Advanced apcupsd configuration WARNING for hybrid sleep (suspend to both) Hybrid sleep works properly only on human operated desktop systems. Do not use hybrid sleep on machines that need to automatically turn on after power outage! If the power returns while the computer sleeps but before battery goes out of power, the UPS has no way to wake the device. Suspend to disk If you want to configure nut to do suspend to disk instead of shutdown you should: - Verify, that suspend to disk works correctly on your machine, e. g. by systemctl hibernate (You can lose your unsaved data, if your computer does not hibernate correctly.) - Verify, that your UPS provides reasonable grace period to complete hibernation in all situations. - Use YaST Sysconfig editor and set Hardware->UPS->APCUPSD_POWERFAIL_BEHAVIOR to "hibernate". Environment with possible service timeouts In some environments, there is no guarantee, that the machine will correctly shut down, either because other machines providing critical services are already down or because some services (e. g. squid) are stopping too long and battery power is not sufficient. In this case, you can prefer incorrect but fast shutdown. To fix this problem, you need to do: - Copy apcupsd-early-powerdown script to your /etc/init.d/ directory. - Edit following lines: Replace "FIXME scripts which should not stop before powerdown" by an appropriate init script list. Replace "FIXME scripts which should stop before powerdown" by an appropriate init script list. - Start YaST Runlevel Editor and enable this meta-service in runlevels, where you want to apply early shutdown.