Deploy image to kubernetes without storing the image in a dockerhub

Question

I'm trying to migrate from docker-maven-plugin to kubernetes-maven-plugin for an test-setup for local development and jenkins-builds. The point of the setup is to eliminate differences between the local development and the jenkins-server. Since docker built the image, the image is stored in the local repository and doesn't have to be uploaded to a central server where the base-images are located. So we can basically verify our build without uploading anything to the server and the images is discarded after the task is done (running integrationstests).

Is there a similar way to trick kubernetes to store the image into the local repository without having to take the roundtrip to a central repository? Eg, behave as if the image is already downloaded? Note that I still need to fetch the base-image from the central repository.

Answer 1

If you don't want to use any docker repo (public or private), you can use what is called Pre-pulled-images. This is a bit annoying as you need to make sure all the kubernetes nodes have the images there and also set the ImagePullPolicy to Never in every kubernetes manifest.

In your case, if what you call local repository is some private docker registry, you just need to store the credentials to the private registry in a kubernetes secret and either patch you default service account with ImagePullSecrets or your actual deployment/pod manifest. More details about that https://kubernetes.io/docs/tasks/configure-pod-container/pull-image-private-registry/