Gracefull shutdown of UPS and delays ?

[BillP]

Hello,

I would like to know which parameter defines the time between the following message in logs "UPS: A graceful shutdown process is being used to shut down the load equipment before the UPS turns off. " and the extinction of the UPS.

Where to find it on the web interface of the management card ?

Regards.

[BillP]

Hello,

I would like to know which parameter defines the time between the following message in logs "UPS: A graceful shutdown process is being used to shut down the load equipment before the UPS turns off. " and the extinction of the UPS.

Where to find it on the web interface of the management card ?

Regards.

[Erasmus_apc]

There are two parameters that pertain to this question.

The first is the "Maximum Required Delay", which is in the NMC under "UPS->Configuration->Shutdown". This setting is the maximum amount of delay that any one PCNS client needs to complete its shutdown sequence. It is by default the "Low Battery Signal" setting, but also includes an added 2 minute delay (not configurable) to ensure against any accidental dropped loads. The value would only be different if one PCNS client had a command file set up to run during its shutdown procedure. The NMC will wait for this full delay to expire before issuing a shutdown command to the UPS.

The other parameter is "Shutdown Delay", which is located in the same area in the NMC interface. This is the amount of time that the UPS will wait to shut down after receiving a shutdown command from the NMC.

Basically, the PCNS client starts a shutdown sequence, and the "Maximum Required Delay" begins to time down (calculated time + 2 minute buffer). While this is counting down, the client operating systems are shut down, and this is when you will see your computers turn off, etc. Once the Max Req. Delay has been met, including the 2 minute buffer, this is when the UPS turn off command is sent from the NMC to the UPS. Once this command is sent, THEN the "Shutdown Delay" setting is put into use, and the UPS waits this amount of time before actually turning off.

[BillP]

It is what i understood. But :
- i set "Low Battery Duration:" (save value indicated by "Maximum Required Delay:") to 5 minutes.
- i set "Shutdown Delay:" to 10 seconds.
- At the "Low Battery" signal PCNS client are configured to make a shutdown. Excepted 1 client, all of them are configured to wait 1 second after the "Low Battery" signal to make shutdown. One client is configured to wait 1 minute before to shutdown. Only this client have the checkbox "Turn off the UPS after the shutdown finishes" checked.

When a make a test, i unplug the input power. Then after a moment the UPS send the "Low Battery" signal (when the value of "Runtime Remaining" reach the value of "Low Battery Duration". All clients make shutdown gracefully. But UPS don't switchoff unil it reach 0 seconds of "Runtime Remaining".

I don't understand.

Message was edited by: fc4acp

[Erasmus_apc]

There is no way to configure the low battery shutdown setting in PCNS. The UPS communicates to PCNS that the low battery signal threshold has been hit, and PCNS begins an immediate shutdown. I'm not sure which setting you are referring to, but the PCNS behavior for a low battery shutdown is hard coded, again, there is no way you can change it in PCNS. So, which setting are you referring to? Can you post a few screenshots?

[BillP]

Here some screen shots.

alpha is the hostname. Some comments :
- picture 2 : show the parameter "Battery: Discharged" checked on all clients.
- picture 3 : show the effect when the parametter "Battery: Discharged" is reached.
- picture 4 : show what to do when the client shuts down.

Except one client, all of them are with these parameters. Only one client have :
- in the picture 3 a time of 60 seconds.
- in picture 4 the checkbox "Turn off the UPS after the shutdown finishes" checked.

And i thought that the "Turn off the UPS after the shutdown finishes" checkbox send a signal to UPS to shut down himself.
But UPS never shuts down when this client is off.

Message was edited by: fc4acp

[BillP]

This time set "Low Battery Duration" to 14 minutes. To set this parameter to this value sets the parameter "Maximum Required Delay" to the same value.

Then i unplug the input power line.
When the value of "Runtime Remaining" is under 14 minutes, the "low battery" staus is displayed by the NCM web interface. Clients receives the signal and makes a gracefull shutdown.
After this, the message "Graceful Shutdown Initiated. A graceful shutdown process is being used to shut down the load equipment before the UPS turns off. Initiated by PowerChute ns from IPAddress_of_client_with_picture4_checked"
At this time with all client off, the charge is lower. The "low battery" message disappear on the NCM web interface.
After a moment the "low battery" comes back.
I have to wait "Low Battery Duration" + 2 minutes + "Shutdown Delay" minutes, then the UPS if off.

I would like to be able to make UPS shutdown immediately (excepted the 2 minutes added forcibly) when the message "Graceful Shutdown Initiated" appear.
Is it possible ?

