Connect to Wi-Fi on Ubuntu via Command Line

Lately I have been using Ubuntu servers a bit more. In the past I have installed nmcli for configuring Wi-Fi connections. For servers, I am usually going to set it and forget it. So rather than install something I would only need once, I will go straight to the configs. By the way, I recommend using a wired connection for servers. Especially in production environments. With that said, here are the instructions.

First, find out the name of the interface you need to configure.

sudo ifconfig # If it is not found, try `iwconfig`

You will see something like the output below.

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 8903  bytes 7904472 (7.9 MB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 8903  bytes 7904472 (7.9 MB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

wlp3s0: IEEE 802.11  ESSID:off/any
          Mode:Managed  Access Point: Not-Associated   Tx-Power=22 dBm
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:on

The name of the interface we need to update in the configs is wlp3s0. Modify or create /etc/netplan/50-cloud-init.yaml. You should end up with something like the following config. Change wlp3s0 as needed. If the wifis section does not exist already, just copy and past it somewhere in the network section. Keep in mind this is a YAML file which requires correct indentation.

network:
  version: 2
  wifis:
    wlp3s0:
      dhcp4: true
      access-points:
        "jasonrav_wifi_essid":
          auth:
            key-management: "psk"
            password: "Bosco"

Apply the new netplan config.

sudo netplan apply

For troubleshooting, try using this.

sudo netplan --debug apply