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 contentscd
- Change directorypwd
- Print working directoryfind
- Search for files and directorieslocate
- Find files using a databasewhich
- Locate a command
File Operations
cp
- Copy files and directoriesmv
- Move/rename files and directoriesrm
- Remove files and directoriesmkdir
- Create directoriesrmdir
- 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 connectivitytraceroute
- Trace network pathnetstat
- Display network connectionsss
- Modern socket statisticscurl
andwget
- Download and test HTTP endpoints