DevOps Engineer Interview Questions
372 questions across 38 categories
The bulk of a working DevOps engineer's day-to-day: hands-on tooling, common troubleshooting, and the practical judgment calls that come up once you're actually operating systems.
A service accepts GitHub webhook payloads and triggers a deployment based on push events, but doesn't verify where the request actually came from. What's the risk, and how do you fix it?
IntermediateGitHub6 min
A teammate used 'cache' to pass compiled build output from the build job to the deploy job, and it intermittently fails to find the files. What did they get wrong?
IntermediateGitLab CI/CD6 min
A shared library lives in its own GitLab project, consumed by 5 downstream application projects. How would you trigger those downstream pipelines automatically when the library changes?
IntermediateGitLab CI/CD6 min
Your GitLab pipeline runs 6 stages sequentially, but half your jobs don't actually depend on each other. How would you use 'needs' to speed this up?
IntermediateGitLab CI/CD6 min
How do you make sure a production deployment token stored as a CI/CD variable can only ever be used by pipelines running against your main branch, not a random feature branch?
IntermediateGitLab CI/CD6 min
A new job you added to .gitlab-ci.yml is stuck 'pending' forever and never picked up by any runner. What's the most likely cause, and how do you fix it?
BeginnerGitLab CI/CD5 min
What's the difference between a branch pipeline and a merge request pipeline in GitLab CI, and why does it matter which one actually runs for a given push?
IntermediateGitLab CI/CD7 min
What debugging challenge does a GitLab merged results pipeline introduce that a plain branch pipeline doesn't, when a job fails?
IntermediateGitLab CI/CD6 min
How would you write .gitlab-ci.yml rules to prevent duplicate pipelines from firing for both a branch push and its merge request?
IntermediateGitLab CI/CD6 min
How does GitLab's pipeline trigger distinction compare to GitHub Actions' push vs pull_request trigger?
IntermediateGitLab CI/CDGitHub Actions6 min
How would you configure GitLab merge request approval rules so that changes to a payments module always require sign-off from the payments team specifically, not just any two approvers?
IntermediateGitLab CI/CD6 min
A teammate accidentally merged a merge request that was still a work in progress, because nothing in GitLab's workflow signaled it wasn't ready. How would you prevent this going forward?
BeginnerGitLab CI/CD5 min
Two approved merge requests are merged to main within minutes of each other, and the second one breaks the build even though it passed CI on its own branch. How does GitLab's merge trains feature prevent this?
IntermediateGitLab CI/CD6 min
Reviewers keep approving frontend PRs based on reading the diff alone, and subtle visual bugs keep slipping through to production. How would GitLab Review Apps address this?
IntermediateGitLab CI/CD6 min
A merge request's 'Merge' button is greyed out with the widget stuck on 'Checking if merge request can be merged...' indefinitely, even though the pipeline passed. How do you debug this?
IntermediateGitLab CI/CD6 min
What's the actual difference between GitLab's Developer, Maintainer, and Owner roles in terms of what each one can do to a protected branch and CI/CD variables?
BeginnerGitLab6 min
How do GitLab's group-level and project-level roles interact when a user has different roles assigned at each level?
IntermediateGitLab6 min
How would you structure GitLab protected branch rules differently for a fast-moving startup versus a regulated environment requiring strict change control?
IntermediateGitLab6 min
What's the difference between a "Protected" and a "Masked" GitLab CI/CD variable, and why would you want both on the same variable?
BeginnerGitLab CI/CD5 min
An Argo CD application shows OutOfSync even though the pods running in the cluster look correct and healthy. What would you check?
IntermediateArgo CDKubernetesGitOps8 min
What's the difference between Argo CD's Sync status and Health status, and why does treating them as the same thing cause confusion?
IntermediateArgo CDKubernetes6 min
What problem does the 'app of apps' pattern actually solve in GitOps, and when would you reach for it instead of just managing each application independently?
IntermediateGitOpsArgo CD6 min
An engineer manually ran kubectl edit against a production Deployment to fix an urgent issue, bypassing Git. What happens next in a GitOps-managed cluster, and why does that matter?
IntermediateGitOpsKubernetes6 min
In a GitOps setup, how do you actually promote a change from staging to production — is it a separate deploy, or literally the same Git commit moving between environments?
IntermediateGitOps7 min