When installing OpenShift 4.3+ there is no default route created for the image registry. Therefore we are unable to load in images from outside of the cluster.

To enable the route you must run the following command.

oc patch configs.imageregistry.operator.openshift.io/cluster --type merge -p '{"spec":{"defaultRoute":true}}'

Then to load images in from outside of the cluster first we find the url of the route.

oc get route -n OpenShift-image-registry

returns

NAME             HOST/PORT                                                                                                               PATH      SERVICES         PORT      TERMINATION          WILDCARD
default-route    default-route-openshift-image-registry.apicv10-number-0000.eu-gb.containers.appdomain.cloud             image-registry   <all>     reencrypt            None

Then to log into docker we run the following

docker login <HOST from above> --username admin --password $(oc whoami -t)

The username can be anything. The password is a token that can be retrieve from the oc client.

Now tag your images

docker tag <image>:<tag> <HOST from above>/<namespace>/<image>:<tag>

And push them up

docker push <HOST from above>/<namespace>/<image>:<tag>

and you are good to go.