When it comes to DevOps interviews, your knowledge of Linux commands and concepts plays a huge role in demonstrating your technical foundation. Whether you’re managing servers, debugging pipelines, or automating deployments, Linux is at the heart of every DevOps environment.

This blog will guide you through the most commonly asked Linux interview questions for DevOps engineers, along with explanations and examples. You’ll also learn how to approach command-line troubleshooting and scripting tasks—skills that interviewers frequently test in real-world DevOps scenarios.

Why Linux Knowledge Is Essential for DevOps Engineers

Linux is the backbone of cloud servers, CI/CD systems, and container environments like Docker and Kubernetes. Almost every DevOps tool—Jenkins, Ansible, Terraform, or Prometheus—runs smoothly on Linux.

In an interview, recruiters expect you to be comfortable working in the Linux command line, managing files, analyzing system performance, and automating tasks using shell scripts.

If you can confidently use Linux commands and explain the reasoning behind them, it reflects your real-world DevOps readiness.

Frequently Asked Linux Commands in DevOps Interviews

  1. File and Directory Management

These are the building blocks of Linux knowledge. Interviewers often ask you to perform basic navigation and file-handling tasks.

Common commands:

  • ls – List directory contents.
  • cd – Change directory.
  • pwd – Print working directory.
  • cp – Copy files or directories.
  • mv – Move or rename files.
  • rm – Remove files or directories.
  • mkdir – Create new directories.
  • rmdir – Delete empty directories.

Example question:
 How would you copy a directory recursively and preserve file permissions?
 Answer: cp -rp source_dir destination_dir

  1. File Viewing and Editing

You’ll often be asked to view and manipulate files directly from the terminal, especially when dealing with configuration or log files.

Commands to know:

  • cat – Display file contents.
  • more and less – Scroll through long files.
  • head and tail – Show the beginning or end of files.
  • grep – Search text patterns.
  • awk and sed – Process and modify text data.
  • vim or nano – Edit configuration files interactively.

Example question:
 How do you view the last 50 lines of a log file in real-time?
 Answer: tail -n 50 -f /var/log/syslog

  1. Permissions and Ownership

Understanding file permissions and ownership is vital for troubleshooting access or security issues.

Important commands:

  • chmod – Change file permissions.
  • chown – Change file owner and group.
  • umask – Set default file creation permissions.

Example question:
 How do you give execute permission to a file for all users?
 Answer: chmod a+x filename.sh

  1. Process and System Monitoring

A DevOps engineer must know how to monitor and manage running processes, especially when debugging performance issues.

Common commands:

  • ps – View running processes.
  • top or htop – Real-time system monitoring.
  • kill or killall – Terminate processes.
  • df -h – Check disk space usage.
  • du -sh – Check directory size.
  • free -m – Display memory usage.
  • uptime – Show system load and uptime.

Example question:
 How do you find and kill a process by name?
 Answer:
 ps aux | grep process_name
 kill -9 <PID>

  1. Networking Commands

Network troubleshooting is a common Linux for DevOps engineers topic. You’ll often need to verify connections, test ports, or debug DNS issues.

Key commands:

  • ping – Check connectivity.
  • curl – Make HTTP requests.
  • netstat or ss – View network connections.
  • ifconfig or ip addr – Show network interfaces.
  • nslookup or dig – Test DNS resolution.
  • telnet or nc – Test port connectivity.

Example question:
 How can you check if port 8080 is listening?
 Answer: netstat -tuln | grep 8080

  1. Package Management

Knowing how to install, update, and remove packages is essential for managing servers and setting up DevOps tools.

Examples:

  • Debian/Ubuntu: apt-get install, apt update, apt remove
  • RHEL/CentOS: yum install, yum update, yum erase

Example question:
 How do you check which version of a package is installed?
 Answer:
 apt list –installed | grep package_name or rpm -qa | grep package_name

  1. Disk and File System Management

System health often depends on disk space and file system performance.

Useful commands:

  • mount and umount – Mount or unmount file systems.
  • df -Th – Show disk usage and file system type.
  • lsblk – List block devices.
  • fdisk -l – View disk partitions.

Example question:
 How do you identify which partition is full?
 Answer: df -h

  1. Shell and Scripting Questions

Almost every DevOps interview includes shell and scripting questions. Employers want to see if you can automate tasks using Bash.

Common scripting questions:

  • Write a script to check if a service is running.
  • Write a script to monitor disk space.
  • How to pass arguments in a shell script.
  • Use of loops, conditions, and variables in Bash.

Example question:
 How do you find the number of lines in a file using Bash?
 Answer: wc -l filename.txt

  1. System and User Management

As a DevOps engineer, you must know how to manage users and services.

Important commands:

  • useradd, usermod, passwd, deluser – User management.
  • systemctl or service – Start, stop, or restart services.
  • whoami and id – Display user identity.

Example question:
 How do you check if a service is active?
 Answer: systemctl status nginx

  1. Log Analysis and Troubleshooting

Logs are crucial for identifying errors in CI/CD pipelines, deployments, and server processes.

Commands for log analysis:

  • tail -f /var/log/syslog – Monitor live logs.
  • grep “error” /var/log/messages – Filter error logs.
  • journalctl -u service_name – Check logs for specific services.

Example question:
 How do you find all failed login attempts?
 Answer: grep “Failed password” /var/log/auth.log

Tips for Preparing Linux Interview Questions

  • Practice using Linux daily—set up a test VM or use WSL (Windows Subsystem for Linux).
  • Understand the concepts behind each command, not just syntax.
  • Combine commands using pipes (|) and redirection (>, >>, <).
  • Learn to automate tasks using small Bash scripts.
  • Stay comfortable navigating and troubleshooting from the command line.

Conclusion

Mastering Linux commands and concepts is one of the best ways to stand out in a DevOps interview. Recruiters value candidates who can work confidently in a Linux environment, automate tasks through scripts, and troubleshoot real-time issues efficiently.

If you focus on hands-on practice and understanding how these commands apply to CI/CD pipelines, deployments, and automation, you’ll have a strong advantage in any DevOps interview.