Where is my Dockerfile with "docker pull ubuntu"?

June 20, 2016 745 views

I really don't see the point of this tutorial:

Since it relies on a docker pull ubuntu image, where can I edit that Dockerfile to customize it further? Shouldn't you typically rely on a Dockerfile for docker containers? The tutorial mentions that Dockerfiles are "beyond the scope" of the tutorial which I just find odd.

1 Answer

Hi @alxvallejo,

In this case, the Docker image is already builded from a Dockerfile, and stored on the Docker hub platform.

When you run the pull command, Docker will just download the latest image of "ubuntu" from https://hub.docker.com/_/ubuntu/

If you click the "xenial/Dockerfile" link on this page, you will see the actual Dockerfile used to build the image.

If you need to customize this image, you should create a Dockerfile, with the first line:

FROM ubuntu

Then you can add all your customizations.

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