• Install sbopkg https://sbopkg.org/
• Create user nut and group nut
• Use sbopkg to download/build/install system/nut
• Check device info for your connected UPS:
  root@pn41:/etc/nut# lsusb
.
.
Bus 001 Device 006: ID 0463:ffff MGE UPS Systems UPS
.

• Edit /etc/nut/ups.conf and add your device:
  [myups]
driver = usbhid-ups
port = auto
vendorid = 0463
pollfreq = 30

• Add an user to /etc/nut/upsd.users:
  [user]
password = password
upsmon master
actions = SET
instcmds = ALL

# To be used by monitoring client
[client]
password = password2
upsmon slave

• Edit and configure /etc/nut/upsmon.conf.sample and save as upsmon.conf:
  MONITOR myups@localhost 1 user password master
NOTIFYCMD /etc/nut/sendupsmsg
NOTIFYFLAG ONLINE SYSLOG+WALL+EXEC
NOTIFYFLAG ONBATT SYSLOG+WALL+EXEC
NOTIFYFLAG LOWBATT SYSLOG+WALL+EXEC
NOTIFYFLAG REPLBATT SYSLOG+WALL+EXEC

• Edit /etc/nut/nut.conf (to allow other clients to connect):
  MODE=netserver

• Edit /etc/upsd.conf and specify which NIC that should be used for outside connections:
  LISTEN 192.168.1.9 3493
LISTEN 127.0.0.1 3493

• Edit script (/etc/nut/sendupsmsg) that will be called if NOTIFYFLAG with flag EXEC kicks in:
  #!/bin/bash
echo $(date): "$*" >> /var/log/ups.log
# Replace with your own script for alert.
sendupsemail "$*"

• Set correct file permissions:
  chown root:nut /etc/nut/* /var/log/ups.log
chmod 650 /etc/nut/* /var/log/ups.log
chmod +x /etc/rc.d/rc.ups
chmod 750 /etc/nut/sendupsmsg

• Add rc.ups to /etc/rc.d/rc.local:
  if [ -x /etc/rc.d/rc.ups ]; then
/etc/rc.d/rc.ups start
fi

• Add shutdown cmd to /etc/rc.d/rc.local_shutdown:
  if [ -f /etc/killpower ]; then
# Stop ups service:
echo "Stopping ups stuff: upsdrvctl shutdown"
upsdrvctl shutdown
fi

• Start the services:
  /etc/rc.d/rc.usp start

• Check if it works:
  upsc myups

• Pull the plug and check syslog and that the notify script is called

• A good Windows client for NUT:
  https://github.com/gawindx/WinNUT-Client/releases

• Network UPS Tools
• NUT