[Erasmus_apc]

The battery discharge event is an online only event, generally. It is an event generated online when the unit knows that IF the power fails and the unit has to go to battery, then a low battery signal would be immediately generated. It is not the same as a low battery signal.

I usually do not give this information, but it is not particularly in depth in terms of proprietary coding and is rather helpful. See the attached files for the shutdown behaviors for a regular event (such as being on battery for 2 minutes, etc.) versus the shutdown behavior for PCNS when the unit is given a low batt signal on battery.

The closest you will get to an "immediate" shutdown, is leaving PCNS totally unconfigured, setting your low battery shutdown setting for something reasonably high, that will allow your servers time to actually shut off, and setting the NMC delay values to 0. You will still see some delay between that initial message and the UPS finishing its shutdown cycle since you have multiple clients, but it will skip the Maximum Required delay + 2 minutes and is the most we can offer. Again, refer to the PDFs I have given to make your best decision.

[BillP]

I am surprised that my need is special.

The input power is suddenly off. So, from now UPS use batteries. After a moment, the batteries have a low level and a shutdown is needed.
I thought that when the shutdown of UPS is needed i have to be pretty quick.

[Erasmus_apc]

It's not special per-say, I think I am explaining this properly. If you set no shutdown events on PCNS, PCNS will only shutdown in the case of a low batt signal from the UPS when on-battery. The shutdown timer will become the low-batt signal time instead, without a 2 minute buffer, and by default, the shutdown signal will be sent when the low battery signal time has been met, and the UPS will turn off (assuming you have no shutdown delay set). You can work around this by setting one of your servers (the one that takes the longest to shut down) to send a shutdown signal to the UPS when its shutdown has completed. To do this you will need to check the "Turn off the UPS after the shutdown finishes" box in the Configure Shutdown screen. Keep in mind that the NMC will wait until all PCNS clients have been shut down to actually begin its own shutdown/turn off sequence. You will also need to turn off the shutdown delay (set it to 0). So now the behavior of the shutdown would be:

-Low Batt Signal received
-servers begin immediate shutdown w/ no delay
-once the server that has the Turn Off option checked shuts down, it will signal the UPS to turn off
-the UPS should turn off once all PCNS clients have verified shutdown, since there is no shutdown delay

Keep in mind the verification for the shutdown command from the PCNS clients and the NMC making sure all the clients have shut down may take a short amount of time. There is no way to make the UPS immediately shut down as soon as soon as "Graceful Shutdown Initiated" occurs in the logs, since generally this message only signals the beginning of a shutdown process.

[BillP]

Well.
I set no shutdown events on PCNS.
I turned off the shutdown delay.

With my load the "Runtime Remaining" 's value is just upper than 14 minutes.
I set the "Low Battery Duration" 's value to 14 minutes to permit a quick test. Then i unplug the input power cordon.
With this setup, in few seconds the "low battery" is reached.
At this time all my PCNS clients make shutdown and the "Runtime Remaining" 's value jump to 18 minutes.
The UPS shouts that he initiates a graceful shutdown.

At this time, to see the UPS to shut down, i have to wait 14+2 minutes. Is it possible to make this waiting time shorter ?

Except by setting "Low Battery Duration" 's value to 5 minutes.

Message was edited by: fc4acp

[BillP]

Techie I already saw this picture. It was helpfull.

[Erasmus_apc]

fc4acp wrote:
Well.
I set no shutdown events on PCNS.
I turned off the shutdown delay.

With my load the "Runtime Remaining" 's value is just upper than 14 minutes.
I set the "Low Battery Duration" 's value to 14 minutes to permit a quick test. Then i unplug the input power cordon.
With this setup, in few seconds the "low battery" is reached.
At this time all my PCNS clients make shutdown and the "Runtime Remaining" 's value jump to 18 minutes.
The UPS shouts that he initiates a graceful shutdown.

At this time, to see the UPS to shut down, i have to wait 14+2 minutes. Is it possible to make this waiting time shorter ?

Except by setting "Low Battery Duration" 's value to 5 minutes.

Message was edited by: fc4acp

Did you check on the "Turn Off UPS" checkbox that is in the PCNS Shutdown Configuration menu on one of the PCNS clients communicating with this NMC? As I have said before, with a low battery shutdown, the 2 minute buffer time is not used. If your runtime changed this is not the fault of PCNS or the NMC, it is just the unit recalculating accurate runtime on battery.

[BillP · Accepted solution]

Thank you.