Cannot set up WiFi on Raspberry Pi Zero W running Stretch

Question

I have been trying to connect to my wireless network for several days now with my Raspberry Pi Zero W running Stretch (2017-08-16 release). I have read many threads on how to setup wifi, including the official guidelines from Raspberry Pi's website and this post but cannot figure out what I am doing wrong. I can see my wireless network using sudo iwlist wlan0 scan. Using sudo ifup wlan0 returns:

wpa_supplicant: /sbin/wpa_supplicant daemon failed to start
run-parts: /etc/network/if-pre-up.d/wpasupplicant exited with return code 1
ifup: failed to bring up wlan0

Here are the contents of my wpa_supplicant.conf file:

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1

Network={
ssid="nowan"
psk="12qwaszx"
key_mgmt=WPA-PSK
}

Here are the contents of my /etc/network/interfaces file:

# interfaces(5) file used by ifup(8) and ifdown(8)

# Please note that this file is written to be used with dhcpcd
# For static IP, consult /etc/dhcpcd.conf and 'man dhcpcd.conf'

# Include files from /etc/network/interfaces.d:
source-directory /etc/network/interfaces.d

auto lo
iface lo inet loopback

iface eth0 inet manual

auto wlan0
allow-hotplug wlan0
iface wlan0 inet manual
wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf

allow-hotplug wlan1
iface wlan1 inet manual
wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf

Any advice/help would be greatly appreciated!

Answer 1

To get the WiFi working on a Pi Zero W only requires minimal config for Raspbian Stretch. The only file you need to modify is /etc/wpa_supplicant/wpa_supplicant.conf and this file needs to contain your WiFi network's SSID and password - which you add after the initial lines (the first 3 lines) that are already there so the file should look like something like this (country might be different for you):

country=GB
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
network={
  ssid="mywifinetworkname"
  psk="my wifi password"
}

You don't need the /etc/network/interfaces file at all - The default setup in Raspbian Stretch does not contain an interfaces file. So just delete/move/edit the /etc/network/interfaces file if you have created one.

This just works as the wpa_supplicant service will just start up automatically if it finds its config file (/etc/wpa_supplicant/wpa_supplicant.conf) and connect the WiFi interface (wlan0) to the network. The default DHCP client dhcpcd attaches to all interfaces so it will then obtain an address.

If you want to assign static IP addresses or do other fancier network config you may then need to create an interfaces file or modify the /etc/dhcpcd.conf file.

And if you want the device to be accessible via ssh then you can create a file ssh in the /boot directory (remembering that if you're doing this to the micro SDcard on another machine - the boot dir is mounted on the first partition e.g. /dev/sdb1, and root would be on /dev/sdb2):

sudo touch /boot/ssh

Or if you're logged in just use systemctl:

sudo systemctl enable ssh.service

Answer 2

You're most of the way there, I'll include full steps from a fresh install to my answer to help out other users. But this appears to be a bug in Stretch.

Make sure your wpa_supplicant.conf is in place then do

sudo nano /etc/network/interfaces

and add

allow-hotplug wlan0
iface wlan0 inet manual
    wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf

to the end of the file. Then do

sudo systemctl enable wpa_supplicant.service

Then reboot

Answer 3

Be aware that wpa supplicant is no exception to Linux rules: it is case sensitive!

In your wpa_supplicant.conf file, network={ is written with a capital N

That is already enough to make the parsing process fail...

Answer 4

Setting up pimoroni optocam with motioneyes OS I came upon this problem.

Fixed it by:

1. Editing the wpa_supplicant.conf I'd created using Notepad++ and in the Edit menu, changing the EOL setting to Linux.
2. Copying wpa_supplicant.conf to my PC desktop
3. Using Win32 Disk Imager to re-image the SD card from motioneyeos-raspberrypi-20180224.img
4. Copying the wpa_supplicant.conf from my PC back onto the boot of the SD card
5. Inserting into Pi zero and booting up

I think the problem was that I'd put incorrect wifi details into the wpa_supplicant.conf the first time I'd tried to boot up, and the Pi zero was using these details all the time. Even if I changed the wifi details in the wpa_supplicant.conf on the boot of the SD card, it made no difference. The only way to fix it was a clean image.

Someone should really make this work better. It's really confusing for noobs. Hope this helps someone.