RDP from physical LAN to OPNsense VM LAN problem


May 29, 2020
I installed OPNsense as a VM in Proxmox 8 to practice with this firewall. It gets an IP (its main WAN port) from my physical router which manages my home LAN.
I set a WAN pass rule in OPNsense to allow my pc on my physical LAN to get access both to OPNSense GUI, VMs and physical machines on its internal LAN.
Of course, I also set a route up on my router for the Opensense VM's LAN. I can ping the laptop connected to a Proxmox NIC that is on the OPNSense LAN.

Here is the interfaces setup:

auto lo
iface lo inet loopback

iface enp3s0 inet manual

iface enp5s1 inet manual

iface enx0050b6e77283 inet manual

auto vmbr0
iface vmbr0 inet static
        bridge-ports enp3s0
        bridge-stp off
        bridge-fd 0

auto vmbr1
iface vmbr1 inet manual
        bridge-ports enp5s1
        bridge-stp off
        bridge-fd 0

auto vmbr2
iface vmbr2 inet manual
        bridge-ports none
        bridge-stp off
        bridge-fd 0

auto vmbr3
iface vmbr3 inet static
        bridge-ports enx0050b6e77283
        bridge-stp off
        bridge-fd 0

vmbr3 is set on a USB-ethernet device I added as an additional NIC to my Proxmox machine in order to pratice with dual WAN failover in OPNsense, or other routers I have been tinkering with. Anyway, nothing was connected to this usb nic when I try to RDP to my laptop.

However, when I connect to the laptop via Windows RDP a problem occurs that I can't still manage to get my head around, after I log in the connection gets closed after a while (from 10 to 20 secs), sometimes I can't even connect to the machine.

remote desk warning.jpg

I ran Wireshark on my Windows machine to try to figure out the issue. I don't know if the screenhot below can be of any help:


IP is my laptop address on the OPNsense LAN. is my physical PC IP.
AFAIK, I don't think that the problem has anything to do with OPNsense. I have the same problem if I run a Mikrotik x86 VM with pretty much the same network setup in Proxmox.

Could you help me figure it out please?
Last edited:


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