Get internet from second router over LAN

I personally would just set stick to one lan.

Right now I have these 3 devices:

  • lan (br-lan), green, Protocol: Static address, Device: br-lan, DHCP server enabled
  • wan (dsl0), red, Protocol: DHCP client, "Error: Network device is not present"
  • wan6 (Alias of "wan"), red, Protocol: Alias Interface (DHCPv6 client), "Error: Network device is not present"

So since on the laptop I am connected to the UI over WIFI is the lan Interface actually WIFI?
Meaning I would need to make the wan Interface able to receive the input from the LAN cable coming from the FritzBox?

I think first I would like to try it with the hardware I have now if possible.

Those are Interfaces. Click the Devices tab near the top of the Network-Interfaces page to see the bridge br-lan and other devices.

I would recommend continuing with setting up lan->wan routing as most all the instructions you'll find for a router VPN client assume that is the base configuration.

If you are connected over Wifi you will be connected to the bridge device. A network bridge is simply a virtual switch that connects physical and virtual devices together. To connect OpenWRT to the bridge device you have what are called interfaces. lan, wan and wan6 are all interface devices that allow OpenWRT to present itself to the bridge so that you can access it. To boil it all down your physical lan ports and your wireless access point are all in the same bridge so they can see each other at a data link (mac) level.

I really don't know anything about FritzBox but from what I can find it is german thing. My guess is that it has a way to set a static IP from the settings. I would first connect your device to the Fritzbox and then set a static IP on your machine. Once you have a static IP then set a static IP on the fritzbox. You should set the IP to something bigger than 192.168.1.150 such as 192.168.1.200. Once you have the static IP I would reset OpenWRT so that it is back to the default of 192.168.1.1/24. Once that is done connect your OpenWRT device to a switch and then hook up the FritzBox. In OpenWRT set the gateway for lan to be the IP address of the FritzBox. You can delete the wan and wan6 interface since it isn't used.

I hope that helps somewhat. In the setup above outgoing traffic is first sent to the OpenWRT device which then sends it to the FritzBox where it goes out to the internet. I have never set anything up like this before so I could of skipped a step.

Sorry for the delay again. Had to take a sick leave and some family stuff.

Those are Interfaces. Click the Devices tab near the top of the Network-Interfaces page to see the bridge br-lan and other devices.

Right, sorry for the confusion. I think I missed that tab before.
In there I have

  • br-lan, Type = Bridge device
  • dsl0, Type Network device
  • lan, Type Network device
  • eth0, Type Network device, greyed out
  • phy0-ap0, Type Network device, greyed out
    Each has a blue Configure button and an Unconfigure button on the right. But not sure what to configure where...

@Darin755 I have some pc knowledge but this is still a bit confusing. The FritzBox UI is much more intuitive. To visualize what I want, here's a picture:

I'm not sure resetting the OpenWrt router again would help since I just did that last time and then I only changed its IP to 192.168.2.1 and enabled Wireless with WPA2 and a password from what I remember. Still dont have a hardware swtich and not sure I need one. I am willing to see how performance is with a software switch before I buy more hardware.

Since the Fritz!Box has got only the DSL Port and 1 LAN Port,
this won't work as you like.
Do you really need the FB7412? You could just connect the OpenWrt router to the Wall box modem (what kind of device is this?)

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No, the FritzBox in that image is a different one with 4 LAN ports. The FB7412 is the one I put OpenWrt on.
Not sure about the wall box modem, no description on it.
The idea with chaining them is to have the FB as a additonal firewall.

I had to restart the OpenWrt router earlier because couldnt access the UI over wifi. Same as earlier, had to connect with LAN to laptop to login, then put LAN back to FB but WIFI didnt work anymore and had to do it all a 2nd time. Does that mean there is an IP assign conflict somewhere?

Ah, that wasn't clear to me. Thanks for clarification.

That depends...
I presume, the 'big' Fritz!Box has WLAN enabled.
You have got different SSID's on the FB and your OpenWrt router?
Regarding your picture, everything is on the same network.
There's no additional routing involved?
And which device is the acting DHCP server for this network?
Or do you use only static IP addresses?

I presume, the 'big' Fritz!Box has WLAN enabled.

For now. Might disable it later when the OpenWrt one runs.

You have got different SSID's on the FB and your OpenWrt router?

That's just the WIFI name, right? Then yes.

There's no additional routing involved?

Not that I'm aware of.

Or do you use only static IP addresses?

In the FB when I check the device at the connected LAN port in the network overview it has "Always assign the same IPv4 to this device" so that looks static to me, right?

Other than that in the OpenWrt router under Network > Interfaces > lan > Edit there is Protocol = Static address as well.

And which device is the acting DHCP server for this network?

Not finding this atm. Is there a command I can run on the connected laptop to find out?

Edit: I guess since I can connect to the WIFI of the FB this means it acts as the DHCP server? Then with the OpenWrt router connected to it what settings do I need to change there to allow it to get internet from the FB?

In this case, yes.

That depends, if you want to use the 7412 as a router or a dumb AP.

In AP mode, every device (the FB and the devices connected to it and the 7412 and the devices connected to it) are on the same network.
In router mode, the devices on the FB and your 7412 are on different networks.
It's up to you to decide, how to set it up.
For dumb AP mode, you should consult this.
You will have to disable DHCP on the OpenWrt device and use the (already active) from the FB.

In router mode, the 7412 will be the DHCP server only for the devices connected to it via WLAN.

Thanks for the link! I'll try reading through it tomorrow if I have the time and energy.
An AP sounds simpler I guess instead of having to manage an extra network? The main goal is to put Wireguard on there. Does this make a difference for which option to pick?

Not really. Both has pro's and con's.

I don't know.
I haven't tried to put it on an AP.
For this, you might start a new thread.

There is no point in creating an additional Firewall

So did you figure out what you needed? I modified your diagram a bit to try to show how the network would be designed.

I found this article about putting the Fitzbox device in bridge mode. This is probably what you want.

https://support.edpnet.net/en/support/installation-and-usage/internet/manage-fritz!box/how-do-i-configure-my-fritzbox-in-bridge-mode.html

https://openwrt.org/docs/guide-user/network/wan/isp-configurations

Sorry, didn't have much time again this week. Between college classes, part time job, gym, family and other stuff it's though to find a few hours in one block so I can take my time...

Not sure bridge mode will be possible. Technically the FB belongs to my flat mate so I can't make too many changes on it. Part of the reason why I want to set up this OpenWrt router as my own.

I gave the guide for the dumb AP a quick scroll over and it looks good I think in terms of the detailed instructions I am looking for. But I still need to apply it.

One thing I am not sure about is at the start:

This is often called a “dumb AP” since it will not perform duties such as routing, firewall, DHCP, or DNS, as these are performed by the router or other device.

Is it still possible to put Wireguard in between the incoming LAN and outgoing WIFI like I want with this? Or is it part of the routing and then not available?

A dump AP is running in layer 2. To do anything more advanced you need the device to work in layer 3. That means that it becomes the gateway and handles IP routing.