I wrote up an article regarding this.
NUT USB APC BeagleBone
<https://blog.raymond.burkholder.net/index.php?/archives/1360-NUT-USB-APC-BeagleBone.html>
For some reason, USB devices 'disconnect' and reconnect. When the device
reconnects, a new DeviceID is assigned to the USB device. This breaks
the usbhid-ups drivers supplied by NUT the packages. That is, usbhid-ups
no longer sees the APC USB device.
To resolve this, I used Debian's udev system to sense the device id
change and to restart the NUT USB driver.
# cat /etc/udev/rules.d/89-usb-ups-change.rules
SUBSYSTEM=="usb", MODE="0660", ACTION=="add",
ENV{ID_VENDOR_ID}=="051d", ENV{ID_MODEL_ID}=="0003",
RUN+="/home/debian/usb_add.sh add '$env{DEVNAME}' '$env{ID_USB_SERIAL}'"
SUBSYSTEM=="usb", MODE="0660", ACTION=="remove",
RUN+="/home/debian/usb_remove.sh remove $env{DEVNAME}"
Sense a removal, which stops nut.target
$ cat usb_remove.sh
#!/usr/bin/env bash
logger "USB state change detected: $1 $2"
echo "$(date) USB state change detected: $1 $2" >>
/home/debian/usb-log.txt
#systemctl stop nut.target
exit 0
Sense an addition, which restarts / starts
$ cat usb_add.sh
#!/usr/bin/env bash
logger "USB state change detected: $1 $2 $3"
echo "$(date) USB state change detected: $1 $2 $3" >>
/home/debian/usb-log.txt
systemctl restart nut.target
exit 0
The blog entry has more detail about parameters
Raymond
https://blog.raymond.burkholder.net
On 2026-07-22 21:02, Robert Nichols via Nut-upsuser wrote:
Is there a way to prevent the usbhid-ups driver from flooding the
system log when a monitored UPS is disconnected from its UCB port. I
see a steady stream of messages:
 usbhid-ups[3480520]: libusb1: Could not open any HID devices:
insufficient permissions on everything
that are posted every 2 seconds until I comment out that device from
ups.conf and restart the nut service.
Version is nut-2.8.2-1.el8.x86_64 in Rocky Linux 8.
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