'ping default gateway to imply external connectivity'

def _check_network_external_connectivity(self):

    if (not CONF.network.public_network_id):
        msg = 'public    network    not    defined.'
        LOG.info(msg)
        return
    v4_subnets = [s for s in self.os_admin.subnets_client.list_subnets(network_id=CONF.network.public_network_id)['subnets'] if (s['ip_version'] == 4)]
    self.assertEqual(1, len(v4_subnets), ('Found    %d    IPv4    subnets' % len(v4_subnets)))
    external_ips = [v4_subnets[0]['gateway_ip']]
    self._check_server_connectivity(self.floating_ip_tuple.floating_ip, external_ips)
