[Nut-upsuser] Shutdown after 5 minutes?

[Peter Selinger]

Rob wrote:
> 
> What would I be looking for that I didn't see in my testing with my 
> windows box?  Should I be trying to sniff the serial connection to see 
> if the UPS is for some reason sending a weird signal that NUT is 
> mis-interpreting?  If so, how would you recommend I do that?

I would try the following: plug your computer into a wall outlet, plug
a desk lamp into the UPS. First, start the driver and upsd (but not
upsmon). Monitor the ups variables with upsc. Pull the power, wait 5
minutes or more, see what happens. Are there changes to ups.status?
Does the lamp go off? Normally, the lamp should not go off until the
battery runs out, which should happen some time after ups.status shows
"LB" (low battery). If the lamp goes off before that, there's a
problem. 

Then try the same thing again, this time with upsmon running. When the
UPS gets to "LB", then upsmon should start slowly shutting down the
computer. When the computer is in a safe state, the lamp should go off
(the computer will stay on, as it doesn't know it is not plugged into
the UPS). 

It could be that something is misconfigured in your shutdown scripts,
for example, perhaps you call "upsdrvctl shutdown" way too early. This
would yank the power from your UPS. In the above setup, you would see
the lamp go off as the computer is preparing to shut down. 

-- Peter


> Peter Selinger wrote:
> > That is very odd indeed. Why should the system shut off abruptly? If
> > the log shows nothing, then it seems that the UPS just turned off the
> > power. 
> > 
> > I recommend testing this while attaching, say, a lamp to the UPS,
> > instead of a computer. (You can still use your computer to monitor the
> > UPS, just don't plug it into it!)
> > 
> > -- Peter
> > 
> > Rob wrote:
> >>> Upsmon is responsible for monitoring and reacting to power events.
> >>> See also the man pages for upsmon(8), upsmon.conf(5), upssched(8), and
> >>> upssched.conf(5). 
> >>>
> >>> There could be many reasons your Windows machine lasts longer than
> >>> your Linux machine on their respective UPSs. Perhaps the battery on
> >>> the second one is older, or has lost some of its charge, or is lower
> >>> quality... Batteries tend to wear out quite easily, especially if they
> >>> are discharged and recharged a few times.
> >>>
> >>> Did you try switching the two machines?
> >> On my system, I only have 1 UPS and I have monitored it in windows and 
> >> in Linux.  In windows, the same set of systems will properly wait until 
> >> the designated time to shutdown (>5 minutes).  When I boot into Linux, 
> >> my Linux system performs an abrupt poweroff after about 5 minutes.  I 
> >> notice that UPS has been shutoff, but that the system has not been 
> >> shutdown cleanly as the logs do not show a system shutdown and disks 
> >> need to be recovered on bootup.
> >>
> >> In windows, I monitored the power output and saw that the battery 
> >> drained very quickly down to 60%, and then stabilized.  I contacted 
> >> CyberPower about this and they stated that this is a normal discharge 
> >> pattern for SLA batteries.  Does NUT possibly detect the power drain 
> >> rate and perform an action based upon that?  Even if the UPS was sending 
> >> a low power indicator, I can't see why NUT wouldn't do a clean shutdown 
> >> of the system?
> >>
> >> Rob
> >>
> > 
> > 
> > 
>