Suggestion from https://forum.vyos.io/t/vyos-and-a-linux-supported-ups/13379
Request to add capabilities for VyOS to directly communicate with attached UPS (I assume through USB) for monitoring but also to make a clean poweroff when the UPS reports a battery level below a specific percentage.
Sample config files here: https://github.com/networkupstools/nut/tree/master/conf
Here's my config from a system running truenas-scale (debian based). I'm using an APC Smart Ups connected by USB cable.
nut.conf
MODE=netserver
ups.conf
[ups]
driver = usbhid-ups
port = /dev/uhid
desc = "UPS Service"upsd.conf
LISTEN 127.0.0.1 3493 LISTEN ::1 3493
upsmon.conf
NOTIFYCMD /usr/sbin/upssched NOTIFYFLAG ONBATT SYSLOG+EXEC NOTIFYFLAG LOWBATT SYSLOG+EXEC NOTIFYFLAG ONLINE SYSLOG+EXEC NOTIFYFLAG COMMBAD SYSLOG+EXEC NOTIFYFLAG COMMOK SYSLOG+EXEC NOTIFYFLAG REPLBATT SYSLOG+EXEC NOTIFYFLAG NOCOMM SYSLOG+EXEC NOTIFYFLAG FSD SYSLOG+EXEC NOTIFYFLAG SHUTDOWN SYSLOG+EXEC SHUTDOWNCMD "/sbin/shutdown -h now" HOSTSYNC 15
upssched.conf
CMDSCRIPT "/usr/bin/sudo /usr/local/bin/custom-upssched-cmd" PIPEFN /var/run/nut/upssched.pipe LOCKFN /var/run/nut/upssched.lock AT NOCOMM * EXECUTE NOTIFY-NOCOMM AT COMMBAD * START-TIMER NOTIFY-COMMBAD 10 AT COMMOK * CANCEL-TIMER NOTIFY-COMMBAD COMMOK AT FSD * EXECUTE NOTIFY-FSD AT LOWBATT * EXECUTE NOTIFY-LOWBATT AT ONBATT * EXECUTE NOTIFY-ONBATT AT ONLINE * EXECUTE NOTIFY-ONLINE AT REPLBATT * EXECUTE NOTIFY-REPLBATT AT SHUTDOWN * EXECUTE NOTIFY-SHUTDOWN AT ONBATT * START-TIMER SHUTDOWN 30 AT ONLINE * CANCEL-TIMER SHUTDOWN