'Update local DNS entries of all networks on this host.'

@periodic_task.periodic_task(spacing=CONF.dns_update_periodic_interval)
def _periodic_update_dns(self, context):

    networks = objects.NetworkList.get_by_host(context, self.host)
    for network in networks:
        dev = self.driver.get_dev(network)
        self.driver.update_dns(context, dev, network)
