It was meant to restart the NUT driver from a udev RUN+= when the UPS
re-enumerates on USB, but was never wired up: 50-nut-ups.rules only sets MODE
and GROUP.
systemd already covers the case. nut-driver@ups.service is Restart=always
with RestartUSec=15s, so the driver is retried indefinitely and reattaches to
a new device node unaided.
It would also not have worked reliably. systemd-udevd kills RUN+= handlers
still alive when the event completes, so the backgrounded subshell could be
killed mid-sleep, and upsdrvctl would run the driver outside the unit's
supervision, competing with systemd's own restarts.
Kept with a header recording the rule-based alternative if faster recovery is
ever wanted.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
