Connect raspberry pi 4 with ubuntu server to wifi

Question

I have a Raspberry Pi 4.

As I do not have a screen and keyboard available, I connect it through an Ethernet cable.

I want the Raspberry Pi to be connected to the Wi-Fi and not via Ethernet.

I tried to update /etc/network/interfaces to:

auto lo
iface lo inet loopback

auto wlan0
iface wlan0 inet static
address 192.168.1.150
netmask 255.255.255.0
gateway 192.168.1.1
wpa-essid MYESSID12345
wpa-psk MYPASSWORD$1234567

Then I am running:

sudo dhclient wlan0

But it does not seem to work.

ifconfig returns:

eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.1.41  netmask 255.255.255.0  broadcast 192.168.1.255
        inet6 fe80::dea6:32ff:fe62:c4fc  prefixlen 64  scopeid 0x20<link>
        ether dc:a6:32:62:c4:fc  txqueuelen 1000  (Ethernet)
        RX packets 118  bytes 13529 (13.5 KB)
        RX errors 0  dropped 52  overruns 0  frame 0
        TX packets 63  bytes 9012 (9.0 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 168  bytes 12300 (12.3 KB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 168  bytes 12300 (12.3 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

wlan0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        ether dc:a6:32:62:c4:fd  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

I also tried to do it through:

iwconfig wlan0 essid name key password

Or:

iwconfig wlan0 essid name key s:password

But I have an invalid argument error because my password is 8 characters.

Error for wireless request "Set Encode" (8B2A) :
    SET failed on device wlan0 ; Invalid argument.

I also tried iwconfig wlan0 essid name using wps but it does not work.

I also tried with wpasupplicant.

Creating /etc/wpa_supplicant.conf with

network={
    ssid="ssid_name"
    psk="password"
}

and then running sudo wpa_supplicant -B -i wlan0 -c /etc/wpa_supplicant.conf -D wext

But I have errors too.

Successfully initialized wpa_supplicant
ioctl[SIOCSIWENCODEEXT]: Invalid argument
ioctl[SIOCSIWENCODEEXT]: Invalid argument

Answer 1

It works updating /etc/netplan/50-cloud-init.yaml

Adding those lines to network

wifis:
    wlan0:
        optional: true
        access-points:
            "SSID-NAME":
                password: "WIFI-PASSORD"
        dhcp4: true

Then

$ sudo netplan --debug try
$ sudo netplan --debug generate
$ sudo netplan --debug apply

and finally reboot

$ sudo reboot

Answer 2

I got headless Wi-Fi via Unbuntu 20.04 on RPi4B working without disabling cloud-init. In a 'nutshell' I used this for my network-config:

# This file contains a netplan-compatible configuration which cloud-init
# will apply on first-boot. Please refer to the cloud-init documentation and
# the netplan reference for full details:
#
# https://cloudinit.readthedocs.io/
# https://netplan.io/reference
#

#Replace the entire user-data on the imaged SD Card with this file.

version: 2
renderer: networkd
wifis:
  wlan0:
    dhcp4: true
    dhcp6: true
    optional: true
    access-points:
      "SSID":
         password: "PassPhrase"

Then, I appended the following to the end of user-data:

power_state:
  mode: reboot

My config files, step-by-step, and notes are here: https://github.com/DavidUnboxed/Ubuntu-20.04-WiFi-RaspberyPi4B.

Answer 3

Try to update /etc/network/interfaces to:

auto wlan0
iface wlan0 inet dhcp
wpa-conf /etc/wpa_supplicant.conf

create /etc/wpa_supplicant.conf with

network={
    ssid="ssid_name"
    psk="password"
}

and run sudo wpa_supplicant -B -iwlan0 -Dwext -c/etc/wpa_supplicant.conf && sudo dhclient wlan0 .

Or try to update /etc/network/interfaces to:

auto wlan0
iface wlan0 inet dhcp
    wpa-ssid YOUR-SSID-HERE
    wpa-psk YOUR-PASSWORD-HERE

and reboot.