[Nut-upsuser] UPS Reboots when Pi Reboots!

[Roger Price]

On Sun, 16 Aug 2020, James Fischl wrote:

> Thank you Roger, I appreciate the response. I'll have to check my commands, I 
> believe I started it with those systemctl commands you provided. What I can 
> say is that oddly enough after completing the server config and after two more 
> reboots a reboot of the Pi doesn't seem to be causing the UPS to reboot 
> anymore. I have a bit more config to do on slave machines tomorrow but after 
> that I'll do testing - including pulling the plug - and see what happens. 

One problem that NUT users have is that they correctly install and configure 
NUT, but then enter a command such as "shutdown -h now" to test the setup.  The 
effect is for the box to shutdown and then restart shortly afterwards, despite 
the "-h".  The true test is to pull wall power.

> I do recall from reading the documentation that the master can initiate a 
> reboot of the UPS and that in a shutdown event I believe it's supposed to do 
> actually trigger a delayed shutdown to occur after the master's own power-off. 
> How that gets mixed up with an OS reboot is odd to me...perhaps something 
> scripted in relation to the NUT service stopping? 

It is important to be clear as what is shutting down.  A possible sequence is:

  1. Wall power fails.  The UPS beeps.
  2. Master calls for server shutdown
  3. Server shuts down, leaving the UPS beeping.
  4. After a ups.conf specified delay the UPS turns off its power outlets and
     stops beeping. This is refered to as "delayed UPS shutdown".
  5. Later, wall power returns and is detected by the UPS.
  6. The UPS turns on its power outlets.
  7. The server reboots.

Roger