I have a fundamental disconnect here.
- Why is the QNAP being ‘bombarded’ at all? What about your modem/router or did you bypass and plug the ISP directly into the NAS? (BAD decision)
- Should one opt to do the direct-connect ISP method: One of the best firewalls (pfSense) is available for QNAP from QNAP. It is a full, proper, stateful, firewall with all the trimmings. Might I suggest use it ?
- The better decision is to spend the few $$$ and get a proper Netgate box with pfSense in it or build your own from the FREE Community version