Wi-Fi

This chapter describes common information and instructions of Wi-Fi on IoT Yocto, such as command to configure DHCP or static IP and so on.

But Wi-Fi on different platforms may have some platform-specific instructions or test results. For example, you will get different throughputs on different platforms.

Connect to a Wi-Fi AP

There are two methods to connect evaluation board to a Wi-Fi network: NetworkManager and wpa_supplicant.

NetworkManager is a high level service and should be used when possible, since it automatically configures wpa_supplicant and other system states.

Connect to a network via NetworkManager

First, make sure service NetworkManager (NetworkManager) is running:

systemctl status NetworkManager.service

You should see an output line like this:

Active: active (running)

If not, launch NetworkManager:

systemctl start NetworkManager.service

Now, please remove the old config file from /etc/wpasupplicant.conf, if wpa_supplicant has been used before. This configuration file interferes NetworkManager.

rm -rf /etc/wpasupplicant.conf

Finally, run nmcli command to configure and connect the board to WIFI with NetworkManager:

Note

Interface name <IFNAME> may be different by modules. It should be wlan0 or wlp1s0 usually. The name depends on the driver default when the module is probed.

nmcli device wifi connect <SSID> ifname <IFNAME> password <PASSWD>

nmcli would report the connection result with following log:

Device 'wlan0' successfully activated with 'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx'.

If everything works fine, you should be able to connect to the internet:

# Check if the board is actually connected to the internet.
ping www.google.com

Connect to a network via wpa_supplicant

Use this method only if you want to avoid using NetworkManager.

First, stop NetworkManager:

systemctl stop NetworkManager.service

To double check that NetworkManager has been stopped:

systemctl status NetworkManager.service

There should be a status log saying: Active: inactive (dead).

Now, configure /etc/wpa_supplicant.conf with this command:

wpa_passphrase <SSID> <PASSWD> > /etc/wpa_supplicant.conf

And then verify the configuration file by running the following command:

cat /etc/wpa_supplicant.conf

The generated content of wpa_supplicant.conf should be similar to this:

network={
    ssid="<SSID>"
    #psk="<PASSWD>"
    psk=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
}

And we also have to configure the DNS server address:

echo "nameserver x.x.x.x " > /etc/resolv.conf

After setting resolv.conf, restart systemd-resolved service:

systemctl restart systemd-resolved.service

Finally, launch wpa_supplicant with new configuration:

wpa_supplicant -B -i <IFNAME> -c /etc/wpa_supplicant.conf &

And you should now be able to connect to the internet:

ping www.google.com

Reference Boards

Wi-Fi on different platforms may have some platform-specific instructions or test results. For example, you will get different benchmark results on different platforms. Please find more details about difference of Wi-Fi on each platform: