Ubuntu – How to setup Wifi using the command-line

command linewireless

How do I setup Wifi using the command line?

I need to setup as following, but its failed:

Target:

Security: WEP
Network name: wifi59/7
Key/password: xyz

Tried and failed:

sudo iwconfig wlan0 mode managed
sudo iwconfig wlan0 channel 11
sudo iwconfig wlan0 essid wifi59/7
sudo iwconfig wlan0 key xyz
Error for wireless request "Set Encode" (8B2A) :
    SET failed on device wlan0 ; Invalid argument.

Best Answer

The WEP key should be in hex, and either 10 or 26 characters long (5 or 13 ASCII bytes).

If you want to specify it in ASCII, you have to prefix it with s: - I'm not sure if iwconfig will pad out an ASCII password, but try lengths of 5 or 13.

See man iwconfig and scroll down to key/enc[ryption] for some examples.

Related Solutions

Ubuntu – How to set wifi driver settings to prefer 5 GHz channel above 2.4 GHz

Change that "Ad-hoc" option to something else, like "Infrastructure" (or a similar menu option). Infrastructure wireless is your typical "lots of devices connecting to a single router" approach, while ad-hoc wireless is intended for a "mesh" of wireless devices with no centralized router.

Being in ad-hoc mode is likely what's causing your problem (and this is further evidenced by the error message you provided).

Ubuntu – How to keep the Wifi from dropping out

Run the following commands, one line at a time in the terminal (CTRL+ALT+T):

echo "options iwlwifi 11n_disable=1" | sudo tee /etc/modprobe.d/iwlwifi.conf
sudo modprobe -rfv iwldvm
sudo modprobe -rfv iwlwifi
sudo modprobe -v iwlwifi

What does this do? The 11n_disable option disables 802.11n features. Adding it to /etc/modprobe.d/iwlwifi.conf makes the change persist after reboots (because it will be part of the module config). The modprobe -rfv commands are removing the kernel modules iwldvm and iwlwifi, and finally the last line modprobe -v is adding iwlwifi back in.

To know what those kernel modules are/do, you can run modinfo <module name> | grep description, which will tell you the following:

iwlwifi is an Intel(R) Wireless WiFi driver for Linux (generic Intel drivers)

iwldvm is Intel(R) Wireless WiFi Link AGN driver for Linux (more specific drivers)

Other suggestions

Now, check the settings in the router. WPA2-AES is preferred; not any WPA and WPA2 mixed mode and certainly not TKIP. Second, if your router is capable of N speeds, You may have better luck with a channel width of 20 MHz in the 2.4 GHz band instead of automatic 20/40 MHz. I also have better luck with a fixed channel, either 1, 6 or 11, rather than automatic channel selection. After making these changes, you may need to reboot the router.