Running Your First Container

With Docker installed, you can start by running your first container.

Open a terminal window and enter the following command:

docker run hello-world

You will be presented with the following response:

The hello-world image is a minimal container that has a single program that print the message shown above in the terminal window.

To view all container that are currently running or have run in the past, use the following command:

docker ps -a

Notice that the first column shows the container id (421fe5f2e97e) and that the status column shows that the container exited about a minute with status code (0) indicating that there were no error produced during the container runtime.

Let’s go over what happened after running the docker run hello-world command:

1. The Docker client reaches out to the daemon which in turn gets the hello-world image and runs a container from that.
2. Since the hello-world image cannot be found on the local machine, the Unable to find image 'hello-world:latest' message is printed to the console.
3. The daemon connects to the default public registry, i.e., Docker Hub and pulls the latest version of the hello-world image.
4. The Docker daemon creates a new container form the pulled image and then runs the container.