HOWTO [Guide+Code]: Running multiple APs + Auto-Connect to WiFi

[moryoav]

Hi everyone,

I’ve just published a new GitHub repo that bundles everything I’ve learned getting multiple APs and a client uplink working on a Raspberry Pi running RaspAP:

👉 https://github.com/moryoav/raspap-multi-ap

What it is
A turnkey setup consisting of two shell scripts plus a sample crontab that:

1. Boots up with two separate hostapd configs (e.g. 2.4 GHz on wlan0, 5 GHz on wlan1).
2. Enables IP forwarding and NAT so your AP clients route out through a third interface (wlan2).
3. Auto-connects wlan2 as a station to your upstream Wi-Fi network via wpa_supplicant.

Why I created it
I wanted a reliable way to run dual-band APs and still provide internet access via a USB dongle. So that I have 2 blazing fast USB WiFi dongles, one to connect to the internet and one to provide a 5Ghz AP (while the onboard WiFi provides 2.4Ghz AP as backup).
The semi-official guide here was not enough for me. One reason was that it didn't include the information I needed to get it to work following a reboot (hence adding it to cron in my tutorial), and also lacked some other things I needed to get the routing to work.

Power-draw gotchas
On a Pi 4 the four USB ports share only ~1.1 A total. Once you dedicate one port to your SSD (e.g. in an Argon One case that I'm using), you simply don’t have enough juice left for two high-speed Wi-Fi adapters. I ran into dropped connections until I finally switched to a powered USB hub which solved all my issues. You’ll find a detailed explanation (with current-budget numbers) in the USB Power Considerations section of the README.

Two scripts in one repo
The two scripts are seemingly unrelated. One allows you to set up 2 APs, the other just automates connecting to the internet after boot (using wlan2, the 2nd WiFi adapter). You can just use one of them, according to whatever you need. In my case I wanted both, but this is not a requirement, just convenience (for me).

All code is released under the MIT license, so feel free to fork, modify, redistribute, or just dive in and give feedback.