Need help in understanding shutdown sequence.

[Anonymous user]

Hi!

I have APC 5000XLI UPS with AP9619 NMC and some servers connected to it. There are clients (PCNS and apcupsd) installed on servers.

At now UPS configured with these defaults:

Start of Shutdown
Low Battery Duration: 2 minutes
Shutdown Delay: 20 seconds
Maximum Required Delay: 2 minutes
Basic Signaling Shutdown: Unchecked
Basic Low Battery Duration: 150 seconds
Duration of Shutdown
Sleep Time: 0.0 hours
End of Shutdown
Return Runtime Duration: 0 seconds
Return Delay: 10 seconds

I need to understand the shutdown sequence logic based on that settings:

When power fails the UPS goes on battery, when 4 (2+2) min remains it signals clients to shutdown, waits 4 min and 20 sec and turns off. Is that right?

What happens if power returns after NMC had sent shutdown signal?

Thank you in advance.

And sorry for my English.

Message was edited by: dfx

[BillP]

The NMC will send the command to all clients to shutdown at the low battery duration mark, regardless of how long the servers actually take to shutdown. With the LBD set to 2 minutes, when 2 minutes of runtime remain on the battery, the NMC will command everything to shutdown. UPS will shutdown 2:20 after that (when incorporating the shutdown delay).

If your servers take 10 minutes to shutdown, set the LBD to 11 minutes, yes.

The UPS doesn't really "wait" for any response from the server unless you have the box checked in PCNS to shutdown the UPS after that server is done shutting down. Unless that is enabled, it will turn off when the NMC tells it to, not the server.

We have a [specific version of PCNS|http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=SSPCNSV] that's designed for VM machines that you might be interested in taking a look at.

"So for example, if I use 11 minutes for LBD. At 11 minutes, command is sent, then based on the shutdown delay setting it would then wait for that to expire and then go offline?"
- Yes.

[Anonymous user]

Hi!

I have APC 5000XLI UPS with AP9619 NMC and some servers connected to it. There are clients (PCNS and apcupsd) installed on servers.

At now UPS configured with these defaults:

Start of Shutdown
Low Battery Duration: 2 minutes
Shutdown Delay: 20 seconds
Maximum Required Delay: 2 minutes
Basic Signaling Shutdown: Unchecked
Basic Low Battery Duration: 150 seconds
Duration of Shutdown
Sleep Time: 0.0 hours
End of Shutdown
Return Runtime Duration: 0 seconds
Return Delay: 10 seconds

I need to understand the shutdown sequence logic based on that settings:

When power fails the UPS goes on battery, when 4 (2+2) min remains it signals clients to shutdown, waits 4 min and 20 sec and turns off. Is that right?

What happens if power returns after NMC had sent shutdown signal?

Thank you in advance.

And sorry for my English.

Message was edited by: dfx

[Erasmus_apc · Accepted solution]

If you do not set up any shutdown settings on PCNS the software client will rely entirely on the low battery duration setting for deciding when to shutdown. A low battery shutdown starts when the amount of runtime remaining = the LBD setting. There is no added delays except for the shutdown delay during a low battery shutdown. This means when you have 2 minutes left of runtime, that is when the shutdown process occurs, and so you will have a total of only 2 minutes for the attached load to shut down. If your load is able to shut down within 2 minutes, then the NMC will command a UPS shutdown, the UPS will wait 20 seconds (shutdown delay), and then turn off. Once the actual shutdown command process from PCNS is issued for a shutdown, a return to power has no bearing on what happens, a shutdown is imminent.