WiFi Networking without NetworkManager

The NetworkManager.service provides a simple way to configure WiFi networking on Linux systems, but it can cause issues when running in a custom setup (in my case with multiple network adapters).

The following steps will disable the NetworkManager and allow configuring the WiFi through wpa_supplicant. They should work for most Linux distributions that use systemd (e.g. Debian, Raspbian, Kali Linux, etc.).

1 Disable the NetworkManager service

systemctl disable NetworkManager
systemctl stop NetworkManager

2 WiFi configuration

Create /etc/wpa_supplicant/wpa_supplicant.conf based on the following template:

country=..		# ISO_3166 country code
update_config=1
ctrl_interface=/var/run/wpa_supplicant

network={
        scan_ssid=1
        ssid="Network SSID"     # WiFi SSID to connect to
        psk="password"      # Password
}

3 Apply the WiFi configuration on boot

Add the following lines to /etc/rc.local or create the file if it does not exist.

#!/bin/bash

(
        # Enable the network interface. Repeat this line for any other wifi interfaces 
        # that you want to use.
        ip link set wlan0 up
        
        # Connect to the configured access point using the wlan0 interface
        wpa_supplicant -B -i wlan0 -c /etc/wpa_supplicant/wpa_supplicant.conf
        dhclient -v wlan0
        
) &> /var/log/local_inet.log &

If you’ve just created the rc.local file, you will also need to mark it as executable:

sudo chmod a+x /etc/rc.local

4 Reboot

sudo reboot