Private Registry/Docker Hub Image Selection Priority

I have a container orchestration ecosystem running on mesos/marathon with high availability. I also have a private docker registry for local image downloads so that I don’t have to go out to the Hub and pull images. In Marathon, to create docker containers I have to explicit define the image name as such


I essentially want my system to work such that it on my agents that hold the containers would poll my private repository, check if the image already is stored, and if not to pull the image. Currently, I have the pass through cache system setup so that all docker pulls will cache the image in my private registry. The problem is the fact if I want to use my images in my docker registry, that I would have to include the hostname/port to access it.

This would mean that I could just use an image name in my Marathon configuration file. This would try to run a container [1]checking the local system, [2]then the private registry, and [3]finally pull from the docker hub.