Docker interview Questions:
1. Docker Architecture
- Can you explain Docker’s architecture and its main components?
- What is the difference between Docker Engine and Docker Daemon?
- How does Docker handle isolation and resource management within containers?
- What are the key differences between Docker containers and virtual machines?
- How does Docker Networking work? Can you explain the different network drivers available?
2. Containerization Best Practices
- What are some best practices for writing Dockerfiles?
- How do you optimize the size of Docker images?
- What strategies do you use to secure Docker images and containers?
- Can you explain the concept of multi-stage builds in Docker? How do they help in creating efficient images?
- How do you handle persistent storage in Docker containers?
3. Docker Compose
- What is Docker Compose, and how does it differ from Docker Swarm?
- How do you manage multi-container Docker applications using Docker Compose?
- Can you explain the syntax and structure of a docker-compose.yml file?
- How do you use Docker Compose for development, testing, and production environments?
- How do you handle networking between services in a Docker Compose setup?
4. Docker Swarm & Orchestration
- What is Docker Swarm, and how does it compare to Kubernetes?
- How do you set up and manage a Docker Swarm cluster?
- Can you explain the concept of services, tasks, and nodes in Docker Swarm?
- How do you deploy a stack in Docker Swarm using Docker Compose?
- What strategies do you use to manage load balancing and scaling in Docker Swarm?
5. Docker Networking
- How does Docker manage networking between containers?
- Can you explain the different Docker network types (bridge, host, overlay, etc.) and when to use them?
- How do you set up communication between Docker containers on different hosts?
- What is a Docker network namespace, and how does it work?
- How do you troubleshoot network issues in a Docker environment?
6. Docker Security
- How do you secure Docker containers and images?
- What are the common security risks associated with Docker, and how do you mitigate them?
- How do you manage and rotate secrets in Docker containers?
- What tools do you use to scan Docker images for vulnerabilities?
- Can you explain the concept of Docker Content Trust? How does it ensure image integrity?
7. Image Management
- How do you manage Docker images in a CI/CD pipeline?
- What is the difference between a Docker image and a Docker container?
- How do you version and tag Docker images?
- How do you clean up unused Docker images and containers?
- How do you push and pull Docker images to and from a Docker registry?
8. Docker Registries
- What is a Docker registry, and how does it work?
- How do you set up and manage a private Docker registry?
- What are the benefits of using a private Docker registry over Docker Hub?
- How do you secure access to a Docker registry?
- What strategies do you use for managing large-scale Docker image repositories?
9. CI/CD Integration
- How do you integrate Docker with CI/CD pipelines?
- Can you explain a typical CI/CD workflow involving Docker?
- How do you handle Docker image versioning in a CI/CD pipeline?
- How do you test Docker containers in a CI/CD pipeline?
- What tools do you use to orchestrate Docker builds, tests, and deployments in CI/CD?
10. Troubleshooting & Debugging
- How do you troubleshoot a container that is not starting correctly?
- What steps do you take to debug network issues in a Docker environment?
- How do you handle a situation where a Docker container is using too many resources?
- How do you troubleshoot a Docker build that is failing?
- What tools do you use to monitor and log Docker container activity?
11. Advanced Docker Concepts
- What is Docker Overlay Network, and how does it work in a multi-host setup?
- How do you use Docker Volumes, and what are their advantages?
- Can you explain the concept of Docker namespaces and cgroups?
- How do you use Docker secrets for managing sensitive data in containers?
