Interview questions to ask while hiring a DevOps engineer

In the rapidly evolving tech landscape, the role of DevOps Engineers has become crucial, with job postings increasing by 54% over the past year alone. As businesses strive for continuous integration and delivery, hiring the right DevOps talent is essential. For HR professionals and CXOs, understanding the key competencies and cultural fit necessary for this role is paramount. Practical interview questions can reveal technical prowess and the ability to thrive in a collaborative, fast-paced environment. This blog explores essential interview questions to help you identify top DevOps candidates, ensuring your organization remains agile and competitive in today’s market.

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Why use skills assessments for assessing DevOps Engineer candidates?

Skills evaluations must be used during the evaluation process to ensure that DevOps Engineer candidates possess the technical expertise and problem-solving skills necessary for the position. The hiring process is more balanced when using skills exams that offer objective data. Platforms like Testlify provide comprehensive assessments that evaluate a candidate’s coding skills and knowledge of various DevOps tools and practices. By incorporating these assessments into your hiring strategy, you can better identify top talent, ensuring that candidates meet technical requirements and fit well within your team’s workflow. This approach leads to more informed hiring decisions, strengthening DevOps capabilities and organizational success.

When should you ask these questions in the hiring process? 

When hiring a DevOps Engineer, inviting applicants to complete a DevOps skills assessment is ideal. This initial step helps filter out candidates lacking the necessary technical skills, ensuring that only qualified individuals proceed to the interview stage. Skills assessments objectively measure a candidate’s abilities in areas such as coding, system management, and automation, making the subsequent interview process more focused and efficient.

Once candidates pass the skills assessment, you can use a few of the below-targeted interview questions to evaluate their problem-solving abilities, cultural fit, and real-world experience. This two-step process ensures that you verify technical competencies and gain insights into how candidates approach complex challenges, collaborate with team members, and contribute to your organization’s DevOps practices. By integrating skills assessments and structured interview questions, you enhance your hiring strategy and increase the likelihood of finding the right DevOps Engineer for your team.

Check out Testlify’s: DevOps Engineer Test

25 general DevOps engineer interview questions to ask applicants

Conducting technical interviews for DevOps Engineer candidates requires a thorough understanding of theoretical concepts and practical applications. To help you assess the expertise and readiness of your potential hires, we have compiled a list of 25 essential technical interview questions. These questions cover various topics, from CI/CD and container management to cloud services and security practices.

1. What is your approach to patch management in a Linux environment?

Look for: Attention to security implications and the ability to manage dependencies effectively.

What to Expect: Expect a description of systematic approaches using tools like YUM or APT, testing patches in a staging environment, and coordinating with security policies.

2. Can you explain the process of writing a shell script to monitor system performance?

Look for: Practical knowledge of shell commands and automation of routine tasks.

What to Expect: Candidates should detail the specific metrics they would monitor (e.g., CPU usage, memory consumption), the commands they would use (vmstat, top, etc.), and how they would automate alerts.

3. Describe a challenging configuration management task you handled. What tools did you use?

Look for: Depth of understanding of configuration management principles and problem-solving skills.

What to Expect: Description of using tools like Ansible, Puppet, or Chef, with specifics on the playbook or recipes used, and how they ensured idempotence and compliance with policy.

4. How do you manage version control for a large team using Git?

Look for: Understanding of collaborative approaches in version control and adherence to best practices.

What to Expect: Strategies like branching and merging, use of pull requests for review, and possibly Git hooks for automation. Mention of best practices for commit messages and maintaining a clean history is a plus.

5. Explain the concept of containerization and its benefits in DevOps practices.

Look for: Clear understanding of containers’ role in ensuring consistency across environments from development to production.

What to Expect: Mention of Docker or similar technologies, explanation of container isolation, lightweight nature compared to VMs, and benefits for CI/CD pipelines.

6. How would you deploy a scalable and secure web application using Terraform?

Look for: Ability to design repeatable and predictable infrastructure deployments, with a focus on scalability and security.

What to Expect: Discussion should include defining infrastructure as code, using modules, planning changes with terraform plan, and applying them with terraform apply. Security aspects might include managing secrets and using service roles.

