Top 50 Linux interview questions to ask candidates

Linux is an open-source operating system that was launched in 1991 by Linus Torvalds. The operating system provides an alternative to proprietary operating systems, like iOS, Windows, or MacOS. One of the best features of Linux is that it is free to use and share, and its source code is open for anyone to explore and even modify. This encourages all users to work together towards continuously improving the Linux operating system. Since its launch, the system has changed significantly, and today, it is a stable, safe, efficient, and cost-effective system with a robust support community.

Open source:

The source code of Linux is available freely, and all users are allowed to modify and distribute it based on their requirements. This promotes innovation, security, and transparency.

Reliability:

Linux is a stable and highly reliable operating system and a popular choice for personal as well as enterprise use. The system can also run for long durations without needing a reboot, which also makes it a widely used operating system for servers and critical systems.

Flexibility:

Linux also comes with a high degree of flexibility. It can be used in a range of environments, including desktops, smartphones, supercomputers, software packages, and system configurations, allowing users to tailor the Linux experience according to their requirements.

Security:

The collaborative nature of the open-source community and the design principles of Linux have made the system inherently secure, as users have the ability to audit the source code and fix bugs rapidly.

Vast ecosystem:

With Linux, users get a rich ecosystem of diverse applications, including several popular software frameworks and tools, like Python, GNU tools, Apache web server, etc.

In an organization, Linux developers are responsible for the installation and maintenance of a Linux-based operating system(s) and the correct working of the hardware and equipment of the organization’s functions. Linux developers also oversee server installation and the transition of the organization’s hardware to Linux from other operating systems.

Some of the typical qualifications that a candidate should possess for getting selected as a Linux developer include a Bachelor’s or Graduate degree in computer science or computer engineering, deep understanding of the Linux operating system, knowledge of computing and scripting, familiarity with agile practices, ability to work with cloud systems, and fluency in various software, systems, and programming languages.

Integrating Linux interview questions into the hiring campaign helps recruiters identify the best talent for open Linux developer positions. Linux interview questions and answers can be used to assess the technical knowledge, behavioral traits, and cognitive abilities of candidates. The questions can be designed to help recruiters screen highly skilled candidates from candidates who only have basic knowledge of the operating system. The right Linux interview questions also provide candidates with the opportunity they need to demonstrate their understanding of Linux and their ability to apply their knowledge to solve real-world problems. They can provide insight into how candidates think and act in specific situations. Additionally, using Linux interview questions can also help mitigate unconscious bias in the hiring process.

1. How to differentiate between Linux and Unix?
2. Define Linux Kernel
3. What are the basic features of the Linux OS?
4. Which are the most common Linux Distros?
5. How is Linux different from Windows?
6. Explain the types of file permissions in Linux
7. What is a root account?
8. What are CLI and GUI in Linux?
9. Define swap space
10. How to differentiate between soft links and hard links?
11. How is a symbolic link created in Linux?
12. What are standard streams?
13. What are the basic components of Linux?
14. How to edit the Linux Kernel?
15. Explain LILO in Linux
16. List some pros and cons of an open-source system.
17. Differentiate between DOS and BASH
18. How is the command prompt opened while issuing a command?
19. Explain inode and process ID
20. What types of modes are used in a vi editor?

1. How to mount or unmount filesystems in Linux?
2. How does one troubleshoot any network connectivity issues in Linux?
3. How can all running processes be listed in Linux?
4. Define the chmod command in Linux and explain how it is used
5. What commands can be used to check disk space usage?
6. Explain how to find the PID of a running process
7. Explain the rsync command and its use for synchronization
8. How can a disk be formatted in Linux?
9. What command can be used to change a user account’s password?
10. Differentiate between a thread and a process in Linux

1. How to search a directory and its subdirectories to find all the files that were modified in the last hour?
2. What does the cron command do, and how can it be used to schedule tasks?
3. How can all the empty directories in a specified path be recursively deleted?
4. How do the chmod+t and chmod+x commands differ from each other?
5. How can the priority of running processes be changed?
6. What is the purpose of the cut command in Linux?
7. Explain how the cut command can be used to extract particular volumes from a CSV file
8. What are shell scripts, and how are they used in Linux?
9. What command will return a list of all the open ports on Linux servers?
10. How to optimize the performance of a Linux server?
11. How to identify the ten largest files from a directory and its subdirectories?
12. What is the grep command, and how is it used?
13. Explain a daemon in Linux
14. What is the ps command?
15. Give an example of a situation where the ps command can be used in a real-world setting
16. Which fields does an inode store?
17. Define the proc file system
18. How to secure Linux servers?
19. How to administer a Linux server?
20. Explain the Linux virtual memory system

The right blend of advanced and basic interview questions for Linux developers is a suitable way to evaluate candidates, but it is crucial to remember that they should only be a part of a comprehensive pre-employment assessment process. Establishing a well-rounded approach for evaluating potential candidates for an open Linux developer position in the organization is essential for making an informed hiring decision. Using pre-employment assessments will help organizations identify top talent, understand candidates’ strengths and areas of improvement, and evaluate cultural fitment according to organizational needs.

Recruiters should consider using a range of online assessments, like domain-based tests, cognitive ability tests, behavioral assessments, soft skills assessments, etc., along with structured Linux interview questions and answers for a robust pre-employment assessment strategy.

While selecting relevant Linux interview questions to assess candidates, it is necessary to optimize and streamline the entire assessment process with the range of pre-employment assessment tests offered by Mercer | Mettl. Mercer | Mettl’s library of scientifically validated tests helps recruiters identify highly skilled candidates with the required Linux experience, who are also a good cultural fit for the organization. Hiring managers can establish a screening process based on multiple measures, including structured Linux assessment test from the Mercer | Mettl library to properly evaluate the hard skills, soft skills, cognitive abilities, behavioral traits, and personality of the candidates.