[Nut-upsuser] Wishlist: Absorb apcupsd features and device support that may be still missing in NUT [genericups]

[Bill Gee]

Thanks, Charles!  I had no idea I could look at genericups for this.  I 
just assumed there was little or no support for APC devices in NUT. 
Wrong was I :-)

I am happy to report that I successfully converted to NUT on the system 
with the Back-UPS 650.  It correctly reports OL and OB status.  There is 
not much else it can report, but that is OK.

root at zoneminder2:/etc/ups# upsc zoneminderups
device.mfr: APC
device.model: Back-UPS
device.type: ups
driver.debug: 0
driver.flag.allow_killpower: 0
driver.name: genericups
driver.parameter.pollinterval: 2
driver.parameter.port: /dev/ttyS0
driver.parameter.synchronous: auto
driver.parameter.upstype: 2
driver.state: quiet
driver.version: 2.8.4
driver.version.internal: 1.41
ups.mfr: APC
ups.model: Back-UPS
ups.status: OL


So ...  Getting back to the original question that started this thread: 
What features would I like to see come from apcupsd to NUT?  And now the 
answer is "None!"  NUT already has all the features I need to run my APC 
devices.

===============
Bill Gee

On 2/12/26 20:32, Charles Lepple wrote:
> On Feb 12, 2026, at 1:33 PM, Bill Gee wrote:
>>
>> Hi Charles -
>>
>> The APC units I have are dumb-serial.  Back-UPS 500, Back-UPS-600 and Back-UPS-650.  They use serial cable 940-0020B.  They are listed in apcupsd as "Dumb UPS".  The sticker on the back says "Model BK650MC".
>>
>> Reading through the docs you linked, I cannot tell for sure if these are supported.
> 
> Heh, I was making it too complicated. "Dumb UPS" translates to "contact-closure" or "generic UPS" in NUT parlance. (I was concerned it was one of the early Smart serial protocol devices.)
> 
> https://networkupstools.org/stable-hcl.html?model=Back-UPS lists Cable 940-0020B, and includes the necessary configuration option for the genericups driver (upstype=2).
> 
> Here's the full genericups documentation: https://networkupstools.org/docs/man/genericups.html
> 
>> Here is a sample output from apcupsd:
>> =======================
>> Date Range: yesterday
>> APC      : 001,018,0458
>> DATE     : 2026-02-07 07:46:29 -0600
>> HOSTNAME : zoneminder2
>> VERSION  : 3.14.14 (31 May 2016) redhat
>> UPSNAME  : zoneminder2
>> CABLE    : APC Cable 940-0020B
>> DRIVER   : DUMB UPS Driver
> 
> ...
> 
> As you're probably aware, the contact-closure interface is just a bunch of modem control signals repurposed for AC/battery and battery good/low. For instance, MBATTCHG and MINTIMEL seem like they can only be compared against battery charge and time-left values that a smart UPS would provide, so I would guess that they are not currently working in apcupsd?
> 
> Given some of the uncertainty with the proprietary cables, you may want to schedule some downtime to test with a computer running a live CD, or some other system that can survive a bad shutdown without trashing important data. Monitoring should be straightforward, but the shutdown signal to the UPS (and getting NUT and the OS to play nicely around when that signal is sent) is what would give me pause.
> 
> Hope that helps,
> - Charles