@Override
 public void releaseVip(Service service) {
   String vip = service.getVip();
   if (vip == null) {
     return;
   }
   List<Subnet> subnets =
       objectManager.find(
           Subnet.class,
           SUBNET.ACCOUNT_ID,
           service.getAccountId(),
           SUBNET.KIND,
           SubnetConstants.KIND_VIP_SUBNET);
   if (subnets.isEmpty()) {
     return;
   }
   Subnet subnet = subnets.get(0);
   poolManager.releaseResource(subnet, service);
 }