code: def _id_map(minion_id, dns_name):
      '''
      Maintain a relationship between a minion and a dns name
      '''
      bank = 'digicert/minions'
      cache = salt.cache.Cache(__opts__, syspaths.CACHE_DIR)
      dns_names = cache.fetch(bank, minion_id)
      if not isinstance(dns_names, list):
          dns_names = []
      if dns_name not in dns_names:
          dns_names.append(dns_name)
      cache.store(bank, minion_id, dns_namesf _id_map(minion_id, dns_name):
      '''
      Maintain a relationship between a minion and a dns name
      '''
      bank = 'digicert/minions'
      cache = salt.cache.Cache(__opts__, syspaths.CACHE_DIR)
      dns_names = cache.fetch(bank, minion_id)
      if not isinstance(dns_names, list):
          dns_names = []
      if dns_name not in dns_names:
          dns_names.append(dns_name)
      cache.store(bank, minion_id, dns_names)
docs: Maintain a relationship between a minion and a dns name