[Nut-upsuser] How to send shutdown signal to UPS hardware?

Kjell Claesson kjell.claesson at epost.tidanet.se
Sat Sep 10 10:21:45 UTC 2016

fredag 9 september 2016 kl. 18:57:36 CEST skrev  Jeff Bowman:
> I learned earlier from Roger Price's excellent explanation that a proper
> configuration includes sending a 'delayed shutdown' signal to the UPS
> hardware prior to shutting down the server.

Hi Jeff.

> How is this accomplished? Does the USB driver handle this for us or must we
> do something additional?
It depends on the driver. Look in the manual for your driver and check if it
have any extra arguments. 
For example the driver I was involved in "bcmxcp" has a shutdown_delay that 
set the time between receiving the command and actually shutting off.

USBHID-UPS have a offdelay.

Set the timer before the UPS is turned off after the kill power command is 
sent (via the -k switch).

The default value is 20 (in seconds). Usually this must be lower than ondelay, 
but the driver will not warn you upon startup if it isn’t.
You set this in the "ups.conf" file.

Kjell Claesson

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