Comment 0 for bug 1719288

prepare command prepares a list of docker images for services enabled.

openstack overcloud container image prepare --namespace tripleoupstream --tag latest --env-file ~/docker_registry.yaml -e /usr/share/triple-common/environments/services-docker/neutron-opendaylight.yaml

produces just ODL related images.

Add docker.yaml as default service-environment-file so that above commands produces images for all supported services + ODL. Adding to many env files is confusing to users.