How to light up back-lit keyboard?

I recently got a backlit keyboard, and I LOVE to write late at night.

But I cannot for the life of me figure out how to light it up...It lights up when first plugged in, but nothing happens after that....

It is an 'XtremeIT' keyboard. There is a video of someone on Ubuntu who managed to activate it...

Did you try the script the YouTube poster suggested in his own comments?

Basically use xset to toggle the state of the led backlight.

#!/bin/bash
if [ -f /tmp/keyboard_light ]; then
  xset -led 3 && rm /tmp/keyboard_light
else
  xset led 3 && touch /tmp/keyboard_light
fi

open terminal then type:

xset led on 

to turn on backlight, and type:

xset led off

to turn it off.

for those who land here because they also want the keyboard to light up BEFORE the login screen:

Finally Found an answer, at least for Ubuntu 14.04

as for how to get the keyboard to light up before the login screen:

edit :

/usr/share/lightdm/lightdm.conf.d/50-unity-greeter.conf

sudo gedit /usr/share/lightdm/lightdm.conf.d/50-unity-greeter.conf

add the line:

greeter-setup-script= xset led 3