DevOps Engineer Interview Questions

What should you focus on for a DevOps interview?

CI/CD, Kubernetes, and production troubleshooting appeared more often in these DevOps interviews than across all interviews. Mid-level questions made up 49% of the questions. Start by checking whether you can explain how you would build, release, and run software, not just define the tools.

Can you explain a pipeline and your deployment choices?

Pipeline design and deployment strategy questions each appeared in 6 of 106 interviews. Try describing a pipeline from build to deployment. Then check whether you can explain the choices you made along the way.

• How do continuous integration, continuous delivery, and continuous deployment differ?
• How would you keep build artifacts reproducible?
• When would you choose rolling updates, blue-green, or canary deployments?
• What would you inspect when a release goes wrong?

Git branching and build tools are also covered. Can you explain how your branching approach fits your pipeline?

Can you explain containers, Kubernetes, and cloud infrastructure?

The Kubernetes questions cover basic concepts and cluster operations. Start with what Kubernetes is used for, then explain how you would manage changes to an application running in it.

• What do the control-plane components do?
• What roles do a ConfigMap and a Service play?
• How does Kubernetes handle rolling updates and rollbacks?
• How would you build a Docker image and configure container networking and volumes?

For cloud and Terraform, can you explain state and drift, then describe how you would provision infrastructure? For security, can you explain how you would manage permissions and secrets, and harden containers?

Can you walk through a production investigation?

Monitoring questions cover metrics, logs, traces, dashboards, and alerts. Incident questions also cover diagnosis, coordination, and root cause analysis. Check whether you can describe what you would inspect, rather than only name a monitoring tool.

• How would you find what is consuming disk space on a Linux server?
• How would you use metrics, logs, and traces to investigate a problem?
• How would you coordinate an incident and investigate its root cause?

Should you prepare to write code?

Coding tasks appeared in 4 of 106 interviews. Use these tasks to check your scripting skills: can you write a process-status script that saves its result? Can you parse and validate a command's JSON output in Python or Bash, including unsuccessful exits, partial output, and malformed JSON?

What DevOps Engineer interviews cover

The 20 most asked DevOps Engineer questions

Counted by interview, not by mention: a question asked twice in one conversation counts once.

1. What is DevOps?

   Asked in 7 of 106 interviews · last asked Oct 7 · Concept · Junior

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   DevOps is a way of working that brings development and operations together to deliver software quickly and reliably. Teams share responsibility for building, deploying, and running software, using automation and feedback to improve it. DevSecOps makes security a shared responsibility throughout this work, rather than a final check.

   • DevOps combines teamwork, shared ownership, and technical practices; it is not just a set of tools.
   • Common practices include CI/CD, infrastructure as code, monitoring, and small, frequent changes.
   • DevSecOps includes security checks and fixes throughout development and operations.

   What the interviewer checks: The interviewer checks whether you understand DevOps as shared ownership and continuous improvement, not just automation.

   Other ways it was asked

   • “What is DevSecOps?”

2. How would you design a CI/CD pipeline?

   Asked in 6 of 106 interviews · last asked Oct 20 · Design · Mid-level

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   I would trigger the pipeline from Git changes, then run checks, tests, and security scans before building a versioned artifact. I would deploy the same artifact to staging, test it, then promote it to production, with approval if needed. I would add health checks and a tested rollback path. I would use GitHub Actions or GitLab CI to coordinate these stages.

   • Keep pipeline definitions in Git so changes can be reviewed and tested.
   • Build once and promote the same artifact across environments to avoid differences.
   • Store secrets securely and give pipeline jobs only the permissions they need.
   • Monitor deployments and plan database changes so older application versions can still work during rollback.

   What the interviewer checks: The interviewer is checking whether you can turn code changes into safe, repeatable releases and recover from failures.

   Other ways it was asked

   • “How do you build and maintain a CI/CD pipeline?”
   • “What stages would you include in a CI/CD pipeline for an application?”
   • “Can you briefly describe how a CI/CD pipeline works?”

