Linux – Can the Linux box turn off the UPS after it shuts down

linuxunixups

I have an APC UPS with all my computer peripherals plugged into it. When I'm done using the computer, I'd like to be able to type "shutdown" or "init 0" and walk away from the machine, trusting that it will shut down cleanly and then signal the UPS to shut off power to all peripherals.

I understand that there is a "kill the power" signal that APC UPSes can be sent, and I have that working in the event of a power failure: apcupsd will shut down the computer and, at the last moment, tell the UPS to turn off. But this only works when running on battery.

When it gets that killpower signal while running on AC power, the UPS turns off for a few seconds, and then it turns right back on automatically. Is this expected behavior? Can it be disabled, so that the UPS stays off, even when there is AC power?

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try nut

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Windows – How to set the Windows 7 desktop with a UPS to automatically turn on after a power outage is over

Apcupsd does do what you want. Our power here is really bad. In the event of a power failure, my system stays on battery for 2 minutes (my choice) in case it is a short duration. After being on battery for 2 minutes, Apcupsd tells the UPS to cut the power to the PC. The UPS has a built in delay of 2 minutes. Apcupsd then issues the Windows hibernate command, so Windows hibernates. Two minutes after the UPS was sent the command, it cuts power to the PC. When power is restored (or if it was already) then the UPS again provides power. You are correct - since the BIOS sees this as the power was cut then restored, the BIOS will do what you set it to do.

A clean shutdown using a UPS - if the UPS does not cut the power to the PC, regardless of whether the power is restored or not, your PC will remain shutdown because the BIOS didn't see a power cut/restore. The BIOS has no other choice. If, when your system shut down, the BIOS detected that power was still present, what would you want it to do - power up the machine? Then there'd be no way to shut your system down.

BIOS requires that PC loses and then gets back the power.

Linux – Turn off keyboard backlight when shutting down Linux

In my Kubuntu the right place is /sys/class/leds/.

# ls /sys/class/leds/
dell::kbd_backlight  input4::capslock  input4::numlock  input4::scrolllock  phy0-led  xpad0

Most certainly, if your Metoo Zero backlight is there, it will be something other than dell::kbd_backlight, so the below commands are just examples.

# ls "/sys/class/leds/dell::kbd_backlight"
brightness  device  max_brightness  power  start_triggers  stop_timeout  subsystem  trigger  uevent
# cat "/sys/class/leds/dell::kbd_backlight/max_brightness"
2

This number suggests my backlight has three states. I can run (as root):

# echo 0 > "/sys/class/leds/dell::kbd_backlight/brightness"
# echo 1 > "/sys/class/leds/dell::kbd_backlight/brightness"
# echo 2 > "/sys/class/leds/dell::kbd_backlight/brightness"

It turned out the states are: 0=off, 1=dimmed, 2=bright.

If it works for you, make your Linux execute the appropriate command before it shuts down (I believe the way to do it is distribution-dependent).

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Windows – How to set the Windows 7 desktop with a UPS to automatically turn on after a power outage is over

Linux – Turn off keyboard backlight when shutting down Linux

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