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TIL: Getting a first-gen Raspberry Pi online is the hard part (Garage Door Project, Part 2/5)

raspberry-piwifinetworkingsshtil

Series: Opening my garage door with my phone — Part 2 of 5 Learned: 4–7 July 2026

In Part 1 I decided a Raspberry Pi would host the API and talk to the Arduino over USB. The Pi I had is a first-generation Model B: no Wi-Fi, two USB ports, and a very old Raspbian on the SD card. Getting it reachable on my network turned into the longest chapter of the whole project.

1. Attempt one: a USB Wi-Fi dongle

Buying advice I got (and would repeat):

  • A Pi 1 needs a USB Wi-Fi adapter. Look for “Linux compatible” or “Raspberry Pi compatible” and a chipset with in-kernel drivers.
  • Prefer a small 2.4 GHz “nano” adapter. The Pi 1 can’t use 5 GHz speeds anyway and has very little power to spare on its USB ports.
  • Use a good power supply and, ideally, a powered USB hub.

What actually happened:

  1. wpa_cli -i wlan0 reconfigure failed with Failed to connect to wpa_supplicant - wpa_ctrl_open: No such file or directory.

  2. sudo raspi-config had no network options at all. That’s the tell that you’re on a very old Raspbian (Wheezy/Jessie era). Back then Wi-Fi was configured in /etc/network/interfaces:

    auto wlan0
allow-hotplug wlan0
iface wlan0 inet dhcp
    wpa-ssid "YOUR_SSID"
    wpa-psk "YOUR_PASSWORD"

  3. Still nothing, so I checked whether the hardware was even seen:

    lsusb               # only the internal hub + Ethernet chip, no dongle
dmesg | tail -n 20  # the real story

What I learned from dmesg: the dongle was detected for a moment (a Realtek chip, driver r8188eu), then two things went wrong:

  • the firmware file rtlwifi/rtl8188eufw.bin was missing (error -2), and
  • right after, USB disconnect, most likely the Pi 1’s USB port browning out when the radio powered up.

So: missing firmware and not enough power. Two problems that look like one.

TIL: lsusb tells you if the hardware is there now. dmesg tells you what happened when you plugged it in. Read dmesg first.

2. Attempt two: give the Pi a cable instead

Instead of fighting the dongle, I put a Wi-Fi range extender with an Ethernet port next to the Pi. The extender joins the home Wi-Fi and the Pi just sees a normal wired network.

Setting up a TP-Link extender, three ways:

  1. WPS: press WPS on the router, then within two minutes press WPS/RE on the extender.
  2. TP-Link Tether app
  3. Browser: join the extender’s own Wi-Fi and open http://tplinkrepeater.net (or 192.168.0.254).

Configure it next to the router, then move it roughly halfway to where you need the signal.

3. “The lights are on but nobody’s home”

The Ethernet LEDs on the Pi were lit, but the Pi never got an IP address. Things worth checking:

  • The extender must act as a bridge: the main router hands out IP addresses, not the extender.
  • Compare subnets: if the Pi and your laptop aren’t in the same 192.168.x. range, they can’t talk.
  • Plug the Pi directly into the router for one minute. If it gets an IP there, the extender is the problem; if not, the Pi is.

In the end the quickest fix was a fresh SD card image.

4. Fresh install, still “Connection refused”

I flashed a new image with Raspberry Pi Imager and used its settings (gear icon) to enable SSH and create my own user. The Pi booted and showed its IP. SSH said Connection refused.

What I learned about debugging SSH, in order:

  1. ping the Pi. If ping works, the network path is fine and the problem is the SSH service or the address.
  2. ssh -v user@ip shows where the handshake stops.
    • Connection refused → nothing is listening on port 22 at that address.
    • Permission denied → SSH is fine, credentials aren’t.
  3. Check the IP really belongs to the Pi in the router or extender client list. After re-imaging, it may have a new one.

  4. Clear the old fingerprint if you’ve connected to that IP before:

    ssh-keygen -R 192.168.x.x
  5. Give the first boot a few minutes, because it generates host keys.
  6. If you can’t get in at all: put an empty file named ssh in the boot partition of the SD card, or borrow a keyboard and run sudo systemctl enable --now ssh.

Also: you can’t SSH to a MAC address. You can use the MAC address in your router to find, or permanently reserve, the Pi’s IP.

Eventually I was in. 🎉

Takeaways

  • On a Pi 1, USB Wi-Fi is a power and driver problem. A powered hub plus the right firmware package, or skip it entirely.
  • An extender with an Ethernet port is a neat way to bring a wired-only device onto Wi-Fi.
  • dmesg > guessing.
  • For SSH: ping → ssh -v → confirm the IP → clear known_hosts.

Next up: the Python bridge that turns an HTTP request into a relay click.