# phpman > man > systemd-backlight@.service(8)

SYSTEMD-BACKLIGHT@[.SERVICE(8)](https://www.chedong.com/phpMan.php/man/.SERVICE/8/markdown)        systemd-backlight@.service        SYSTEMD-BACKLIGHT@[.SERVICE(8)](https://www.chedong.com/phpMan.php/man/.SERVICE/8/markdown)



## NAME
       systemd-backlight@.service, systemd-backlight - Load and save the display backlight
       brightness at boot and shutdown

## SYNOPSIS
       systemd-backlight@.service

       /lib/systemd/systemd-backlight save [backlight|leds]:DEVICE

       /lib/systemd/systemd-backlight load [backlight|leds]:DEVICE

## DESCRIPTION
       systemd-backlight@.service is a service that restores the display backlight brightness at
       early boot and saves it at shutdown. On disk, the backlight brightness is stored in
       /var/lib/systemd/backlight/. During loading, if the udev property **ID**___**BACKLIGHT**___**CLAMP** is not
       set to false, the brightness is clamped to a value of at least 1 or 5% of maximum brightness,
       whichever is greater. This restriction will be removed when the kernel allows user space to
       reliably set a brightness value which does not turn off the display.

## KERNEL COMMAND LINE
       systemd-backlight understands the following kernel command line parameter:

       _systemd.restore_state=_
           Takes a boolean argument. Defaults to "1". If "0", does not restore the backlight
           settings on boot. However, settings will still be stored on shutdown.

## SEE ALSO
       [**systemd**(1)](https://www.chedong.com/phpMan.php/man/systemd/1/markdown)



systemd 249                                                            SYSTEMD-BACKLIGHT@[.SERVICE(8)](https://www.chedong.com/phpMan.php/man/.SERVICE/8/markdown)