June 30, 2026

100 Days of Change: Day 2 — Mastering the Engine

“Efficiency is doing things right; effectiveness is doing the right things.” — Peter Drucker

By Mudassir.Sharif

1 min read

Day 2 of my Cyber Security 101 path on TryHackMe is officially in the books. Yesterday, we laid the foundation with basic navigation; today, we popped the hood to see how a Linux system actually runs.

If Day 1 was about moving around, Day 2 was about controlling the environment.

What I Learned Today

The transition from a "user" to a "sysadmin" mindset starts with understanding how the operating system handles tasks, files, and automation. Here is what I dug into:

  • Text Editing: I leveled up my terminal efficiency by practicing nano for quick edits and getting my first real taste of vim for more robust text manipulation.
  • Secure File Transfers: I explored how to move data safely across networks using scp and learned the clever trick of using Python's built-in http.server to host files locally for quick access.
  • Process Management: I learned that understanding a system means seeing what's running inside it. Knowing how to monitor processes (ps, top) and how to gracefully — or forcefully — terminate them (kill) is essential for maintaining system stability.
  • The Power of Automation: I touched on crontab. The ability to schedule repetitive tasks is a superpower, turning a manual chore into a "set it and forget it" system maintenance routine.
  • The Power of Automation: I touched on crontab. The ability to schedule repetitive tasks is a superpower, turning a manual chore into a "set it and forget it" system maintenance routine.
  • Software Lifecycle: Finally, I demystified package management. Understanding apt and how to interact with repositories is the backbone of keeping a secure and up-to-date environment.

Why This Matters

In cybersecurity, we don't just use tools; we interact with the infrastructure hosting them. Mastering these commands is the difference between blindly executing a script and understanding exactly how that script is interacting with the underlying OS. Whether I'm managing a server or troubleshooting a misconfigured service, this is the toolkit that makes that possible.

Quick Reference: System Operations Cheat Sheet

When you're in the terminal, speed is key. Here are the core commands I used today:

Text Editing

  • nano — Quick, intuitive text editing.
  • vim — Advanced, modal text manipulation.

File Transfers

  • wget — Download files directly from the web.
  • scp — Secure copy between systems.
  • python3 -m http.server — Instantly host files locally.

Process Management

  • ps aux — List every process currently running.
  • top — Real-time system performance monitor.
  • kill — Stop a specific process.
  • systemctl — Manage services (start, stop, restart, status).

Automation & Software

  • crontab -e — Schedule tasks (Format: MIN HOUR DOM MON DOW CMD).
  • apt update — Refresh your software repositories.
  • apt install — Install new tools securely.

Day 2 is done. The learning curve is steep, but the view from here is worth it. See you at Day 3!