10 interview questions I would ask as a Senior DevOps engineer

In the rapidly evolving landscape of development, DevOps has emerged as a critical discipline that bridges the gap between development and operations, enabling organizations to deliver high-quality software at an accelerated pace.

As the demand for skilled DevOps engineers continues to rise, businesses increasingly rely on comprehensive interview processes to identify candidates with the necessary expertise and experience to excel in senior DevOps roles.

Interview questions a Senior DevOps engineer would ask in an interview

Interviewing is a critical part of the hiring process, but it's often overlooked. The wrong questions can quickly push an applicant away and make you look unprofessional.

To gain valuable insights into the interview process for a Senior DevOps engineer, we interviewed Anmol Nagpal, an accomplished DevOps engineer with extensive experience in the industry. Drawing upon his expertise and deep understanding of the field, we have compiled a list of ten crucial DevOps interview questions that effectively evaluate a candidate's proficiency, problem-solving abilities, and strategic mindset. Here are some key questions and their purpose Anmol suggests will help you hire a suitable DevOps engineer candidate:

What are the six things you consider when designing any architecture in the cloud?

Purpose: These are the basic principles every DevOps engineer should know. The six essential pillars are:

• Operational excellence
• Security
• Reliability
• Performance efficiency
• Cost optimization
• Sustainability

These days, many companies are moving to serverless; what's your opinion on that?

Purpose: Companies are moving to serverless, but they don’t know if this will be helpful or become a bottleneck for them, which explains this question. DevOps engineers will represent their experience in serverless, and while answering this question, a candidate will represent their experience and what he learned while working on serverless architectures.

If you choose any IaCs (Infrastructure as Code), which one will you choose and why?

Purpose: Currently, in the market, there are many tools that DevOps engineers use to provision infrastructure which include Terraform, Terragrunt, CDK, Pulumi, Cloud Formation & Bicep.

They should know why they choose those tools and what benefits the company will get when using them.

What should a DevOps engineer consider while designing any CI/CD pipeline?

Purpose: There are several ways to do this. However, DevOps engineers should know how designing the CI/CD will benefit the developers and the overall deployment life cycle. This should be reliable and fast and take little time to run and deliver code to production. It should also fail as early as possible to save time instead of waiting for the whole pipeline to run.

What’s your thought on running stateful applications on Kubernetes? Are managing databases on Kubernetes over virtual machines more straightforward?

Purpose: This is a fundamental question for DevOps.

“Shockingly, people say it's easy to run such apps in Kubernetes, but only a few come up with the best practices, including high availability, backups, and disaster recovery. ”

Anmol Nagpal

There should also be a proper plan while upgrading the cluster; for example, several people use MongoDB Custer in K8s but need to remember backups monitoring, logging, etc., The trick to remember is when we use MongoDB Cloud, it will come at a higher price initially but more reliable and cost-effective in the long run.

98% of security breach happens due to internal mistakes. What is your thought on this, and how will you prevent such incidents as DevOps?

Purpose: As DevOps, we are the guardians of infrastructure – not the Galaxy. But while guarding, we must ensure that we don’t randomly do the things that developers ask. We should talk to them and develop reliable and more secure solutions than simply following orders without asking questions for additional information.

Clients have sensitive data, i.e., SIN (social security) numbers, stored in DB, which are critical, and no developers should have access to it other than the Senior/team lead. What kind of security will you put in place to ensure that no one can access this data and that we have proper logging?

Purpose:

"One minor data breach could make an entire company go bankrupt. To avoid this, DevOps and developers must work together to ensure the data is secure, even if something like this happens."

Anmol Nagpal

Anmol added that DevOps should have alerts and logs to help them establish how the code is accessed and ultimately find the culprit.

What will your architecture be if the client is looking for a multi-region, where DB also needs to be multi-region on AWS Cloud?

Purpose: A DevOps engineer needs to spend more time reading blogs or have any experience with this, or else they will find this question difficult to answer. However, this will help clients decide whether to engage the candidate and keep them up to date with the latest news in the DevOps world.

In a Kubernetes setup, what are the top things you will ensure are fulfilled before going live on that cluster?

Purpose: Many DevOps engineers work on Kubernetes but don’t understand what must be done to ensure that the application will be highly available cost-effectively. This is the best way to test their knowledge.

"As DevOps, we must always have full scalability and not do everything manually – everything should be automated. This allows the person to relax between strenuous work without worrying about a high load on the website. An experienced DevOps engineer will know this."

Anmol Nagpal

There are many monitoring/logging/alerting tools in the market, both open-source and paid; which one will you choose and why?

Purpose: Answering this question can be pretty easy and, at the same time, quite challenging. I prefer working on open-source tools, but not all clients seek this. They mainly search for a reliable solution where they don’t have to depend on DevOps and the tools required for less maintenance. Clients are also more concerned with cost-effective solutions. A great candidate will answer what works best while prioritizing the client’s needs.

Do you think APM (application performance metrics) is a must-have in an engagement, whether small-scale or enterprise lever?

Though this question is primarily for developers, a great DevOps engineer will know about this. I mostly hear, “It’s related to infra. The code is faster on my local and other environments”, which is not the right reason, Anmol says.

“Debugging without APM is difficult. We might experience traffic or the application not performing well due to a bad query writer, where AMP plays a vital role. Using APM gives us the root cause of the problem.”

Anmol Nagpal

Why is DevOps popular in business?

"DevOps" is a buzzword that pops up in different contexts. Some describe it as a culture of collaboration and transparency, while others use it to describe the practice of automating software development and deployment processes.

DevOps is as popular as ever, and companies realize its importance in business processes. It's a new way of working that brings together developers and operations teams to work together on an engagement from start to finish. It provides teams with an efficient way of managing engagements, increasing speed, and reducing risks.

More importantly, It's about getting closer to your customers with faster releases and more frequent feedback cycles.

Regardless of how you use the term, it's essential to keep your eye on what people mean when they use it. And when you're interviewing candidates for a role in your organization, understanding how they view DevOps can help guide you during the interview process.

The importance of conducting effective interviews to assess candidates' suitability

Conducting effective interviews is crucial to identify candidates with the necessary technical skills, experience, and mindset to excel in the role. Here are a few more reasons why interviews are critical:

• A well-structured interview helps assess the candidate's problem-solving skills, decision-making capabilities, and capacity to handle high-pressure situations, which are common in DevOps environments.

• The job market is competitive, and many candidates want to get into DevOps engineer positions. So, interviewers must ask relevant questions about the candidate's skills and experience to ensure they are suitable for the role.

• The interview process helps you get a feel for the person, the team, and what they are looking for in a candidate. The more you know about the candidate, the better job you'll be able to do at finding a good fit.

• You might also find out some things you don't want to hire them for, which will help you avoid wasting your time and money on engaging someone who doesn't fit into your department or business.

• By conducting thorough interviews, your organization can minimize the risk of hiring mismatches and ensure you onboard individuals who can contribute to the company's growth and success.

Interview questions are rarely standardized, and this is especially true for technical roles. There are many different ways to approach an interview, but one of the most important things you can do is tailor your questions to your company's needs.

As the demand for Senior DevOps engineers continues to surge, finding the right candidate with the right skills and mindset can significantly impact your business’ success. With the insights gained from this collaboration, we hope to empower both interviewers and interviewees in their quest to navigate the complexities of hiring and securing senior roles in the vibrant world of DevOps.