What kind of WiFi/network setup do I need?

I've got a problem with my network setup that at first seemed pretty easy to solve, but the more I read online the more confused I get ...

I have a modem which pretty much acts as the "center of the network": DHCP server + router + WiFi AP. If only WiFi was required, I could already live with this single device as the coverage is very good in every room of the building. However, I also do have a few network devices that can only be connected to the network via Ethernet (no WiFi), like Philips Hue Bridge first generation. Unfortunately, all of those devices are too far away from the modem to simply plug them in there ...

My first attempt of a solution was to (mis)use a TP-Link TL-WA701ND_v2 running on LEDE as some kind of "WiFi AP-bridge" (if that is the correct term), which would be a WiFi client to the modem and an AP to all WiFi network devices. A simple switch that I connected to the only Ethernet Port of the TL-WA701ND_v2 would provide the non-WiFi-capable devices with network access. This solution did actually work, however, it required having two different WiFi networks (one from the modem, another from the TL-WA701ND_v2). And for some reason that I don't understand, both modem and AP had to have DHCP enabled for this setup to work. Now, while this setup, albeit everything but pretty in its design, did work, unfortunately the TL-WA701ND_v2 could only provide very poor WiFi coverage compared to the modem WiFi. So I got frustrated soon and started looking for another, better solution ...

And that's where I am right now, not quite sure what I actually need, and hoping you guys can help me.

What I want is this: https://wiki.openwrt.org/doc/recipes/bridgedclient One big network, including the modem and the TL-WA701ND_v2. Both should be APs (same SSID, security settings, etc.), but only the modem should be a DHCP server. And devices, obviously, should connect to whichever AP is providing the stronger connection.

^^ Problem is, I can't seem to go with that solution since none of my devices support the legacy WDS (for Atheros chipset).

What I believe I can have is that: https://lede-project.org/docs/user-guide/relay_configuration

^^ Problem is, as far as I understand this setup, while the WiFi would form one big subnet, I would "lose" the LAN port on the TL-WA701ND_v2, effectively putting all devices connected to the switch (which is connected to that LAN port) in another subnet?!


So, what solution do I actually need to get what I want?

PS: Please let's try to find one that doesn't involve buying new devices, and instead uses the ones I already have.

Any help is greatly appreciated! Many thanks!

What you need is exactly the relay-based configuration; and you will not lose the LAN interface, wired clients will be "bridged" to the main network.

I would make it first a normal client bridge. Dont understand your statement about losing the LAN interface. You loose this anyway cause you have to connect it to your switch (which looses a LAN port as well) . All the wired connections will use your WA701 to connect wirelessly to your primary router/modem.

Once you have this up and running just add a second "virtual interface" which is AP. Even you say this would not be needed since your primary wifi is good enough.

I'm a bit confused with all the different terms but I believe that I already have what you are suggesting ...

Right now the TL-WA701ND_v2 is a wireless client connected to network "A" from the modem, and at the same time also works as an AP providing network "B" (wireless and wired via the switch). And this two-subnets situation is exactly what I wanna get rid of.
There should be just one big subnet with two APs (modem and TL-WA701ND_v2) and ALL devices should be able to connect to each other no matter to which AP they are connected and regardless of whether they are wireless or wired.

As for my statement about "losing" the LAN port: I was assuming that the relay solution would put the LAN port in a different subnet, thus creating a second subnet parallel to the wireless subnet. Not what I need! But apparently that assumption was wrong anyway.

I think I'll give the relay solution a try and see how it turns out ...

Simulating a bridge with relayd was indeed the right solution. I just tried it and everything works perfectly fine now.

I even added a second TL-WA701ND_v2 with a switch connected to it, which means I have three APs now, all within the same subnet. Also, perfect WiFi coverage in the whole building and the option to connect as many Ethernet-only devices to the subnet as my switches have ports.