def reset_bios_to_default(self):
        """Resets the BIOS settings to default values.

        :raises: IloError, on an error from iLO.
        """
        sushy_system = self._get_sushy_system(PROLIANT_SYSTEM_ID)
        try:
            sushy_system.bios_settings.update_bios_to_default()
        except sushy.exceptions.SushyError as e:
            msg = (self._("The Redfish controller is unable to update bios "
                          "settings to default Error %(error)s") %
                   {'error': str(e)})
            LOG.debug(msg)
            raise exception.IloError(msg)