7. What experience do you have with cloud services like AWS or Azure? Describe how you have used them in your projects.

Look for: Practical application of cloud services and understanding of cost-efficiency and scalability.

What to Expect: Specific services used (e.g., EC2, S3, Azure VMs, Blob Storage), scenarios such as data storage, compute instances for application deployment, and use of managed services.

8. Can you describe your workflow for ensuring continuous integration and deployment?

Look for: Emphasis on automation, reducing errors, and speeding up deployment cycles.

What to Expect: Mention of CI/CD tools (e.g., Jenkins, GitLab CI, CircleCI), automating builds, tests, and deployments, and perhaps integrating code quality checks.

9. How do you handle monitoring and logging in a distributed system?

Look for: Ability to set up comprehensive monitoring that aids in proactive troubleshooting and analysis.

What to Expect: Discussion of tools like Prometheus, Grafana, ELK Stack, or Splunk; strategies for log aggregation, analysis, and real-time monitoring.

10. What strategies do you use for database management in a DevOps environment?

Look for: Understanding of database continuity, integrity, and security within a CI/CD context.

What to Expect: Use of migration scripts, database version control, backups, and replication strategies. Integration of database operations into deployment pipelines is a plus.

11. Describe how you ensure security and compliance when configuring servers.

Look for: Depth of understanding of security best practices and compliance requirements.

What to Expect: Use of configuration management tools with security-focused modules (e.g., Ansible with roles for security), regular audits, and adherence to compliance frameworks.

12. How do you manage dependencies in a microservices architecture?

Look for: Approaches to maintain service independence while ensuring smooth interaction across services.

What to Expect: Explanation of using container orchestration platforms (e.g., Kubernetes), service meshes, and continuous testing to manage service dependencies.

13. What is your method for rolling back a deployment in a CI/CD pipeline?

Look for: Strategies that emphasize minimal downtime and rapid recovery from errors.

What to Expect: Description of using blue-green deployments, canary releases, or feature toggles to minimize disruption, and automated rollback mechanisms.

14. Explain how you use scripting to automate routine tasks.

Look for: Efficiency in script writing and ability to handle various automation scenarios.

What to Expect: Specific examples of tasks automated (e.g., backups, system updates) using bash, Python, or other scripting languages.

15. How do you ensure high availability and disaster recovery in cloud environments?

Look for: Comprehensive planning for fault tolerance and rapid recovery.

What to Expect: Discussion of multi-zone or multi-region deployments, use of load balancers, auto-scaling, and regular DR drills.

16. What tools and strategies do you use for network troubleshooting in a DevOps context?

Look for: Depth of network knowledge and proactive management practices.

What to Expect: Use of network monitoring tools, understanding of network protocols, and perhaps scripting for automated troubleshooting tasks.

17. Describe your experience with build tools like Maven or Gradle.

Look for: Ability to optimize build processes for speed and reliability.

What to Expect: Discussion on how they configure build scripts for automation, manage dependencies, and integrate with CI tools.

18. How do you manage secret keys and credentials in your infrastructure?

Look for: Security-first approach to managing sensitive information.

What to Expect: Use of vaults (e.g., HashiCorp Vault), environment variables, or encrypted storage solutions, with emphasis on access controls and auditing.

19. What is your approach to testing in a DevOps environment?

Look for: A thorough understanding of how continuous testing fits into DevOps practices.

What to Expect: Integration of automated testing in the CI/CD pipeline, use of different types of tests (unit, integration, system), and possibly TDD or BDD approaches.

20. Can you describe an incident where you had to troubleshoot a critical production issue?

Look for: Problem-solving skills under pressure and ability to mitigate issues without significant downtime.

What to Expect: A structured approach to incident management, use of monitoring tools to diagnose issues, and communication with stakeholders.

21. How do you handle configuration drift in multiple environments?

Look for: Strategies that ensure environmental parity and reduce operational risks.

What to Expect: Use of infrastructure as code to maintain consistency, regular audits, and automated reconciliation processes.

22. Explain how you would set up a secure bridge between private data centers and public clouds.

Look for: Understanding of hybrid cloud challenges and security.

What to Expect: Use of VPNs, dedicated connectivity services like AWS Direct Connect or Azure ExpressRoute, and strong encryption practices.