3. What deployment strategies are available, and when would you choose rolling updates, blue-green, or canary deployments?

   Asked in 6 of 106 interviews · last asked Oct 1 · Concept · Mid-level

   Show answer

   Common strategies include recreate, rolling updates, blue-green, and canary. I choose rolling updates to replace instances gradually with limited extra capacity. I choose blue-green to switch traffic between two full environments and switch back quickly. I choose canary to test a release on a small share of live traffic before expanding it.

   • Rolling updates need readiness checks and enough healthy instances to serve traffic while old and new versions coexist.
   • Blue-green uses load balancer or router changes to switch traffic, but temporarily needs capacity for both environments.
   • Canary rollout can automatically stop and return traffic to the stable version when error or latency limits fail.
   • Keep database changes backward-compatible; switching application versions back does not undo data changes.

   What the interviewer checks: The interviewer checks whether you can balance deployment risk, capacity, traffic control, and safe rollback.

   Other ways it was asked

   • “Can you explain the different deployment strategies available in Kubernetes?”
   • “What deployment strategies are available in Kubernetes?”
   • “What do you know about the canary deployment approach, and what other deployment strategies do you know?”

4. What is Kubernetes, and what is it used for?

   Asked in 5 of 106 interviews · last asked Sep 4 · Concept · Junior

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   Kubernetes is an open-source platform for managing containerized applications across a group of machines. It automates deployment, scaling, and recovery when workloads fail. It also helps applications find each other, routes traffic to them, and supports controlled updates.

   • Runs containers in pods and schedules those pods onto worker nodes.
   • Keeps the running system close to the desired state you define.
   • Supports service discovery, load balancing, rolling updates, and automatic scaling when configured.
   • Adds operational complexity, so simpler tools may suit small applications.

   What the interviewer checks: The interviewer checks whether you understand container orchestration and the problems Kubernetes solves.

   Other ways it was asked

   • “What is Kubernetes, and have you worked with it?”
   • “What is Kubernetes?”
   • “What is Kubernetes, and why is it used?”

5. What is a ConfigMap in Kubernetes?

   Asked in 5 of 106 interviews · last asked Oct 7 · Concept · Junior

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   A ConfigMap is a Kubernetes object that stores non-sensitive configuration as key-value pairs. Pods can use its values as environment variables or mounted files, keeping configuration separate from the container image. Use a Secret for sensitive data, such as passwords, but remember that Secrets are not encrypted by default.

   • A Pod and the ConfigMap it references must be in the same namespace.
   • Changing a ConfigMap does not update environment variables in running containers; replace the Pods.
   • Mounted files update eventually, except with subPath mounts; the application must reload them.
   • Secrets support sensitive data, but need access controls and encryption at rest.

   What the interviewer checks: The interviewer checks whether you understand how Kubernetes separates application configuration from images and handles sensitive values.

   Other ways it was asked

   • “Explain what a ConfigMap is in Kubernetes.”
   • “What is a Kubernetes ConfigMap?”
   • “What is the difference between a Secret and a ConfigMap in Kubernetes?”

6. What is CI/CD, and how do continuous integration, continuous delivery, and continuous deployment differ?

   Asked in 4 of 106 interviews · last asked Oct 20 · Concept · Junior

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   CI/CD uses automation to build, test, and release software. Continuous integration means merging code changes often and checking them with automated builds and tests. Continuous delivery keeps tested changes ready for production, but release needs a human decision. Continuous deployment sends every change that passes the pipeline to production automatically.

   • CI/CD gives faster feedback and makes releases more repeatable.
   • Common stages include building, testing, packaging, and deploying.
   • GitHub Actions, GitLab CI/CD, and Jenkins are common pipeline tools.
   • Continuous deployment needs reliable automated checks, production monitoring, and a way to recover from failed releases.

   What the interviewer checks: The interviewer checks whether you understand automated validation and the release decision that separates delivery from deployment.

