[Nut-upsuser] Shutdown variables

[Simon Wilson]

----- Message from Simon Wilson via Nut-upsuser  
<nut-upsuser at alioth-lists.debian.net> ---------
     Date: Sun, 27 Nov 2022 23:31:13 +1000
     From: Simon Wilson via Nut-upsuser <nut-upsuser at alioth-lists.debian.net>
Reply-To: simon at simonandkate.net
  Subject: Re: [Nut-upsuser] Shutdown variables
       To: nut-upsuser at alioth-lists.debian.net


> ----- Message from Roger Price <roger at rogerprice.org> ---------
>    Date: Sun, 27 Nov 2022 13:53:40 +0100 (CET)
>    From: Roger Price <roger at rogerprice.org>
> Subject: Re: [Nut-upsuser] Shutdown variables
>      To: Simon Wilson via Nut-upsuser <nut-upsuser at alioth-lists.debian.net>
>
>
>> On Sun, 27 Nov 2022, Simon Wilson via Nut-upsuser wrote:
>>
>>> Per  
>>> https://networkupstools.org/docs/user-manual.chunked/ar01s06.html  
>>> 6.3, am I right in thinking, for my single server running NUT (in  
>>> standalone mode) with connected USB UPS:
>>>
>>> - when battery.charge reaches battery.charge.low: ups.status  
>>> triggers to "LB" and upsmon sets an FSD in motion
>>> - upsmon waits FINALDELAY 5 seconds, and calls my shutdown command  
>>> (which then in sequence does a clean shutdown of my VMs before  
>>> calling the 'real' shutdown command)
>>> - my server then shuts down and powers off
>>>
>>> Main question:
>>>
>>> "ups.delay.shutdown" - at what point does this variable kick in?  
>>> Is ups.delay.shutdown the period in seconds after FSD that the UPS  
>>> will hard-shutdown, i.e. I need to ensure that my server can  
>>> complete clean shutdown in that duration?
>>
>> Yes, you do need to give your server sufficient time.
>> My understanding is that the ups.delay.shutdown is overwritten by  
>> the offdelay option in file ups.conf.
>>
>> In the machine with which I type this, I have
>>
>> rprice at titan ~ upsc Eaton ups.delay.shutdown
>> 20
>> rprice at titan ~ grep offdelay /etc/nut/ups.conf
>>         offdelay = 30
>>
>> See https://rogerprice.org/NUT/ConfigExamples.A5.pdf chapter 2.5,  
>> and chapter 2.7 line 77.
>>
>> Roger
>>
>> _______________________________________________
>
>
> That is great, thank you. From reading that I also note the comment  
> that ondelay must be longer than offdelay.
>
> My server takes 90s to 110s to do a full shutdown... but most of  
> that is a scripted VM close before "shutdown -h +0" is finally  
> called. I will do a timed test to be precise on the weekend, but  
> until then I have put:
>
> [eaton5sx]
>         driver = "usbhid-ups"
>         port = "auto"
>         vendorid = "0463"
>         productid = "FFFF"
>         desc = "Eaton 5SX"
>         offdelay = 120
>         ondelay = 125
>         lowbatt = 30
>
> ...and restarted nut-driver. I then used upsc to confirm those  
> settings had applied, which they had.
>
> When I time it and see how long the actual post-VM-close shutdown  
> takes I'll be able to reduce those significantly.
>
> So, by my understanding from 2.6, my settings will trigger shutdown  
> at 30% (42 mins of net runtime for this rack), the shutdown process  
> will run on the server, including the nutshutdown command  
> (/usr/lib/systemd/system-shutdown/nutshutdown on RH), which will  
> then tell the UPS to power off at offdelay +2mins, with (if power  
> has restored) a further 5 seconds before it can come back on (to  
> ondelay).
>
> I think I have got it, thank you again. That link's a very useful resource.
>
> Simon.


----- End message from Simon Wilson via Nut-upsuser  
<nut-upsuser at alioth-lists.debian.net> -----


A followup question:

Noting in that document the following statement:

"[replbatt] The UPS needs to have its battery replaced. Not all UPS's  
can indicate this."

Can anyone advise whether the Eaton USB UPSs support that?  
Specifically mine is a 5SX 1750.

If they do not, what is the recommended way to check for health to  
maintain runtime and/or indicate time to change batteries?

Simon


-- 
Simon Wilson
M: 0400 12 11 16