Pushing images to registry in Jenkins - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of pushing a Docker image to a registry?

Pushing a Docker image to a registry stores the image in a central place so it can be shared and used by others or deployed on different machines.

intermediate

Which Jenkins plugin helps with Docker image building and pushing?

The 'Docker Pipeline' plugin allows Jenkins to build, tag, and push Docker images within pipeline scripts.

intermediate

What Jenkins pipeline step is used to push a Docker image to a registry?

The 'docker.withRegistry' block combined with 'docker.image.push()' is used to authenticate and push images to a Docker registry.

beginner

Why do you need to login to a Docker registry before pushing an image?

Logging in authenticates your Jenkins job with the registry, allowing it to upload images securely and preventing unauthorized access.

beginner

What is a common format for tagging Docker images before pushing?

Images are tagged with the registry URL, repository name, and version or 'latest', for example: 'myregistry.com/myapp:latest'.

Which Jenkins pipeline syntax is used to push a Docker image to a registry?

A docker.pull('myimage')

B sh('docker push myimage')

C docker.build('myimage').run()

D docker.withRegistry('https://registry.url', 'credentialsId') { docker.image('myimage').push() }

Option D shows the correct Jenkins pipeline syntax to authenticate and push an image to a registry.

Why is tagging a Docker image important before pushing?

A It identifies the image version and destination repository.

B It deletes the image after pushing.

C It compresses the image to save space.

D It runs the image automatically.

Tagging helps specify the image version and where it should be stored in the registry.

What does the 'docker.withRegistry' step do in Jenkins?

A Builds a Docker image.

B Logs into the Docker registry for pushing or pulling images.

C Deletes images from the registry.

D Runs a Docker container.

'docker.withRegistry' authenticates Jenkins with the registry to allow image push or pull.

Which credential type is typically used for Docker registry login in Jenkins?

A GPG key

B SSH key

C Username and password

D API token for GitHub

Docker registries usually require username and password credentials for login.

What happens if you try to push a Docker image without logging in to the registry?

A Push will fail due to authentication error.

B Image will push successfully without login.

C Image will be deleted locally.

D Jenkins will automatically login.

Without login, the registry rejects the push because it cannot verify permissions.

Explain the steps to push a Docker image to a registry using Jenkins pipeline.

Think about building, tagging, authenticating, and pushing.

Why is it important to use credentials securely when pushing images in Jenkins?

Consider security and best practices.