Linux Fundamentals

By bamr87

Basic Linux concepts including navigation, scripting, security, and networking

Estimated reading time: 1 minutes

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Linux Fundamentals

Introduction

This guide covers essential Linux concepts that every IT professional should know. Whether you’re just starting your journey or need a refresher, these fundamentals will help you navigate the Linux ecosystem effectively.

Navigation - File Exploration

Basic Commands

  • ls - List directory contents
  • cd - Change directory
  • pwd - Print working directory
  • find - Search for files and directories
  • locate - Find files using a database
  • which - Locate a command

File Operations

  • cp - Copy files and directories
  • mv - Move/rename files and directories
  • rm - Remove files and directories
  • mkdir - Create directories
  • rmdir - Remove empty directories

Scripting

Bash Scripting Basics

  • Variables and environment setup
  • Control structures (if/else, loops)
  • Functions and parameter handling
  • Input/output redirection
  • Error handling and debugging

Shell Automation

  • Cron jobs for scheduling
  • Service management with systemctl
  • Log analysis and monitoring
  • Backup and maintenance scripts

Security

File Permissions

  • Understanding rwx permissions
  • chmod and chown commands
  • User and group management
  • sudo configuration

System Security

  • SSH key management
  • Firewall configuration (iptables/ufw)
  • User authentication and authorization
  • Security updates and patching

Networking

Network Basics

  • TCP/IP fundamentals
  • Network configuration
  • DNS and hostname resolution
  • Port management and services

Network Tools

  • ping - Test connectivity
  • traceroute - Trace network path
  • netstat - Display network connections
  • ss - Modern socket statistics
  • curl and wget - Download and test HTTP endpoints

Resources