lesson-3

Registry

Registry is a place where you can upload and reuse the images uploaded by other users.

Docker Hub is a registry maintained by Docker itself. You can upload your own images, or find all the official images from there, even the hello-world:latest image that we used earlier.

Docker has a command to search for images through CLI, for example:

docker search nginx

Pull an image

In the earlier lesson when we ran, docker run hello-world:latest, it pulled the image itself. But it is possible to pull an image beforehand to save time:

docker pull <image name>

It will take some time to pull, depending on the size of the image.

List the images

Let's see where does it show up after its pulled:

$ docker image ls

The list will show you all the images, with their tags and the time when they were updated.

Remove an image

Sometimes you've pulled so many images that your disk run out of space. So you should remove all the unwanted images:

$ docker rmi <image name>

rmi stands for remove image.

Let's talk a little more about images in the next lesson.