[Nut-upsuser] usbhid-ups flooding system log

[Jim Klimov]

One thing that comes to mind is that a few releases ago the conditions to
issue this message were refactored, so it would not be printed for each
situation where no USB devices could be opened, but only where it actually
relates to lack of permissions (all tried devices had EACCESS).

Another was a discussed, possibly fixed and merged (not sure OTOH), change
of reconnection logic to not blindly retry same data points as were seen
before (which become obsolete due to kernel-side re-enumeration) but to
re-discover devices more diligently.

With 2.8.2 baseline, maybe your NUT deployment is just too old on those
counts and one or both troubles could have been already resolved in the
years since that release.

Consider following
https://github.com/networkupstools/nut/wiki/Building-NUT-for-in%E2%80%90place-upgrades-or-non%E2%80%90disruptive-tests
and checking if that is the case, please.

Other than that, it could be argued that as NUT is in the business of
monitoring UPSes to provide timely shutdowns in case of power outage, a
prolonged data outage is something important that the sysadmin should
address (even if by disabling the driver for a known maintenance). That
said, I've recently reviewed many drivers for
https://github.com/networkupstools/nut/pull/3541 and many of them already
generally throttle reconnection notifications (although each one that
does - reinvented their own wheel in this regard... something to address in
that PR or later). The message you reported comes from an internal library
shared by many USB-capable drivers and might not fall under driver-decided
log throttling rules though.

Hope this helps,
Jim Klimov



On Thu, Jul 23, 2026 at 5:15 AM Robert Nichols via Nut-upsuser <
nut-upsuser at alioth-lists.debian.net> 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.
>
> --
> Bob Nichols     "NOSPAM" is really part of my email address.
>                  Do NOT delete it.
>
>
> _______________________________________________
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