   Other ways it was asked

   • “What is CI/CD, and why is it important?”
   • “What is CI/CD, and what are its main stages and commonly used tools?”
   • “What is the difference between continuous integration (CI) and continuous delivery or deployment (CD)?”

7. What are the Kubernetes control-plane components?

   Asked in 4 of 106 interviews · last asked Sep 21 · Concept · Mid-level

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   The Kubernetes control plane manages the cluster and works to keep it in the desired state. Its main components are kube-apiserver, etcd, kube-scheduler, and kube-controller-manager. Cloud-based clusters may also use cloud-controller-manager to manage cloud resources, such as load balancers.

   • kube-apiserver handles API requests, checks access, validates changes, and reads or writes cluster state in etcd.
   • etcd is the key-value store that holds Kubernetes cluster data.
   • kube-scheduler selects nodes for unscheduled Pods based on resource needs and placement rules.
   • kube-controller-manager runs controllers that watch cluster state and act to match the desired state.

   What the interviewer checks: The interviewer checks whether you can name the main components and explain each component’s role.

   Other ways it was asked

   • “What is the Kubernetes control plane, and what are its components?”
   • “What is the Kubernetes control plane?”
   • “What are the main components of a Kubernetes control-plane node?”

8. How does Kubernetes handle rolling updates and rollbacks?

   Asked in 4 of 106 interviews · last asked Sep 4 · Concept · Mid-level

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   For a Deployment, Kubernetes gradually replaces old Pods with new ones during a rolling update. It uses readiness checks and update limits to control availability. To roll back, I use `kubectl rollout undo` to restore a previous Pod template, if its revision is retained. A stalled update does not automatically trigger a rollback.

   • maxSurge limits extra Pods; maxUnavailable limits how many desired Pods can be unavailable during the update.
   • Readiness probes help prevent traffic from reaching Pods before they are ready.
   • Rollbacks restore the Pod template, not database changes or external configuration.

   CodeCopy

   kubectl set image deployment/web web=nginx:1.28
   kubectl rollout status deployment/web
   kubectl rollout history deployment/web
   kubectl rollout undo deployment/web
   kubectl rollout status deployment/web

   What the interviewer checks: The interviewer checks whether you understand controlled Pod replacement, availability settings, and rollback limits.

   Other ways it was asked

   • “How do rolling updates work in Kubernetes?”
   • “How does a rolling update work in Kubernetes?”

9. What is the role of a Service in Kubernetes?

   Asked in 4 of 106 interviews · last asked Jul 27 · Concept · Junior

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   A Kubernetes Service gives clients a stable way to reach a group of Pods, even when Pods are replaced and their IP addresses change. It usually selects Pods by labels and sends traffic to ready endpoints. Its type controls whether access is internal or exposed outside the cluster.

   • ClusterIP, the default type, provides an internal virtual IP; cluster DNS provides a name.
   • NodePort and LoadBalancer support external access; LoadBalancer needs a supported load balancer implementation.
   • A headless Service provides endpoint discovery without a virtual IP or Service-level load balancing.

   What the interviewer checks: The interviewer is checking whether you understand stable Pod access, service discovery, and internal versus external exposure.

   Other ways it was asked

   • “What is the role of a Kubernetes service?”
   • “What is a Service used for in Kubernetes?”
   • “What is a Service in Kubernetes, and why is it needed?”

10. How would you identify what is consuming disk space on a Linux server running low?

    Asked in 3 of 106 interviews · last asked Oct 7 · Scenario · Mid-level

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    I start with `df -h` to find the full filesystem, then use `du` to find its largest directories. I drill down and use `find` to list large files. I also check inode use with `df -i`. If `df` shows much more usage than `du`, I check for deleted files still held open.

    • Use `du -x` and `find -xdev` to stay on the affected filesystem.
    • Many small files can exhaust inodes even when disk space remains.
    • Deleted files still use space until all processes close them.
    • Confirm what large files contain before deleting or truncating them.

