This container can be pulled via:
  docker pull registry.opensuse.org/isv/suse/edge/sles16.1/images/sles16.1/ironic-ipa-downloader:3.1.1
  docker pull registry.opensuse.org/isv/suse/edge/sles16.1/images/sles16.1/ironic-ipa-downloader:3.1.1-2.9

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.