okd/roles/container_runtime/tasks/docker_sanity.yml

---
# Sanity checks to ensure the role will complete and provide helpful error
# messages for common problems.

- name: Error out if Docker pre-installed but too old
  fail:
    msg: "Docker {{ curr_docker_version.stdout }} is installed, but >= {{ l_required_docker_version }} is required."
  when:
  - not (curr_docker_version is skipped)
  - curr_docker_version.stdout != ''
  - curr_docker_version.stdout is version_compare(l_required_docker_version, '<')
  - not (docker_version is defined)

- name: Error out if requested Docker is too old
  fail:
    msg: "Docker {{ docker_version }} requested, but >= {{ l_required_docker_version }} is required."
  when:
  - docker_version is defined
  - docker_version is version_compare(l_required_docker_version, '<')