Post #3693297

There’s a few things we don’t know here. Are you hosting more VMs on Proxmox that need network via a virtual switch? Are you providing network to other physical devices as well via a switch, so you need to output to that? Do you want OPNsense to be your gateway and assign IPs, or do you have a router? As you have 3 NICs and sound like you want to use them, let’s assume you aren’t doing RoaS, but this could all be done on one (very busy) NIC. There’s nothing wrong with your plan, but that’s not how I would do it. I just don’t pass through NICs. I bond them or I bridge them. In a virtual world, this sort of task is done with virtual switches. OVS switches at my job. OVS is a lot easier to use than oldskool linux bridges that come installed with Proxmox. There’s already a dropdown in Network where you can build with OVS objects, but you need to add the package. apt install openvswitch-switch For your setup, I might consider (the onboard!) eth3 as my mgt NIC. That might be handy some day if you have to remove that card. Your server will still be online. I would run the WAN line straight to eth1. Add eth1 to a ‘dmz’ virtual switch. Add the OPNsense WAN leg to this dmz virtual switch, so the OPNsense (and nothing else) can directly talk to the upstream router. Create a ‘protected network’ virtual switch. Add the OPNsense LAN leg to this virtual switch. VMs can be a member of this downstream protected network and access any services provided by the OPNsense. If you need to share the OPNsense protected network back out to other devices, add eth3 to to the protected network switch, and ethernet cable out from eth3 to a dumb switch. Plug other external devices into the dumb switch, and they will be protected by your OPNsense, accessing its services. Feel free to ignore me here. I build a lot of big things, so I use enterprise-scale techniques. There’s nothing wrong with your pass-through plan. And … you can do this! I have a somewhat similar setup on my laptop with HyperV, so I can distribute wired (work VPN) and wireless (everything else) internet to guest VMs and the main OS. I made two virtual switches in HyperV. The first switch gets exclusive access to my NIC attached to my VPN device. This is the OPNsense WAN leg. The second switch is the OPNsense LAN leg and VMs are members. Good luck!