LEARN LINUX THE RIGHT WAY

WHAT IS LINUX?

• Concept of a kernel
  • Hardware <-> Kernel <-> Software
  • Monolithic kernel vs Microkernel
• Open source nature
  • Worldwide development
  • You can contribute to it

WHAT IS A LINUX DISTRIBUTION

• OS based on monolithic Linux kernel

WHAT MAKES A LINUX DISTRIBUTION

• Core: libc; Base: coreutils; Extras;
  • Most Linux distros differ on Extras

DIFFERENCE BETWEEN LINUX DISTROS

• User-friendly vs user-centric distros
• Rolling release vs fixed release
  • Linux Mint vs Arch
• Binary vs Source based

INSTALLING SOFTWARE ON A LINUX DISTRO

• A linux distro distributes packages
• Package manager: apt, pacman
  • ´apt install firefox´
  • ´pacman -S firefox´

FLEXIBILITY OF LINUX

• Used on super computers
  • 100% of top 500
• Used on the server
  • 96% of top 1,000,000
• Used on personal computers

INTRODUCTION TO THE TERMINAL

• Commands are programs
  • ls, cd, cat, pwd, whoami, echo, ps
  • Learn every command: ´man command´
• Everything is a file
  • Programs, devices and drivers are files
  • ´ls /dev´, ´ls /bin´

AUTOMATION AND SCRIPTING

• Bash scripts
  • Shell vs Terminal
  • Variables: PATH, export, env
  • ´#!/bin/bash´ vs ´#!/bin/sh´
• Version control system (VCS)
  • Git: pull, push, commit, branch, log, status

HARDWARE AND SYSTEM CONFIGURATION

• Configure and verify network connection
  • ping, ip, nmtui, nmcli
• Boot process
  • Bootloader: grub
  • Boot modules and files: mkinitrd, dracut, initramfs, vmlinuz, grub-mkconfig
• Install, configure and monitor kernel modules
  • dmesg, lsmod, modprobe
• Manage storage
  • Partitions: GPT, MBR
  • Linux file system hierarchy: ´ls /´
  • File system types: ext4, btrfs, xfs
• Virtualization
  • Type 1 vs type 2 hypervisor
  • KVM: Kernel virtual machine

OPERATION AND MAINTENANCE

• Install, update and remove software
  • Package managers: apt, dnf, pacman
  • Build tools: Makefile and compiling
• Manage user and groups
  • Create: useradd, groupadd
  • Modify: usermod, groupmod, passwd
• Create, modify and redirect files
  • Text editors: vim, nano
  • Read files: cat, grep, less
  • File operations: touch, mv, cp, rm, ln
• Manage services (systemd)
  • Using systemctl: start, stop, enable, status, restart
• Linux graphical user interface
  • Servers: Xorg, Wayland
  • DE/GUI: Gnome, KDE, xfce, Cinnamon
  • Remote desktop: VNC, XRDP, Spice

LINUX SECURITY

• User/group permissions
  • ´ls -l´, chmod, chown, chgrp, rwx
• Athentication methods
  • SSH: Public and Private keys
• Firewall
  • UFW: Uncomplicated firewall
• Compress files
  • Compression: gzip, xz, bzip2
  • Integrety checks: MD5, SHA

TROUBLESHOOTING AND DIAGNOSTICS

• Analyse system properties
  • Network: ping, nmap, netstat, tcpdump, wireshark, traceroute, arp, ip, nmcli
  • Storage: iostat, df, du
  • CPU: uptime, lscpu
  • Memory: free, swap
• Analyse system processes
  • ps, time, pgrep, pkill
• Troubleshooting user issues
  • Permissions and authentication
• Application and hardware issues
  • Storage, firewall, permission, dependencies

Related

• Linux Audio Guide: Audio as specific Linux subsystem
• Disable Suspend on Linux: Power management as Linux skill
• Linux Power Management: Comprehensive power management