Docker login and authentication - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of the docker login command?

The docker login command is used to authenticate a user to a Docker registry by providing credentials. This allows the user to push or pull private images securely.

beginner

Which file stores Docker login credentials on your local machine?

Docker stores login credentials in a file called config.json located in the ~/.docker/ directory on your local machine.

beginner

How do you log in to a private Docker registry named myregistry.example.com?

Use the command: <br>docker login myregistry.example.com<br>Then enter your username and password when prompted.

beginner

What happens if you try to pull a private image without logging in first?

Docker will return an authentication error because it cannot access private images without valid credentials.

beginner

How can you log out from a Docker registry?

Use the command docker logout [registry]. If no registry is specified, it logs out from Docker Hub by default.

What command do you use to authenticate to Docker Hub?

A docker login

B docker push

C docker pull

D docker logout

The docker login command is used to authenticate to Docker Hub or any Docker registry.

Where does Docker store your login credentials locally?

A ~/.docker/config.json

B /etc/docker/credentials

C ~/.docker/login.txt

D /var/lib/docker/auth

Docker stores credentials in the config.json file inside the ~/.docker/ directory.

What will happen if you try to pull a private image without logging in?

A Docker automatically logs you in

B You get an authentication error

C The image downloads successfully

D The image is deleted

Pulling private images requires authentication; otherwise, Docker returns an error.

How do you log out from Docker Hub?

A docker disconnect

B docker login --logout

C docker remove login

D docker logout

The docker logout command logs you out from Docker Hub or a specified registry.

Which information do you need to provide when running docker login?

A Image name

B Container ID

C Username and password

D Dockerfile path

You must provide your username and password to authenticate with the registry.

Explain the steps to log in to a private Docker registry and why it is necessary.

Think about how you prove your identity to access private content.

Describe where Docker stores your login credentials and how you can log out from a registry.

Consider the local files and commands managing your login state.