Linux is one of the most widely used open-source operating systems. It's fast, secure, stable, and powers everything from smartphones and servers to cloud platforms and IoT devices. Linux is especially popular among developers, system administrators, and DevOps professionals.
- A Unix-like OS used in servers, cloud infrastructure, supercomputers, personal computers and embedded systems.
- Reliable and secure, making it ideal for web hosting, networking, and automation.
- Preferred in DevOps, where it's used for scripting, configuration, containerization (Docker), and CI/CD pipelines.
- Open-source and customizable, giving users full control over their systems and workflows.
Understanding Linux Basics
This section introduces what Linux is, how it works, and foundational concepts.
- Introduction
- Linux Distribution
- Choosing a Distribution
- Architecture of Linux
- Difference between Linux Vs Unix
Linux File System
Understand the structure, file types, paths, and navigation.
- Linux File System
- Linux File Hierarchy Structure
- Linux Directory Structure
- File System Navigation Commands
- Absolute and Relative Pathnames in UNIX
Linux Commands
Learn essential terminal commands used for navigation, file management, system monitoring, and basic operations.
File Management & Permissions in Linux
Detailed operations for working with files and directories.
- File Management
- File System Navigation Commands in Linux
- Directory Management in Linux
- Permissions in Linux
- Changing Permissions using chmod
- Changing Ownership using chown
Archiving and Compressing
- Creating and Extracting Archives using tar
- Compressing Files using gzip
- Decompressing Files using gunzip
- Compressing and Extracting Files using zip and unzip
- High-Compression Archiving using bzip2
- High-Efficiency Compression using xz
Package Management
Learn how software is installed, updated, and removed on different Linux distributions.
- Package Managers & systemctl
- apt-get Package Manager (Debian/Ubuntu)
- dpkg – Debian Package Manager
- dnf Package Manager (Fedora/RHEL 8+)
- yum Package Manager (CentOS/RHEL)
User and Group Management
Managing users and groups in Linux involves creating, modifying, and controlling user accounts, assigning permissions, and organizing users into groups for efficient access control and system security.
- User Management in Linux
- Creating Users using useradd
- Creating Users Interactively using adduser
- Deleting Users using userdel
- Managing User Passwords using passwd
- Viewing User Information using id
- Group Management in Linux
- Managing Groups in Linux
- Creating Groups using groupadd
- Deleting Groups using groupdel
- Checking User Group Membership
- Managing Administrative Access using sudo
Linux Networking
Configuring IP addresses and managing network interfaces to setting up firewalls, monitoring traffic, and enabling communication between devices and servers:
- Configuring Network Interfaces using ifconfig
- Managing IP Addresses and Interfaces using ip
- Managing Network Connections using nmcli
- Testing Network Connectivity using ping
- Monitoring Network Connections using netstat
- Inspecting Socket Statistics using ss
- Tracing Network Routes using traceroute
Networking Services
Linux Firewall
Monitoring & Troubleshooting
- Configure network interfaces in CentOS
- Network configuration and trouble shooting
- System Monitoring in Linux
Process Management
Learn how Linux creates, monitors, and controls running processes, including foreground, background, and system processes.
- Viewing Processes using ps Command
- Real-Time Process Monitoring using top
- Enhanced Process Monitoring using htop
- Managing Processes using kill Command
- Controlling Process Priority using nice
Managing Background and Foreground Jobs
- Running Jobs in Background using bg
- Bringing Jobs to Foreground using fg
- Monitoring Disk Usage using du
System Services & systemd
Understand how Linux services are managed and controlled using systemd, including the boot process, service lifecycle, and logging.
System Monitoring
Monitor system resources, performance, and running processes to ensure Linux system stability and efficiency.
- Checking Disk Space using df
- Monitoring Memory Usage using free
- Viewing CPU Information using lscpu
- Checking System Uptime and Load using uptime
- Monitoring CPU and I/O Performance using iostat
- Listing Open Files and Processes using lsof
Linux Practical Guides for System Administration
Hands-on guides for real-world Linux administration tasks.
- Enabling SSH in Ubuntu
- Installing JDK on Ubuntu
- Installing Atom Editor on Linux
- Installing Ubuntu on VMware in Windows
- SCP Command for Secure File and Folder Transfer
- Installing and Configuring Nginx from Source on Linux
Shell Scripting
Shell scripting is writing a series of commands in a script file to automate repetitive tasks.
- Introduction to Linux Shell
- Introduction to Kernel
- Different Shells in Linux
- Difference between Shell and Kernel
- Introduction to Terminal
Creating and Running Shell Scripts
- Creating a Shell Script
- Defining the Shell Script Interpreter (#!/bin/bash)
- Comments in the Shell Script
- Storing and Displaying Messages in a Shell Script
- Storing the Output of Commands
- Exit Codes of Shell Commands
Variables in Shell Scripting
Bash Scripting
- Bash Scripting – Introduction to Bash and Bash Scripting
- Bash Script – Define Bash Variables and Its Types
- Working of Bash Scripting
- Run Bash Script In Linux
- Bash Scripting - Functions
- Difference between Shell (sh) and Bash
- Basic Operators in Shell Scripting
Advanced Topics in Shell Scripting
Linux Cloud
- The Role of Linux in Cloud Computing and DevOps
- Linux commands in DevOps
- Deploying and Managing Linux in the Cloud
Linux Interview Questions
Here are the top 70 most commonly asked Linux interview questions, covering essential topics like commands, shell scripting, system administration, networking, and troubleshooting: