How to automate keyboard backlight ON at boot

Question

Right now I am running a cooler Master keyboard on Kubuntu 16.04. At present I have to run

xset led 3

in Konsole in order to turn the keyboard on, which is a PITA.

How can I instruct the system to light the keyboard at boot, particularly before and after the login screen?

I would put the command in /etc/rc.local but you can also use a cron job with @reboot. See: askubuntu.com/questions/228304/… — WinEunuuchs2Unix, Jan 7, 2018 at 19:31
Can I enter the command as is, or should I enter a pathway for an *.sh file? — Timbot2000, Jan 7, 2018 at 20:12
You can enter the command as is. A *.sh (script) file is typically only used for multi-line commands. When using cron you must find out the directory name to prefix the command. ie use which xset returns: /usr/bin/xset which is the exact command format you need to use. The simpler method is just to put the command in /etc/rc.local rather than using cron. — WinEunuuchs2Unix, Jan 7, 2018 at 20:23
Sorry WinEunuuchs2Unix, entering it in the rc.local file failed to enact the command at startup. What do we try next? — Timbot2000, Jan 8, 2018 at 2:49
Sorry the rc.local didn't work out. I've posted an answer which I hope does work. — WinEunuuchs2Unix, Jan 8, 2018 at 3:42

Community · Accepted Answer · 2020-06-12 14:37:07Z

Using "Startup Applications" instead of `/etc/rc.local`

Select the first option on your Launcher called Dash. Then type "startup" and a screen similar to this will appear:
Select the option "Startup Applications" and a screen similar to this will appear:
Select Add and this screen will appear:
Make sure you enter the command as: /usr/bin/xset led 3
I entered the comment as: Ubuntu 16.04 regular crash, Compiz segfault, error 4 in i965_dri.so, Fresh install but you don't need to.

I can't test this on my system because the Laptop's built-in keyboard and wireless keyboard both light up automatically.

You can't put xrandr commands in /etc/rc.local because it runs before a user logs in. xrandr commands can only be used after the user logs on.

I can confirm, this actually works on Linux Mint 19.1
– falconR
Dec 27, 2018 at 23:37 — falconR, Dec 27, 2018 at 23:37