Docker Registry & Hub

What is Docker Hub?

Docker Hub is Docker's official cloud-based registry service. It provides:

• Public repositories for open-source sharing
• Private repositories for enterprise use
• Image versioning and tagging
• Webhooks and integrations with CI/CD pipelines

You can also use self-hosted registries like Harbor or Nexus for internal image storage.

Logging into Docker Hub

Before pushing images to Docker Hub, authenticate using:

docker login

You'll be prompted for your Docker Hub username and password (or access token).

Tagging and Pushing Docker Images

Tag your local image with your Docker Hub username and repository:

docker tag myapp username/myapp:latest

Then push it to Docker Hub:

docker push username/myapp:latest

Pulling Images from Docker Hub

To download an image to your local machine:

docker pull nginx

This pulls the official nginx image from Docker Hub.

Using a Private Docker Registry

You can also set up and push to a private registry using:

docker run -d -p 5000:5000 --name registry registry:2

Tag and push your image to the local registry:

docker tag myapp localhost:5000/myapp
docker push localhost:5000/myapp

Managing Image Versions

• Tag each release using semantic versioning (e.g., v1.0.0, v1.1.0)
• Avoid using :latest in production deployments
• Use automation tools to handle tagging and release pipelines

Security Considerations

• Use private repositories for sensitive or proprietary images
• Enable two-factor authentication on your Docker Hub account
• Scan images regularly for vulnerabilities using tools like Snyk, Trivy, or Docker Scout

Docker registries allow for centralized image distribution, version control, and security management. Using Docker Hub or a private registry ensures your CI/CD pipeline runs smoothly across environments.