@Override
  public NicProfile allocate(
      Network config, NicProfile nic, VirtualMachineProfile<? extends VirtualMachine> vm)
      throws InsufficientVirtualNetworkCapcityException, InsufficientAddressCapacityException {

    if (_networkModel.networkIsConfiguredForExternalNetworking(
            config.getDataCenterId(), config.getId())
        && nic != null
        && nic.getRequestedIpv4() != null) {
      throw new CloudRuntimeException("Does not support custom ip allocation at this time: " + nic);
    }

    NicProfile profile = super.allocate(config, nic, vm);

    boolean _isEnabled = Boolean.parseBoolean(_configDao.getValue(Config.OvsTunnelNetwork.key()));
    if (_isEnabled) {
      return null;
    }

    if (_networkModel.networkIsConfiguredForExternalNetworking(
        config.getDataCenterId(), config.getId())) {
      profile.setStrategy(ReservationStrategy.Start);
      /* We won't clear IP address, because router may set gateway as it IP, and it would be updated properly later */
      // profile.setIp4Address(null);
      profile.setGateway(null);
      profile.setNetmask(null);
    }

    return profile;
  }