We are currently using OpenShift, and we want to use Docker instead. We just started attempting the migration.
We do not use Docker images to deploy to OpenShift. Rather, the deployments were originally made by creating a "deployments/" directory with the application in it and using the "oc new-app" command.
It is my understanding that OpenShift uses Docker. If OpenShift is creating and deploying Docker images behind the curtain, then I would think there would be a way to get that Docker image for testing.
If there is any material for doing this, I can't find it as it is being drowned out in my searches with lots of other hits. All my searching is producing mostly results for deploying Docker images to OpenShift, but that is the opposite of what I am looking for.
How can I pull a Docker image out of OpenShift?
Based on information from @MichaelHampton in comments, the migration is specifically from OpenShift Origin to Docker. We have OpenShift set up on a local server; I do not believe we are using any Red Hat hosted services for any of this, as the company paid Red Hat a bunch of money to have them help us set it up locally when the original decision was made to use OpenShift.
The decision to migrate to Docker is not mine, so I cannot personally just call it off. However, if this is not a good idea, as was hinted at in comment, then I can bring this up with the decision makers, and they are reasonable and would consider good arguments. So a frame challenge of "Reverse course! Here be dragons, because... (reason this is terrible)" would be a reasonable answer.