code: def _create_hidden_port(self, context, network_id, device_id, fixed_ips,
                              port_type=DEVICE_OWNER_ROUTER_INTF):
          
          port = {'port': {
              'tenant_id': '',  # intentionally not set
              'network_id': network_id,
              'mac_address': ATTR_NOT_SPECIFIED,
              'fixed_ips': fixed_ips,
              'device_id': device_id,
              'device_owner': port_type,
              'admin_state_up': True,
              'name': ''}}
          if extensions.is_extension_supported(self._core_plugin,
                                               "dns-integration"):
                  port['port'].update(dns_name='')
          core_plugin = bc.get_plugin()
          return core_plugin.create_port(context, port)
docs: Creates port used specially for HA purposes.