Linux
Master Linux — the foundation of cloud infrastructure, DevOps, and modern computing. Over 96% of the world's top servers run Linux.
Documentation
| Guide | Description |
|---|---|
| Linux Fundamentals | File system, shell, permissions, processes, packages, text processing |
| System Administration | Disk management, services, cron, logging, performance, SSH, backups |
| Networking | Interfaces, routing, DNS, firewalls, SSH tunneling, network services |
| Security | Firewall, SELinux/AppArmor, SSH hardening, audit, kernel hardening |
| Command Cheat Sheet | 200+ commands organized by category — files, processes, networking, text |
| Interview Questions | 50+ questions from beginner to advanced with detailed answers |
Why Linux?
Linux is the operating system of choice for cloud, DevOps, and infrastructure because of its stability, security, flexibility, and open-source nature. If you're working in tech, Linux skills are essential.
Learning Path
- Start with fundamentals — file system, shell, permissions, processes
- Learn system administration — services, disk management, logging, SSH
- Master networking — interfaces, routing, DNS, firewalls
- Harden security — firewall, SELinux, SSH hardening, auditing
- Keep the cheat sheet handy — 200+ commands at your fingertips
Quick Start
# System info
uname -a
hostnamectl
# Navigate and explore
ls -la /
cd /var/log && ls -lh
# User and permissions
whoami
id
sudo useradd -m newuser
# Processes
ps aux | head -20
top -bn1 | head -15
# Networking
ip addr show
ss -tulnp
# Package management (Ubuntu/Debian)
sudo apt update && sudo apt upgrade -y
External Resources
| Resource | Description |
|---|---|
| Linux Journey | Interactive guides with exercises and quizzes |
| Linux Survival | Interactive browser-based tutorial |
| The Linux Command Line | Free book by William Shotts |
| Linux From Scratch | Build your own Linux from source |
| NixCraft | Practical system administration guides |
| learnlinux.tv | Practical video tutorials |
| Linux SysOps Handbook | System admin study notes |
| OSTEP | Operating Systems: Three Easy Pieces |
Video Tutorials
| Resource | Description |
|---|---|
| The Complete Linux Course | Beginner to power user (7+ hours) |
| Linux for Hackers | NetworkChuck Linux series |
| Tecmint Linux Guide | Written articles and lessons |
Books
| Title | Author | Type |
|---|---|---|
| The Linux Command Line | William Shotts | Free |
| Linux Bible | Christopher Negus | Paid |
| How Linux Works | Brian Ward | Paid |