Arch Linux

Description:
you could edit those file and implement restarting the service on crash. we are talking about Network UPS Tools. the service is working great with zero problems, but sometimes the service crashes.
there is a possibility that in those times you'll need the service to be functional in order to power down your system. if the service is crashed, while on power outage [you've got no protection and no shutdown].
https://ma.ttias.be/auto-restart-crashed-service-systemd/

nut-monitor.service:
[Unit]
Description=Network UPS Tools - power device monitor and shutdown controller
After=local-fs.target network.target nut-server.service
[Service]
ExecStart=/usr/bin/upsmon
PIDFile=/run/nut/upsmon.pid
Type=forking
Restart=on-failure
RestartSec=5s
[Install]
WantedBy=multi-user.target

nut-server.service:
[Unit]
Description=Network UPS Tools - power devices information server
After=local-fs.target network.target nut-driver.service
# We don't Require drivers to be successfully started! This would be
# a change of behavior compared to init SysV, and could prevent from
# accessing successfully started, at least to audit a system.
Wants=nut-driver.service
Before=nut-monitor.service
[Service]
ExecStart=/usr/bin/upsd
Type=forking
Restart=on-failure
RestartSec=5s
[Install]
WantedBy=multi-user.target

nut-driver.service:
[Unit]
Description=Network UPS Tools - power device driver controller
After=local-fs.target network.target
StopWhenUnneeded=yes
[Service]
ExecStart=/usr/bin/upsdrvctl start
ExecStop=/usr/bin/upsdrvctl stop
Type=forking
Restart=on-failure
RestartSec=5s