I have Linksys WRT54GL router with OpenWrt Backfire 10.03.01. I'll call it a secondary router.

Currently it provides LAN connection to a location that has poor WiFi connectivity to the main router. The main router sits in the 1st floor, and the secondary router is placed in a location on the 2nd floor where it can still get a reasonable strength WiFi signal to the main router. The clients on the 2nd floor are connected directly to the secondary router with Ethernet wires. There is nothing plugged in the secondary router's WAN socket.

This setup lets me to have the same subnet (192.168.1.x) for both floors. The downside is that the secondary router's WiFi is used to connect to the main router and so it is not available to the 2nd floor clients.

Here are some screenshots of the LAN/WAN interfaces and WiFi setup on the router.
https://drive.google.com/drive/folders/ … sp=sharing

Now, I am about to drill a hole between the floors and pull through an Ethernet cable. The idea is that I'd connect this cable to one of the main router's LAN ports and the other end to the secondary router's WAN port.

The setup I am looking for is that would still let me use the same subnet (DHCP served from the main router, the IP gateway to the main router), but now I could make both wired and wireless connections to the secondary router. Ideally, it would be preferable that the WiFi network name/pwd is the same and the client's can move from the 1st floor to the 2nd floor without interrupting connection.

The problem is I have no idea how to make that configuration or even if it is possible. I managed to almost brick my router in the numerous attempts, before I had to admit to myself that I have no idea what I am doing.

https://openwrt.org/docs/guide-user/net … figuration is a good starting point. It specifically describes using the WiFi to make the connection to the parent network, sharing the result over Ethernet (which sounds like your existing setup).

You want to adapt it so that the connection to the parent network is made via Ethernet, and the result is then shared over Ethernet and WiFi.

Off the top of my head, here's how I'd approach it:

• Adapt the wiki article's instructions to suit your environment

• Make sure the LAN interface is a bridge between the LAN Ethernet sockets and the WiFi

• Set the WAN interface protocol to be relayd

• Don't bother creating a new "wwan" interface

• Connect the WRT54GL to the parent network via the WAN interface and some CAT5/CAT6.

The above is not an exhaustive list of all steps (and might also not be entirely accurate). But it's a starting point of the list of the things I'd be looking for if I was doing what you're trying to do.

To add to the above: I can't remember Backfire's factory default configuration (it's been so long since I last saw it). But I do know LEDE 17.01.4's factory default configuration:

• WAN is a DHCP client

• LAN is a DHCP server with a static address

So switch off the DHCP server on the LAN interface, and set WAN to relayd. Or an equivalent set of steps which is suitable for Backfire.

When you have a wired LAN backbone your secondary router(s) should be configured as "dumb APs".  No routing, no DHCP server, just a bridge from ethernet to wifi.

You can reconfigure the WAN port so it is in the LAN network, and have 5 switched LAN ports.  This is optional, if you don't do it just make sure not to plug anything into the WAN port.

You can use the same SSID and encryption password so then you only have to configure one network in the client, and it should connect to the strongest one (this behavior is entirely client dependent though).  The routers should be set to different radio channels.

(Last edited by mk24 on 14 Mar 2018, 15:15)