docs: def wait_ssh(roles, retries=100, interval=30):
      """Wait for all the machines to be ssh-reachable
  
      Let ansible initiates a communication and retries if needed.
  
      Args:
          inventory (string): path to the inventoy file to test
          retries (int): Number of time we'll be retrying an SSH connection
          interval (int): Interval to wait in seconds between two retries
      """
      utils_playbook = os.path.join(ANSIBLE_DIR, 'utils.yml')
      options = {'enos_action': 'ping'}
  
      for i in range(0, retries):
          try:
              run_ansible([utils_playbook],
                          roles=roles,
                          extra_vars=options,
                          on_error_continue=False)
              break
          except EnosUnreachableHostsError as e:
              logger.info("Hosts unreachable: %s " % e.hosts)
              logger.info("Retrying... %s/%s" % (i + 1, retries))
              time.sleep(interval)
      else:
          raise EnosSSHNotReady('Maximum retries reached')