    CodeCopy

    df -h
    df -i
    # Replace / with the affected filesystem's mount point.
    sudo du -xhd1 / | sort -h
    sudo find / -xdev -type f -size +1G -printf '%s %p\n' | sort -nr | head -20
    sudo lsof +L1

    What the interviewer checks: The interviewer checks whether you can locate disk usage, recognize less obvious causes, and avoid unsafe cleanup.

    Other ways it was asked

    • “A disk is running out of space. How would you quickly identify what is consuming it?”
    • “How would you identify and filter for files that are consuming disk space on a Linux server?”
    • “How do you identify what is using disk space on a Linux server that is running low?”

11. What is a multi-stage Docker build, and how do you implement one?

    Asked in 3 of 106 interviews · last asked Sep 23 · Tooling · Mid-level

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    A multi-stage Docker build uses several FROM instructions in one Dockerfile. I name a build stage with AS, then use COPY --from to copy its output into a smaller runtime stage. This keeps build tools out of the final image. I build it with docker build -t myapp .

    • Use it when compilation or packaging needs tools that the running app does not need.
    • The last stage is the default final image; --target selects a different stage.
    • Copy all required runtime files, but leave out unnecessary source code, build tools, and temporary files.

    CodeCopy

    # Go project with go.mod and a main package at its root.
    FROM golang:1.25 AS build
    WORKDIR /src
    COPY . .
    RUN CGO_ENABLED=0 go build -o /app .
    FROM scratch
    COPY --from=build /app /app
    USER 65532:65532
    ENTRYPOINT ["/app"]
    # scratch has no shell or CA certificates; add runtime files if needed.

    What the interviewer checks: The interviewer checks whether you can separate build dependencies from runtime needs and create a working, smaller image.

    Other ways it was asked

    • “What are multi-stage Docker builds, and when would you use them?”
    • “What are Docker multi-stage builds, and when would you use them?”
    • “How does a Docker multi-stage build work?”

12. What is a Dockerfile, and what is it used for?

    Asked in 3 of 106 interviews · last asked Oct 7 · Concept · Junior

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    A Dockerfile is a text file with instructions for building a container image. It defines the base image, application files, dependencies, and default startup command. Docker uses it during a build to create an image, which can then be used to run containers.

    • A Dockerfile builds an image; it does not start a container.
    • Copy dependency files and install dependencies before copying frequently changing code to reuse cached layers.
    • Use a small, trusted base image and multi-stage builds to keep build tools out of the final image.
    • Use .dockerignore to exclude unnecessary files from the build context, and never put secrets in the image.

    What the interviewer checks: The interviewer checks whether you understand how Docker images are built and how to make builds efficient.

    Other ways it was asked

    • “What is a Dockerfile?”
    • “What is a Dockerfile, and what are best practices for making it efficient?”

13. How does the Kubernetes Horizontal Pod Autoscaler work when it is based on metrics?

    Asked in 3 of 106 interviews · last asked Oct 7 · Concept · Mid-level

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    The Kubernetes Horizontal Pod Autoscaler adjusts a workload’s replica count by comparing measured metrics with configured targets. It checks periodically and scales within minimum and maximum replica limits. It can use CPU, memory, custom metrics such as request rate, or external metrics such as queue length.

    • CPU and memory utilization percentages are measured against resource requests, not limits.
    • Resource metrics usually come from Metrics Server; custom and external metrics need suitable metrics API adapters.
    • With multiple metrics, HPA uses the largest recommended replica count; metric errors can prevent scaling down.
    • Tolerance, stabilization windows, and scaling policies help prevent rapid changes in replica count.

    What the interviewer checks: The interviewer checks whether you understand the metrics control loop, metric sources, and limits on scaling.

    Other ways it was asked

    • “What is the Kubernetes Horizontal Pod Autoscaler, and how does it scale workloads?”
    • “How does the Kubernetes Horizontal Pod Autoscaler (HPA) work, and which metrics can it use?”

