[Nut-upsuser] Unable to open /dev/cuad0: Device busy

Arjen de Korte nut+users at de-korte.org
Thu Oct 12 09:12:15 UTC 2006

> freebsd 540$ /usr/local/etc/rc.d/nut restart
> nut not running? (check /var/db/nut/upsd.pid).
> Network UPS Tools - UPS driver controller 2.0.4
> Network UPS Tools - Generic UPS driver 1.32 (2.0.4)
> UPS type: APC Back-UPS (940-0023A cable)
> Unable to open /dev/cuad0: Device busy

Stopping a driver is an asynchronous process. Therefor, if you restart
NUT, you may attempt to start the driver again before the previous one has
stopped (and may still be locking the port). In that case, adding a delay
of about three seconds between stopping and starting is usually sufficient
to fix this. You can do this by adding 'sleep 3' in the startup script
between the stopping and starting of the driver, or alternatively stop and
start the driver from the commandline.

Best regards,
Eindhoven - The Netherlands
Key fingerprint - 66 4E 03 2C 9D B5 CB 9B  7A FE 7E C1 EE 88 BC 57

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