The Complete Guide to Installing Docker and Running Your First Container

• Prerequisites
• Installing Docker
  • Docker Engine
  • Docker Desktop
• Running Your First Container
• Understanding Images and Containers
• Dockerfiles
• Conclusion

Docker is a containerization platform that allows you to package your applications and dependencies into a single unit that can be run anywhere. This makes it easy to deploy and manage applications, and it can also help to improve security and reliability.

In this blog post, I will walk you through the steps of installing Docker and running your first container. I will also cover some of the basics of Docker, such as images, containers, and Dockerfiles.

Prerequisites

Before you can install Docker, you will need to have the following prerequisites:

• A computer running Windows, macOS, or Linux
• A minimum of 4GB of RAM
• Enough disk space to store Docker images and containers

Installing Docker

There are two ways to install Docker:

• Docker Engine
• Docker Desktop

Docker Engine

Docker Engine is the open source version of Docker. It is free to download and use.

To install Docker Engine on Ubuntu, you can follow the instructions below:

• Update your package index: sudo apt update
• Install Docker Engine, containerd, and Docker Compose: sudo apt install docker-ce docker-ce-cli containerd.io

Docker Desktop

Docker Desktop is a commercial product that includes Docker Engine, as well as other features such as Kubernetes support and a graphical user interface.

Here are the steps on how you can install Docker Desktop on Windows:

• Go to the Docker website: https://www.docker.com/products/docker-desktop/ and click on the “Download for Windows” button.
• The installer will download to your computer. Run the installer and follow the on-screen instructions.
• Once the installation is complete, you will need to restart your computer.
• After your computer has restarted, you can open Docker Desktop by searching for it in the Start menu.
• Docker Desktop will open and you will be able to start using it.

Docker Desktop Windows

Running Your First Container

Once you have installed Docker, you can run your first container by following these steps:

• Open a terminal window.
• Run the following command:

docker run hello-world

This will run the hello-world image, which is a simple image that prints “Hello, world!” to the console.

Here is a step-by-step explanation of what happens when you run the docker run hello-world command:

• The docker run command tells Docker to run a container.
• The hello-world argument tells Docker to run the hello-world image.
• Docker checks to see if the hello-world image is already stored locally. If it is not, Docker will pull the image from Docker Hub.
• Once the image is pulled, Docker creates a container from the image.
• The container starts up and runs the hello-world command.
• The hello-world command prints “Hello, world!” to the console.
• The container stops.

Hello World Docker Image Output

The docker run command can also be used to run other images, such as images that contain applications. For example, you could use the docker run nginx command to run a container that is running the Nginx web server.

When you run the docker run command, Docker will first check to see if the image you are trying to run is already stored locally. If the image is not stored locally, Docker will pull the image from Docker Hub. Docker Hub is a public registry of Docker images.

When Docker pulls an image from Docker Hub, it downloads the image file to your local machine. The image file contains the instructions for creating a container.

Once the image file has been downloaded, Docker creates a container from the image. A container is a running instance of an image. A container includes the application code, its dependencies, and the runtime environment.

The docker run command will also start the container. When the container starts, it will run the command that you specified. In the case of the hello-world image, the command is hello-world. The hello-world command prints “Hello, world!” to the console.

Once the command has finished running, the container will stop. You can then run the docker ps command to see a list of all of the containers that are currently running and docker ps -a to see a list of all of the containers on the system.

docker ps -a Command Output

A post dedicated to Docker commands will be published soon

Understanding Images and Containers

A Docker image is a blueprint for a container. It includes the application code, as well as the operating system and any dependencies that the application needs.

A Docker container is a running instance of an image. It is a self-contained environment that includes everything that the application needs to run.

Docker containers and images will be covered more in depth in the future posts

Dockerfiles

A Dockerfile is a text file that describes how to build a Docker image. It contains a series of commands that are executed in order to create the image. Sample hello-world dockerfile contents is given below:

FROM scratch
COPY hello /
CMD ["/hello"]

Dockerfile will be covered in depth in the upcoming posts

Conclusion

In this blog post, I have walked you through the steps of installing Docker and running your first container. I have also covered some of the basics of Docker, such as images, containers, and Dockerfiles.

I hope you found this blog post informative. If you have any questions, please feel free to leave a comment below.