14. How would you troubleshoot a Kubernetes pod that keeps crashing or enters CrashLoopBackOff?

    Asked in 3 of 106 interviews · last asked Oct 7 · Scenario · Mid-level

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    I check the pod status, events, and logs from the current and previous container runs. I inspect the last exit reason, memory limits, health probes, configuration, and dependencies. I compare recent changes, fix the cause, and confirm that the container stays running and becomes ready.

    • CrashLoopBackOff means Kubernetes is delaying repeated container restarts; it is not the root cause.
    • Check the last termination reason and exit code; OOMKilled points to a memory issue.
    • Failed startup or liveness probes can restart containers; failed readiness probes do not.
    • Check application errors, missing Secrets or ConfigMaps, dependency failures, and recent deployments.

    CodeCopy

    POD=my-pod; NAMESPACE=default; CONTAINER=my-container
    kubectl describe pod "$POD" -n "$NAMESPACE"
    kubectl logs "$POD" -n "$NAMESPACE" -c "$CONTAINER" --previous
    kubectl logs "$POD" -n "$NAMESPACE" -c "$CONTAINER"

    What the interviewer checks: The interviewer is checking whether you use logs and Kubernetes evidence to find the cause instead of repeatedly restarting the pod.

    Other ways it was asked

    • “A Kubernetes pod is in CrashLoopBackOff. How would you diagnose the problem?”
    • “Suppose an application is crashing randomly in Kubernetes. How would you troubleshoot it?”
    • “How would you troubleshoot a Kubernetes pod that is crashing frequently?”

15. What is a deployment in Kubernetes?

    Asked in 3 of 106 interviews · last asked Sep 4 · Concept · Junior

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    A Kubernetes Deployment manages replicated Pods, usually for a stateless application. You declare the desired replica count and Pod template, and it manages ReplicaSets to keep Pods matching that state. It supports scaling, rolling updates, and rollbacks to earlier Pod templates.

    • A Deployment manages ReplicaSets, which create and replace Pods.
    • Rolling updates gradually replace old Pods with new ones.
    • You can change the replica count to scale the application.
    • Use a StatefulSet when Pods need stable identities or persistent storage tied to each Pod.

    What the interviewer checks: The interviewer checks whether you understand desired state, Pod management, and how Deployments handle application updates.

    Other ways it was asked

    • “What is a Deployment in Kubernetes, and what is its purpose?”
    • “What is a Kubernetes Deployment, what is it used for, and why would you create one?”

16. What is the difference between an Application Load Balancer, a Network Load Balancer, and a Classic Load Balancer?

    Asked in 3 of 106 interviews · last asked Sep 29 · Concept · Mid-level

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    An Application Load Balancer (ALB) works at layer 7 and routes HTTP and HTTPS requests by rules such as host or path. A Network Load Balancer (NLB) works at layer 4 and handles traffic such as TCP and UDP. A Classic Load Balancer (CLB) is the older option, supporting basic connection-level and HTTP routing without ALB’s advanced rules.

    • Choose ALB for web applications that need host-based or path-based routing.
    • Choose NLB for non-HTTP traffic, high performance, or static IP addresses per Availability Zone.
    • Both ALB and NLB can terminate TLS; HTTPS support alone does not decide the choice.
    • CLB mainly serves existing deployments; prefer ALB or NLB for new systems.

    What the interviewer checks: The interviewer checks whether you can choose an AWS load balancer based on protocols and routing needs.

    Other ways it was asked

    • “What is the difference between an Application Load Balancer and a Network Load Balancer?”
    • “What is the difference between a Classic Load Balancer and an Application Load Balancer on AWS?”

17. What is a Terraform state file?

    Asked in 3 of 106 interviews · last asked Oct 20 · Concept · Junior

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    A Terraform state file is a record that links resources in your Terraform configuration to real infrastructure. It stores resource IDs, attributes, and other details Terraform needs to manage them. Terraform uses state, configuration, and information from the provider to plan changes.

    • State is not the configuration itself; it records which real resources Terraform manages.
    • State can contain secrets, so restrict access and protect stored copies.
    • Teams should share remote state and use locking where supported to prevent conflicting updates.

