Fix ubuntu Each restart screen brightness is reset to the highest brightness issue

Many friends will encounter this problem, Ubuntu system, each time through the system settings to modify the screen brightness, restart the system will be the screen brightness is adjusted to the maximum value, is very distressed.

Internet search found that the file to modify the screen brightness is:/sys/class/backlight/intel_backlight/brightness

We can set the screen brightness by manually modifying this file, and add it to the boot boot.

Specific steps:

1. View current Brightness value

$ cat/sys/class/backlight/intel_backlight/brightness
4437 #此亮度值是我笔记本的最高亮度

2, through the "System settings" ==> "Brightness and lock Screen", set the screen brightness to their own state of adaptation, and here to view the system brightness file data.

$ cat/sys/class/backlight/intel_backlight/brightness

#个人习惯亮度

3, manually modify the system brightness to the brightest, and manually modify the file, test whether it can successfully adjust the screen brightness

$ sudo echo >/sys/class/backlight/intel_backlight/brightness

Some computers may appear not to have permission to prompt (according to normal, sudo should not prompt this, but I do not prompt enough permission)

4. Modify Permissions

$ sudo chmod o+w/sys/class/backlight/intel_backlight/brightness

5, modify the permissions can be directly modified, do not need sudo

echo >/sys/class/backlight/intel_backlight/brightness

6, if the screen brightness adjustment is successful, you can add this sentence to/etc/rc.local each boot

$ sudo vi/etc/rc.local

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echo >/sys/class/backlight/intel_backlight/brightness <--end plus one line

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This is done, reboot the system and try it!

Fix ubuntu Each restart screen brightness is reset to the highest brightness issue