Hey I’m writing this because my initial attempt resulted in my router not accepting any connections until it was rebooted so I thought I had to see what the community had to say about my idea.
I have two networks in my home, the outer most router is an APU board running obsd and has subnet 10.0.1.0/24 while the Turris Omnia is a client in that network so its wan interface has 10.0.1.2 and its wifi clients use another subnet called 10.0.2.0/24.
I want to create a new wifi network that is bridged to the wan network. So that wifi clients who connect to the new wifi network get dhcp from my LAN and are assigned IP-address in 10.0.1.0/24 just like any other client I connect to one of my switches.
So I tried creating a new interface under Interfaces and bridged it to wan. At this point I noticed no other requests were working in my browser and DNS had stopped working from the CLI.
I was going to create a wireless interface and bind it to the newly created interface but there was no point as I had lost access to the internet so clearly I was doing something wrong with the first step. I deleted all my changes and rebooted omnia, access to internet was restored.
Haven’t tested it, but I suspect that you just want to edit existing wan interface. So approach would be to add another SSID to your wifi. During that you create/name new interface (in this sense interface means real interface not luci interface). Then you can edit wan interface (luci interface meaning) and in hardware section switch it to bridge and add your new wifi interface (meaning real interface).
Edit: Just small explanation about that interface madness. Luci and basically network configuration of OpenWRT creates abstraction on top of real network interfaces (let’s call them links). What is called as interface is basically one network with dedicated ip. If you try to create bridge then it puts multiple links together to one interface. So although it’s possible to create interface for every link it wasn’t indented as a way to setup bridges. If you want to have bridge over multiple links then you should use one interface and just enable bridging for it. Using two interfaces probably allows you to configure multiple ip ranges and multiple firewall zones and that is mostly likely not what you want to do unless you want to have a headache.
I had more or less a similar problem. I just wanted to use wan (behind an outermost router) as failover to LTE connection.
At first i added wan interface in lan firewall zone but after each update most of the times this was breaking.
Then I created a new firewall zone and i am using Masquerading & MSS clamping except for the lan subnets (I accept Input Output & Forward between lan and this interface). This works (but I have not figured out yet why it is not working for the Lxc containers).
I hope this is of some use to you.
If you manage to implement your setup, please report back here with your solution.