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andyturfer

Member

Registered: 2021-01-08

Posts: 104

[SOLVED] LUKS password screen during boot very dim

I'm using LUKS drive encryption. When I boot my laptop, the LUKS password screen (which is in text mode) is extremely dim. In a normal room with the lights on, I can barely see that it's prompting me to enter my LUKS password.

Is there any way of increasing the brightness on the LUKS password screen?

UPDATE: Forgot to mention that I have tried the brightness keys (media keys) - they do not work on the LUKS screen.

Last edited by andyturfer (2025-06-18 00:34:31)

Xeauron

Member

From: Manchester, UK

Registered: 2023-07-10

Posts: 27

Re: [SOLVED] LUKS password screen during boot very dim

On any given laptop there is usually a function key at the bottom left of your keyboard labelled 'Fn' - you should also have two keys with brightness icons on there normally one of your function keys across the top fo your keyboard (F1 - F12) like this:

Press and hold the 'Fn' key then tap the brightness button which should allow you to increase the brightness.

andyturfer

Member

Registered: 2021-01-08

Posts: 104

Re: [SOLVED] LUKS password screen during boot very dim

On any given laptop there is usually a function key at the bottom left of your keyboard labelled 'Fn' - you should also have two keys with brightness icons on there normally one of your function keys across the top fo your keyboard (F1 - F12) like this:
https://imgs.search.brave.com/hAGXdZGgd … 0xMjgucG5n

Press and hold the 'Fn' key then tap the brightness button which should allow you to increase the brightness.

Sorry, I should have provided more information in my original post - none of the media (brightness) keys work on the LUKS screen.

andyturfer

Member

Registered: 2021-01-08

Posts: 104

Re: [SOLVED] LUKS password screen during boot very dim

I found a solution:

1. Find out the backlight file:

# ls /sys/class/backlight/
amdgpu_bl1

2. Test and see what brightness level you want:

#  echo 100 > /sys/class/backlight/amdgpu_bl1/brightness
#  echo 150 > /sys/class/backlight/amdgpu_bl1/brightness

3. Create an initcpio file:

#  vi /etc/initcpio/hooks/set-brightness

Contents:

run_hook() {
    echo 200 > /sys/class/backlight/amdgpu_bl1/brightness
}

4. Create a corresponding initcpio install script:

# vi /etc/initcpio/install/set-brightness

Contents:

#!/bin/bash

build() {
    add_runscript
}

Make it executable:

# chmod +x /etc/initcpio/install/set-brightness

5. Add it to the "HOOKS=" line before "encrypt"  in /etc/mkinitcpio.conf:

HOOKS=(base udev autodetect microcode modconf kms keyboard keymap consolefont block set-brightness encrypt filesystems fsck)

6. Rebuild InitRamFS:

# mkinitcpio -P

After rebooting, the LUKS password text mode screen was bright!