1:1 Bridge to Physical NIC pairing


New Member
Jul 24, 2023

I currently have OPNSense virtualized on Proxmox. I have one physical interface, enp2s0, which connects to my modem (WAN). I have created a bridge, vmbr1, for the enp2s0. I want to "join" these two interfaces so that they have the same MAC and IPv6 address and are treated as one (rather than a switch and a device, OPNSense, "plugged in to" the switch), while still getting the benefit of having a bridge interface (for snapshots).

I see that both enp2s0/vmbr1 and OPNSense "plugged in to" vmbr1 are receiving IPv6 IPs (even though enp2s0 and vmbr1 are set to "manual" in my interfaces file). And OPNSense "plugged in to" vmbr1 is receiving an IPv4 IP (which I want).

I only want vmbr1 accessible by a single VM (OPNSense), I do not want the "switch" functionality for vmbr1. The only way I can imagine doing this is via PCI passthrough (and deleting the bridge) but this eliminates my ability to create snapshots. Is there any other way I can create a 1:1 map between the physical NIC and the bridge?

I'm on ATT fiber, so my "modem" is actually a router+modem set to "passthrough mode". I've configured the modem to pass through a WAN IP to vmbr1, but it still gives enp2s0 an IPv6 IP. This is creating problems with IPv6 address assignment in my other VLANs.

I'm not too concerned from a safety perspective since I don't think the physical NIC is exposed to the WAN.

Last edited:
Could I just set the MAC address for the OPNSense network interface to match the MAC of enp2s0/vmbr1? Or would that create issues?


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