[Nut-upsuser] trouble building nut for HID-USB

[Charles Lepple]

> On Oct 12, 2016, at 2:00 PM, Dorsey, Scott B. (LARC-D316)[LITES II] <scott.b.dorsey at nasa.gov> wrote:
> 
> It does in fact show exactly what you describe.  Udev is working properly with the device file being assigned to group 
> dialout, which the nut user is in.  You were correct about my having had to install the libusb-devel kit to make 2.7.4
> build, but it does build properly and everything seems to be working well, except that the driver only sometimes loads.
> 
> About 25% of the time I get this:
>> NUT Starting UPS model drivers: Network UPS Tools - UPS driver controller 2.7.4
>> Network UPS Tools - Generic HID driver 0.41 (2.7.4)
>> USB communication driver 0.33
>> Using subdriver: TrippLite HID 0.82
> 
> and the rest of the time I get this:
>> NUT Starting UPS model drivers: Network UPS Tools - UPS driver controller 2.7.4
>> Network UPS Tools - Generic HID driver 0.41 (2.7.4)
>> USB communication driver 0.33
>> No matching HID UPS found
>> Driver failed to start (exit status=1)

In the latter case, does "lsusb" show the UPS, or is it gone from that list as well?
> 
> Which, sadly, is the same problem I was having with 2.6.5, although I think it is starting more often
> with 2.7.4.  It is very disturbing, though, to see something that only sometimes works and I am not sure
> how to diagnose it from this point.

Of all of the bugs we've had in NUT over the years, the ones at this level are the most frustrating, because we can't add log statements to the code inside the UPS to see why it is dropping off the bus. It definitely seems correlated with NUT driver activity, but the same core driver works fine with other models and vendors.

You might also benefit from adjusting these variables: http://lists.alioth.debian.org/pipermail/nut-upsuser/2016-October/010352.html

though I would consider it a stop-gap measure. At some point, unless you have many of the same model. the cost of the time to fiddle with it may exceed the value of the UPS.

> Also.... I had to write a new startup script to make 2.7.4 work with Centos 6.8.  It should work with all
> Centos 6.  Do you want a copy of it?  I am not sure I can donate it but I will see.

I'm sure that other CentOS users would appreciate it, or at least some tips on how to reproduce the script. However, a while back, we (mostly) decided to stop shipping distro-specific files in the NUT source tree itself, and instead tried to work more closely with the maintainers of those distributions. The best way might be to file a feature request with CentOS for updating to NUT 2.7.4, and include whatever portion of the script that you can in that request. Wouldn't hurt to post a link back to this list to help others who want to upgrade.