[SOLVED] How to do VLAN networking with virtual OPNsense

Rowe

Member
Sep 14, 2019
16
0
21
Hello.

I am trying to set up an OPNsense box running as a VM in proxmox. This OPNsense box needs to be my gateway/firewall for all of the VLANs on the LAN. I am however a little confused on a couple of things.
Up until now I have tried to set this up with a single vlan aware linux bridge. I have not had success on getting this up an running. The problem here lies in the network configuration on the virtual machine. I want to trunk all of my VLANs through to the firewall, therefor I leave the 'VLAN tag' field empty in the network configuration of the VM. I just cannot seem to get this right, when I create the VLANs on the firewall itself. The connection sometimes work, and sometimes just drops.

Because of this problem, I have been searching the internet for a solution to this. Here some are suggesting that you create a subinterface for every vlan on the host itself. This should harden the security, since the VLAN segregation will happen on the host itself. I do not know if this is true however. Please correct me if this is wrong.

I guess that boils it down to my original questions:
1. Is it smarter/easier to create a sub-bridge for every VLAN, and then just assign those interfaces to the virtual firewall?
2. Or should I go with a single bridge, and try to get that working?
3. Will separate bridges be more secure?
4. I know that the theoretical internal switching speed is 10Gb when using the same bridge between VMs/containers. Will it go down to 1Gb if using separate bridges?

Just some short info on my setup:
WAN network interface is a PCIe card, that has been assigned directly to the VM.
The firewall hardware, has been assigned according to the requirements found on OPNsense wiki.
 
After my post I played a bit around with adding the trunk bridge to the VM multiple times, and with only one VLAN tag. I figured that there was no need for a VLAN setup in OPNsense when that is possible to do on the host itself.
I am going to mark this thread as solved, since it works like I want it it. Please feel free to leave a comment if you have anything to say (good/bad) about this setup.
 
I had a similar challenge.

In the end you need to mark the bridge as VLAN-aware, that's about it.
Mind you, it can make sense to create vlan-enabled bridges, and I eventually did.
I guess it was just me who could not figure out how to configure it correctly.
 

About

The Proxmox community has been around for many years and offers help and support for Proxmox VE, Proxmox Backup Server, and Proxmox Mail Gateway.
We think our community is one of the best thanks to people like you!

Get your subscription!

The Proxmox team works very hard to make sure you are running the best software and getting stable updates and security enhancements, as well as quick enterprise support. Tens of thousands of happy customers have a Proxmox subscription. Get yours easily in our online shop.

Buy now!