23. How do you optimize resource usage in a virtualized environment?

Look for: Efficiency in resource management and ability to enhance performance while controlling costs.

What to Expect: Methods like resource reservation, prioritization, and use of performance monitoring tools to adjust allocations.

24. Describe your process for updating an application without downtime.

Look for: Focus on user experience and minimizing service interruption.

What to Expect: Techniques such as rolling updates, use of load balancers, and session persistence configurations.

25. What methodologies do you follow to ensure team collaboration in DevOps practices?

Look for: Ability to foster a collaborative environment and integrate operations seamlessly with development.

What to Expect: Implementation of Agile, Scrum, or Kanban methodologies, regular stand-ups, and emphasis on communication tools and documentation.

Check out Testlify’s: DevOps Engineers Hiring Guide

5 code-based DevOps engineer interview questions to ask applicants

Assessing a DevOps Engineer’s coding skills is crucial for evaluating their ability to automate, manage infrastructure, and troubleshoot. Here are five concise code-based interview questions designed to test their proficiency in scripting, containerization, database querying, and configuration management. Each question is brief, taking only 5–7 minutes to complete, making them ideal for real-time coding assessments. These questions will help you gauge the candidate’s practical skills and problem-solving approach in essential DevOps tasks.

1. Write a Bash script to find and list all .log files in the /var/log directory.

Look for: Familiarity with the Bash environment, understanding of file system operations, and correct use of the find command.

#!/bin/bash
find /var/log -type f -name "*.log"

2. Write an Ansible playbook snippet to install nginx on a Ubuntu server.

Look for: Knowledge of Ansible syntax, module use (e.g., apt for Ubuntu), and basic playbook structure.

---
- hosts: all
  become: yes
  tasks:
  - name: Install nginx
    apt:
      name: nginx
      state: present

3. Write a Dockerfile snippet to create a basic image that starts from ubuntu:20.04, installs curl, and runs a bash shell.

Look for: Understanding of Dockerfile directives (FROM, RUN, CMD), containerization concepts, and familiarity with Linux package management.

FROM ubuntu:20.04
RUN apt-get update && apt-get install -y curl
CMD ["/bin/bash"]

4. Write a simple Git command sequence to create a new branch and switch to it.

Look for: Familiarity with version control using Git, specifically branch management.

 git checkout -b new-feature-branch

5. Provide a Terraform snippet to create a basic AWS EC2  instance with a tag.

Look for: Knowledge of Terraform syntax and a basic understanding of AWS resources. Familiarity with infrastructure as code principles.

resource "aws_instance" "example" {
  ami           = "ami-0c55b159cbfafe1f0"
  instance_type = "t2.micro"
  tags = {
    Name = "MyInstance"
  }
}

5 Interview questions to gauge a candidate’s experience level

1. Can you describe a time when you had to collaborate with a cross-functional team to solve a critical issue? How did you handle communication and coordination?

2. Tell me about a challenging project you worked on. What was your role, and how did you overcome the obstacles?

3. How do you prioritize tasks when managing multiple projects or deadlines? Can you give an example of how you have effectively managed your time?

4. Describe a situation where you had to change your DevOps processes significantly. How did you manage the transition and ensure team buy-in?

5. How do you stay current with new DevOps tools and technologies? Can you share an example of how you’ve applied new knowledge to improve your work?

Key takeaways

Hiring the right DevOps Engineer is crucial for enhancing operational efficiency and fostering innovation. Given the increasing demand for skilled DevOps professionals, employing a comprehensive hiring strategy that includes technical and soft skills assessments is essential. Start with a skills assessment to ensure candidates have the necessary technical competencies in CI/CD, container management, and cloud services. Follow this with targeted interview questions to evaluate their problem-solving abilities, past experiences, and cultural fit.

Additionally, assessing soft skills and working styles is equally important. Questions about collaboration, time management, and adapting to new tools can provide insights into a candidate’s ability to thrive in a dynamic environment. By integrating these strategies, HR professionals and CXOs can make informed decisions, ensuring they hire DevOps Engineers with the technical expertise, interpersonal skills, and adaptability to drive the organization’s success.