[Nut-upsuser] Possibility to set NUT drivers to "monitor only"?

[Alexander Hofmann]

Dear all,

I might have a somewhat strange question (which might arise from my 
[rather unusual?] use case, see below): Is it possible to put the 
"blazer_usb" driver (or NUT in general) to something like a "read only" 
or "monitor only" mode in respect to the communication with the 
hardware? The idea would be to not allow NUT to switch off the power at 
the UPS at all.

Currently, I disabled the "KILLPOWER" switch, so that "upsdrvctl 
shutdown" is not called when the monitoring system is shut down (that's 
what I read in all the guides I could find online, and the only thing 
related in the manpages AFAIK). But I'm not sure what else to disable or 
change. So I though, if there's the ability to disable "control" to the 
UPS entirely at driver level, this would be the most "permanent" 
solution to make sure no "accident" occurs?


If you have another Idea, here's the "real" problem:

I'm monitoring a UPS (FSP "Clipper", working with driver blazer_usb) 
that's controlling power to a inert-gas glovebox-system in a laboratory, 
with some additional "support" hardware. The goal is to record power 
usage and lifetime data of the UPS 1st, shutdown on power loss 2nd. The 
system actually has no means to be "safely shutdown" in an automated 
way, so most of the usual "protocols" to follow for servers or storage 
or... do not apply to the system itself. I can of course control other 
devices or shutdown stuff that's not mandatory to reduce power usage. 
Thus: I might issue shutdown commands to PCs, power strips etc. powering 
measurement equipment, or the monitoring system, but will keep the "main 
thing" running as long as the UPS hardware can handle it (at that time, 
all other "intelligent" devices are already off, including NUT itself, 
at least that's the plan). Such an event occurs maybe once a year, if at 
all...

So far, I think disabling UPS shutdown at system shutdown is the only 
thing I really need, but as the system is rather crucial to our 
workflow, I wanted to make sure. The more changes I have to make to the 
"default" configuration, the more to check at each update...

Thank you for your patience in reading my story :-)


Best regards,

Alex