Dockerfile Best Practices
What is the difference between a Docker image and a container? What are some Dockerfile best practices?
What is the difference between a Docker image and a container? What are some Dockerfile best practices?
An image is a read-only template containing the application and dependencies. A container is a running instance of an image. Best practices include: use official base images, minimize layers by combining RUN commands, use multi-stage builds to reduce image size, don't run as root, use specific version tags instead of latest, and order instructions from least to most frequently changing to leverage layer caching.
Container optimization directly impacts deployment speed, security, and costs. Smaller images deploy faster, have fewer vulnerabilities, and cost less to store. Understanding these concepts helps DevOps engineers build efficient CI/CD pipelines.
Optimized multi-stage Dockerfile
- Using 'latest' tag in production
- Running containers as root
- Not using .dockerignore to exclude unnecessary files
- What is the difference between COPY and ADD?
- How does layer caching work in Docker builds?
- What is the difference between CMD and ENTRYPOINT?
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