
This is where DevOps truly begins.
Infrastructure replaces laptops.
19. ssh user@server_ip # Connect to remote server
20. scp build.tar user@server_ip:/home/user/ # Copy files
12. Networking Visibility
Networking stops being magic when observed.
You debug what you can see.
21. ping google.com # Test connectivity
22. netstat -tulnp # View open ports & services
13. Managing Services and Processes
This is real DevOps work.
Predictable behavior beats clever hacks.
23. systemctl status nginx # Check service status
24. systemctl restart nginx # Restart service
14. Disk Usage and Workflow Mastery
The terminal becomes honest — not scary.
Control comes from understanding.
25. df -h # Check disk usage
26. du -sh folder/ # Measure directory size
27. history # View command history
28. clear # Clear terminal
29. ps aux # List running processes
30. ls | tee output.txt # Save output to file