I have a limited number of IPv4 addresses available to me on my servers. So I am really frugal with how I assign them.

Whenever possible, my preference is to use NAT off of the main Proxmox IP. However I struggled to get this setup while also using the built-in Proxmox firewall that comes in version 4.0. Having an enabled firewall is an absolute requirement for me.

In this article I have documented the final working solution. (more…)