Subnet from hetzner to pfsense vm?


New Member
Oct 18, 2023
Hi, I am new here and new to proxmox.
I am trying to help a friend who got a server from hetzner, I will write down the setup first before I ask for help.
2 Network cards from hetzner
Main IP for proxmox interface:

We have asked for a 2nd nic but if it is not needed, we will ask to remove it but if it helps, we will keep it.
Usable IPs from .73 to .78

Our goal is to pass the subnet to a pfsense or opnsense or anyother firewall/router vm in order to protect some vms that we will create as soon as we make the network work.

I have tried to add the subnet to WAN of pfsense in VMBR0, doesn't work.
I have tried to add the subnet to a new VMBR1 that is attached to the 2nd nic, didn't work either.
I have tried to add the subnet to the 2nd nic directly didn't work.
I have done pci-e passthrough and added the 2nd nic in the vm, didn't work as well.
I have tried the passthrough card as both WAN and LAN but again didn't work.

I did the "sysctl -w net.ipv4.ip_forward=1" and "sysctl -w net.ipv6.conf.all.forwarding=1" and done the above steps again, same results.

I am at loss because I have never done this before, can someone help me please?
So I have noticed that the server, after reboot in general, never came back online.
We sent a support ticket to hetzner thinking that it has to be a hardware problem, because we format the machine, no updates nothing, reboot, and server offline. They replied to us that Debian 12 has software raid degradation problem. Whatever that means. I have a ryzen 5 3600 there with software raid and i don't have this issue.
The truth is that I have installed Debian 12 clean and proxmox 8 clean. I have installed proxmox ve from Debian 12 as last resort but always the same thing. We reboot and server is unreachable. I didn't install Debian 11 or Proxmox 7.4 since I am not in favor of outdated software/os.

I would like a source please if there is such a problem as hetzner replied and what workarounds we can do.
1 solution is always to use robot to reset the server after each reboot but this is not a professional solution.

One more thing, I have followed different guides but I didn't achieve the endgoal, example this guide
As I have posted in the original post, I would like to make a VM with pfsense/opnsense/sophos/younameit and add to that the /29 subnet for firewall purposes.
In that guide it says: The guest's configuration is much simpler than the host's one. The guest has to use the pointopoint option in order for IPv4 addresses to reach the host system.
So how do I add pointopoint on those firewall os?


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