Working with Docker Images, Containers, and the DockerHub

1. How do I push an image into Dockerhub?
2. What is the relationship between Docker image and Docker container?
3. What are the advantages of using Docker containers?
4. Why is it a good idea to use official Dockerhub images?
5. How do I pull an image from a private Docker repository?
6. Where are Docker images stored?

How do I push an image into Dockerhub?

To push an image to Docker Hub, you must first name your local image using your Docker Hub username and the repository name that you created through Docker Hub on the web. You can add multiple images to a repository by adding a specific :<tag> to them (for example docs/base:testing ).

What is the relationship between Docker image and Docker container?

Docker images are read-only templates used to build containers. Containers are deployed instances created from those templates. Images and containers are closely related, and are essential in powering the Docker software platform.

What are the advantages of using Docker containers?

Docker: Top 7 Benefits of Containerization

• Key Benefits of Docker Containers. The crucial word here is: agility. ...
• Consistent and Isolated Environment. ...
• Cost-effectiveness with Fast Deployment. ...
• Mobility – Ability to Run Anywhere. ...
• Repeatability and Automation. ...
• Test, Roll Back and Deploy. ...
• Flexibility. ...
• Collaboration, Modularity and Scaling.

Why is it a good idea to use official Dockerhub images?

When to use Official Images

If you are new to Docker, we recommend that you use the Official Images in your projects. These images have clear documentation, promote best practices, and are designed for the most common use cases. Advanced users can review the Official Images as part of your Dockerfile learning process.

How do I pull an image from a private Docker repository?

Make sure the repository is public then this is the set of instructions I followed in command line: Once logout from docker hub and login again.

1. docker logout.
2. docker login --username=YOURUSERNAME Enter password when asked.
3. docker pull "repositoryName"/"imageName"[:tag]

Where are Docker images stored?

On a linux system, docker stores data pertaining to images, containers, volumes, etc under /var/lib/docker. When we run the docker build command, docker builds one layer for each instruction in the dockerfile. These image layers are read-only layers.