RaspberryPiHotspotIfNoWifi

Automatically create a WiFi hotspot on your Raspberry Pi if it fails to connect to any of your preferred WiFi networks. Works on Raspbian "Bookworm" and Raspberry Pi Zero 2 W (should work on other models as well).

Features

• Tries to connect to up to three specified WiFi networks (each with its own password).
• If none connect, automatically creates a WiFi hotspot using NetworkManager.
• Designed for headless setup (no monitor/keyboard required).

Setup Steps

1. Install Raspbian: Flash Raspbian "Bookworm" to an SD card. Enable SSH and configure a username/password. Raspberry Pi Imager
2. Boot and SSH: Insert SD card into Pi, boot, and wait ~10 minutes for setup. Find its IP from your router or try:

   ssh username@hostname.local
   # or
   ssh username@192.168.1.xxx

3. Download the scripts:

   sudo curl -L https://raw.githubusercontent.com/PeterJBurke/RaspberryPiHotspotIfNoWifi/refs/heads/main/check_wifi.sh | sudo tee /usr/local/bin/check_wifi.sh > /dev/null  # Overwrites if file exists
   sudo chmod +x /usr/local/bin/check_wifi.sh
   sudo curl -L https://raw.githubusercontent.com/PeterJBurke/RaspberryPiHotspotIfNoWifi/refs/heads/main/check_wifi.service | sudo tee /etc/systemd/system/check_wifi.service > /dev/null  # Overwrites if file exists

4. Edit check_wifi.sh: Open the script and configure your WiFi SSIDs and passwords, and your hotspot SSID/password.

   sudo nano /usr/local/bin/check_wifi.sh
   # Set DESIRED_SSID1, DESIRED_SSID1_PASSWORD, etc.
   # Set HOTSPOT_SSID and HOTSPOT_PASSWORD

   After editing in nano, press Ctrl+X to exit, then type Y to confirm saving, and press Enter to keep the default filename.
5. Enable the service:

   sudo systemctl enable check_wifi.service
   sudo systemctl start check_wifi.service

6. Reboot:

   sudo reboot now

7. Usage:
   • If Pi connects to your WiFi: use as normal.
   • If not, it will create a hotspot (default IP: 10.42.0.1). Connect to this from your device and SSH in:

     ssh username@10.42.0.1

How It Works

• The script checks if the Pi is connected to any of the three specified SSIDs.
• If not, it tries to connect to each SSID in order, using its password.
• If all fail, it creates a hotspot using NetworkManager.

Troubleshooting

• NetworkManager must be installed and manage your WiFi interface.
  • Install with: sudo apt install network-manager
  • Disable dhcpcd if needed: sudo systemctl disable dhcpcd
• Your WiFi adapter must support AP (Access Point) mode.
• Check script logs:
  • The script logs to stdout/stderr. If run as a service, check logs with:

    sudo journalctl -u check_wifi.service -f

• Check NetworkManager logs:

  sudo journalctl -u NetworkManager -f

• Check WiFi status:

  nmcli device status
  nmcli connection show
  nmcli device wifi list

• Debug connection attempts:
  • Try connecting manually:

    sudo nmcli dev wifi connect "SSID" password "PASSWORD" ifname wlan0

• Hotspot doesn’t start?
  • Make sure no other connection is active on the WiFi interface.
  • Try bringing down existing connections:

    sudo nmcli con down id <connection_name>

  • Delete old hotspot profiles if needed:

    sudo nmcli con delete id <connection_name>

• Permissions: Script must be run as root (sudo).

Customization

• Change the number of SSIDs by editing the script and adding/removing DESIRED_SSID/PASSWORD pairs.
• Adjust hotspot SSID/password as desired.

Credits

• Inspired by community solutions for Raspberry Pi WiFi fallback and hotspot automation.

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If you encounter issues, please open an issue on the GitHub repository.