DevOps Engineer Technical Interview Questions
运维工程师 · 技术面试（English interview practice）
Top DevOps Engineer technical interview questions — architecture, system design, and hands-on problem solving. Practice explaining your approach out loud and get AI feedback on SpeakInterview.
- You need to design a CI/CD pipeline for a microservices application that requires zero-downtime deployments. The application is containerized with Docker and runs on Kubernetes. How would you approach the pipeline design, and what specific strategies would you use to ensure zero downtime?
- You have a Linux server running a high-traffic web application. Recently, you observed that the server's memory usage is consistently high and the swap space is being used, causing performance degradation. How would you diagnose the issue, and what actions would you take to optimize memory usage?
- Your team is experiencing intermittent high latency in a Kubernetes cluster. Describe a systematic approach you would take to diagnose the root cause. How would you use observability tools to isolate the issue between the application, the network, and the infrastructure?
- You have a Dockerized application that needs to be deployed to a Kubernetes cluster. The application is stateful and requires persistent storage. Compare and contrast using a StatefulSet with a Deployment for this scenario. When would you choose one over the other, and what are the trade-offs in terms of scaling and data management?
- Your CI/CD pipeline deploys a Dockerized microservice to a Kubernetes cluster. How would you design the pipeline to ensure zero-downtime deployments, and what trade-offs would you consider between rolling updates and blue-green deployments?
- You need to optimize a Linux server that runs a high-traffic Nginx reverse proxy and a PostgreSQL database. The server has 16 CPU cores and 64GB RAM. Recently, response times have increased significantly. How would you approach the diagnosis and what specific system-level metrics would you examine?
- Your CI/CD pipeline has a Docker build step that takes 15 minutes, and you need to reduce it to under 5 minutes. What specific strategies would you employ, and what trade-offs would you consider between build performance and image size or security?
- You have a centralized logging system using the ELK stack, but it's becoming slow and expensive to ingest logs from hundreds of containers. How would you redesign your logging architecture to improve performance and reduce cost? What trade-offs would you make between log retention, granularity, and query speed?
- A Docker container running a critical application is experiencing high CPU usage and intermittent out-of-memory (OOM) kills. How would you diagnose and resolve this issue in a production environment?
- Imagine you are responsible for migrating a legacy monolithic application to Kubernetes. The application has stateful components and requires persistent storage. How would you design the Kubernetes deployment to ensure data durability and high availability?
- Your team's Linux servers are experiencing random OOM kills, but the memory usage reported by 'free' seems normal. How would you investigate and diagnose the issue? What tools and commands would you use, and how would you identify the root cause?