I'm getting ready to start my journey in learning to use OpnSense. It's going to be running on a Dell Optiplex with one onboard network port and one 4-port PCIe network card. I might virtualize OpnSense as a VM on proxmox, since I run proxmox in my other server box.

I'm thinking of keeping my existing router (a ddwrt router) and putting the OpnSense box behind that router. So the WAN side of OpenSense (one of the four PCIe ports) will be DHCPed from the ddwrt router, and I'd also have a cable from ddwrt router to the onboard ethernet port for interacting with proxmox hypervisor from the outer lan. So if I mess things up, I can always manage it from the outer lan.

And as I slowly figure things out, I'll put devices onto the OpenSense LAN.

I'm just not sure what kind of issues I'll have being double NAT'd. I don't really have any services running that I need to get to from the internet. I think I can talscale myself in even in the double NAT situation.

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