    What the interviewer checks: The interviewer checks whether you understand how Terraform tracks resources and why state needs secure, shared storage.

    Other ways it was asked

    • “What is a Terraform state file and why is it important?”
    • “What is the purpose of a Terraform state file?”

18. How do you handle your Kubernetes cluster security?

    Asked in 3 of 106 interviews · last asked Sep 4 · Scenario · Senior

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    I secure the cluster in layers, starting with least-privilege RBAC and strong authentication. I restrict API access, enforce Pod Security Standards, and use NetworkPolicies with a network plugin that supports them. I encrypt Secrets at rest and limit who can read them. I also patch nodes and Kubernetes, scan container images, and monitor audit logs.

    • Use individual identities and narrowly scoped service accounts; avoid shared admin credentials.
    • Block privileged containers and require non-root users where possible.
    • Apply default-deny network policies, then allow only required traffic.
    • Kubernetes Secrets are base64-encoded, not encrypted by default; configure encryption at rest.

    What the interviewer checks: The interviewer checks whether you protect access, workloads, networking, and sensitive data through ongoing security controls.

    Other ways it was asked

    • “How do you secure a Kubernetes cluster?”
    • “Can you explain how you manage access to your Kubernetes cluster?”

19. What is the difference between a symbolic link and a hard link?

    Asked in 2 of 106 interviews · last asked Aug 30 · Concept · Junior

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    A symbolic link points to a path, while a hard link is another name for the same file inode. A symbolic link can cross file systems and point to a directory. Hard links cannot cross file systems and normally cannot link directories. Deleting the target breaks a symbolic link, but other hard links still work.

    • Hard links share file data and permissions because they refer to the same inode.
    • A symbolic link has its own inode and can point to a missing path.
    • Deleting one hard link does not remove the file data while other hard links remain.

    What the interviewer checks: The interviewer is checking whether you understand file identity, path references, and what happens when a link or target is deleted.

    Other ways it was asked

    • “Explain symbolic links versus hard links.”

20. What is the difference between the `df` and `du` commands, and what does each show?

    Asked in 2 of 106 interviews · last asked Aug 14 · Concept · Junior

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    `df` shows used and available space on file systems. `du` shows disk space used by files and directories it scans. With either command, `-h` shows sizes in readable units, such as K, M, and G. Their totals can differ, for example when a deleted file is still open.

    • `df` reports file system totals, not individual directory sizes.
    • `du` adds up allocated space for files and directories it can access.
    • Deleted files still held open use space reported by `df` but are not visible to `du`.

    CodeCopy

    # Show file system space in readable units.
    df -h
    # Show total disk space used by /var/log.
    du -sh /var/log

    What the interviewer checks: The interviewer is checking whether you can distinguish file system capacity from directory usage when investigating disk space.

    Other ways it was asked

    • “What’s the difference between `df -h` and `du -h`?”

Related interview questions

• CI/CD interview questions
• Kubernetes interview questions
• System Design interview questions
• Docker interview questions
• Cloud Engineer interview questions
• Network Engineer interview questions
• System Administrator interview questions
• IT Support and Help Desk interview questions
• Cybersecurity interview questions

How this list is made

Every question here was asked by a real interviewer in a real job interview that a candidate ran MeetAssist in. After the call, the interviewer's questions are pulled from the transcript. Practice sessions, tests, exams and anything that was not a job interview are dropped.

Questions are rewritten so they make sense on their own: names of people, employers and clients are removed, and speech-to-text mistakes are fixed. Small talk, logistics and questions about one candidate's own résumé are left out. Rephrasings of the same question are merged, and the count is the number of different interviews it came up in.

The interviews come from candidates who use MeetAssist, so they lean towards software, data and AI roles: the shares describe these interviews, not every DevOps Engineer interview. Answers to the most asked questions are written and checked by an editor; a "common mistake" is shown only when reviews of real answers in these interviews show it, with the count.

106 interviews, 54 candidates, Nov 2025 to Oct 2026. Updated every month with new interviews.