Cannot get WiFi to work on PI 3 running stretch

Question

I have 2 identical rpi 3 devices. Both are running the same version of OS, namely "stretch" version 9 (from the same source). They have slightly diverged via upgrades and updates.

On one I can use wifi-no problem. On the other I cannot.

All configurations files are identical (as far as I can tell). In particular, my wpa_supplicant.conf looks like below.

There are two anomalies I've detected on the problematic pi:

1. After every reboot ps -e | grep wpa lists two processes called "wpa_supplicant", while on the "good" pi only 1 is listed.
2. The ssid, I'm trying to connect to, is indeed listed when I click the icon on the toolbar. However, despite the fact that an entry exists in wpa_supplicant.conf, I get prompted and asked to enter the "Pre Shared Key", which I understand is the password. I notice that once I enter it, the file wpa_supplicant.conf is overridden, with the same content it had before.

In addition, I've installed wpa_gui. It provides some more information in (what is referred to as) the event history of the tool. First, by default, the adapter is set to "p2p-dev-wlan0". So, I switch to wlan0. Then, I get:

ctrl-event-ssid-reenebled id=0 ssid="my-ssid"
trying to associate with <some numbers> (sside="my-ssid" freq=...)
ctrl-event-assoc-reject status code=16
ctrl-event-ssid-temp-disabled id=0 ssid="my-ssid" auth_failure

and my wpa_supplicant.conf:

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

network={
    ssid="my-sside"
    psk="my-passowrd"
    proto=RSN
    key_mgmt=WPA-PSK
    pairwise=CCMP
    auth_alg=OPEN
}

Any help is appriciated...

Answer 1

wpa supplicant is such a pain in the back. They made it so difficult to connect to WiFi and then re-connection does not work either.. or setting it up is really weird.

It may take a little bit more space on your card but I love using wicd-curses.

sudo apt-get install wicd-curses

start it up

If you get a message saying no networks detected press P (must be capital so use [SHIFT]p) and type in wlan0 in the wireless interface field and press F10 to save.

1. R to refresh the list.
2. Use the cursors on the keyboard to navigate up and down the list
3. Press right to configure the wireless connection
4. Press down a few times and check "Automatically connect to this network"
5. Press down a few times again and type in your password in the key field
6. Press F10 to save

You might have to press C to connect to the access point. If you were wired that will most likely kill the LAN interface and bring up wireless.

It is also manages the connection so it will reconnect to any configured wireless access points if it drops out for whatever reason.

I tested plugging out the WiFi adapter and plugging it back in. It takes about 60~90 seconds but it will connect back to WiFi (I think the LAN must be unplugged though)

Hope it helps!

Answer 2

Is the image a desktop image? If so connect your Pi to your router and find the IP address of it on the routers webpage. Then ssh into it. Enable VNC in raspi-config. Download tight vnc onto your computer and use it to connect to wifi.

Answer 3

I am dubious of the fact that there are 2 copies of wpa_supplicant showing up. This usually means that you have either configured your device to talk to 2 SSIDs, or, you have some duplication of configurations somewhere in your networking setup.

Also, I noticed some settings in your network section of the wpa_supplicant.conf file that might not be needed, and could be causing issues. You might want to try removing all of the settings in that key except for your ssid and psk, making it look like this:

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

network={
    ssid="my-sside"
    psk="my-passowrd"
}

Most wpa_supplicant settings have sane defaults. Sometimes the extra settings can cause issues unless you specifically have needs for them.

Let us know if this helps!

Answer 4

If you've 'cloned' one SD image from another you may have a problem with your /etc/udev/rules.d/70-persistent-net.rules file which is specific to the hardware.

You can rename the file to .....rules.old or simply delete:

sudo rm -f /etc/udev/rules.d/70-persistent-net.rules

This would resolve the issue.