Initialize a headless RaspberryPi connected by Wifi, 100% from Windows

Question

This works to initialize a headless RaspberryPi connected by Wifi (no screen/keyboard never needed attached to RPi):

1. Get a Raspbian Stretch Lite from https://www.raspberrypi.org/downloads/raspbian/ and write it to the micro SD card with Win32diskimager or Etcher

2. Add an empty ssh file in the boot partition

3. Boot on Linux (or boot a Linux VM on Windows), or use Linux File Systems for Windows in order to edit /etc/network/intefaces and add:

   auto lo
   iface lo inet loopback
   
   allow-hotplug wlan0
   iface wlan0 inet dhcp
   wpa-ssid "MyRouter"
   wpa-psk "92dc84ee7e7032be9142828023912e77"
   
   allow-hotplug eth0
   iface eth0 inet dhcp
   

This works, I've done it many times in the past years.

Problem: for a Windows user, step #3 is not very convenient. An alternative would be to initially connect via ethernet cable, SSH with putty, and edit /etc/network/intefaces with nano, but it's not very handy too, because it requires to connect the RPi to the router with a cable.

Question: which method would allow to initialize a headless Raspberry Pi, including the Wifi ssid/password setting, 100% from Windows?

I see a few options:

• A) Would there be a way, on a fresh Stretch Lite install, only by modifying files in the boot partition (accessible from Windows), to configure Raspbian to use a file intefaces in the boot partition instead of the usual /etc/network/interfaces ?

• B) Would there be a way to put a script copyinterfaces.sh in the boot partition:

  #!/bin/bash
  sudo cp /boot/interfaces /etc/network/interfaces
  

  that would be launched on the first boot of the RPi? Then we could put both the intefaces file (written in the boot partition - easy from Windows) and the copyinterfaces.sh file in the boot partition, and during the first boot, the boot partition's interfaces file would be copied to /etc/network/interfaces

• C) another idea?

Once again, the goal is: to be able to set up a headless RPi connected by wifi, without using a keyboard/screen/ethernet cable ever, 100% from Windows, so that we can SSH with putty and never have to boot Linux (some users don't have any Linux installation), and never have to use an ethernet cable.

Answer 1

See Headless Raspbian WiFi Setup in How to set up networking/WiFi

Specifically Raspbian checks the contents of the boot directory for a file called wpa_supplicant.conf, and will copy the file into /etc/wpa_supplicant, replacing any existing wpa_supplicant.conf file that may be there. The file in the boot directory is then removed. This can be used to enable headless setup.

NOTE the etc/network/intefaces you listed is obsolete and is not needed. Even in 2015 it would have been poor practice but it has been replaced by dhcpcd which is far more robust.

Answer 2

Additional information to the accepted answer:

1. Write the Raspbian Stretch Lite image to the SD card

2. Create a ssh empty file in the boot partition

3. Create a wpa_supplicant.conf file in the boot partition containing:

   ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
   update_config=1
   country=FR
   network={
     ssid="MyRouter"
     psk="the_password"
   }
   

4. Boot the RPi and connect it via SSH (for example with putty.exe from Windows). It works, 100% from Windows!

Important note: I've tried with only a wpa_supplicant.conf file containing only:

network={
  ssid="MyRouter"
  psk="the_password"
}

but it did not work; the other lines (update_config...) seem mandatory.