[Nut-upsuser] NUT support for APC BackUPS Pro 900VA

Gene Heskett gheskett at wdtv.com
Fri Jan 22 05:46:14 UTC 2016

On Thursday 21 January 2016 17:36:15 Juergen Edner wrote:

> Hi all,
> I'm trying to configure Nut to connect to an APC BackUPS Pro 900VA.
> This ups uses a serial port on which _simple_ or _smart_ signaling
> should be spoken. I've connected the UPS to a serial port using the
> original 940_0128A cable from APC.
> Unfortunately I've not yet managed to read any data from the ups.
> If I try to load the apcsmart driver it tells me that it cannot
> communicate with the ups.
> Does anyone be able to configure Nut so that the mentioned BackUPS
> is recognized properly. If someone could give me a hint how I need
> to configure nut, I would appreciate it.
> Just to mention, Nut is already working with older SmartUPS devices
> without any problems. So it isn't a general but a device specific
> problem.
> Thank you in advance!
> Regards
> Juergen

This might not be helpfull, but is udev now setting the permissions on 
that serial port restrictive enough that nut cannot use it?

After heyu was refused at midnight 1/1/16 when I have a cron job upload 
the next years schedule for some lights on the front deck, I 
found /dev/ttyUSB0 was set to root:root for ownership, and 0700 
permissions.  Meaning only root could use it.

I just had a similar situation using heyu on /dev/ttyUSB0. I could not 
find the udev rule that had changed it, so I took the next best route, 
got root and put a chmod and a chown of that port in my /etc/rc.local 
file, which runs last at bootup.  And heyu is once again a happy camper.

This might not be your problem, but its something to check.

Cheers, Gene Heskett
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>

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