In this article I will show Raspberry Pi 4 Ubuntu WiFi Setup from command line.
Identify The WiFi Card Name In Raspberry Pi 4 Ubuntu
Raspberry Pi 4 has hardware WiFi card already onboard, but you can add other USB WiFi device.
First lets identify interfaces in system.
Information regarding network interfaces we can find in /sys/class/net file:
$ sudo ls /sys/class/net eth0 lo wlan0
In our case we have 1 WiFi card and interface name is wlan0.
Edit the Netplan Configuration File
Open Netplan configuration file with any text editor (nano, vim):
$ sudo nano /etc/netplan/50-cloud-init.yaml
And add wifis section in config as shown in example:
# This file is generated from information provided by the datasource.  Changes
# to it will not persist across an instance reboot.  To disable cloud-init's
# network configuration capabilities, write a file
# /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg with the following:
# network: {config: disabled}
network:
    ethernets:
        eth0:
            dhcp4: true
            optional: true
    wifis:
        wlan0:
            dhcp4: true
            access-points:
                "WIFI SSID":
                    password: "WiFi Password"
    version: 2
Then save and close file.
Apply New Netplan
To apply netplan in Ubuntu execute:
$ sudo netplan --debug try $ sudo netplan --debug generate $ sudo netplan --debug apply
And reboot with command:
$ sudo reboot
After reboot your Raspberry Pi with installed Ubuntu will automatically connect to your WiFi access point.
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