Available runtime has been exceeded which causes server to reboot

[Anonymous user]

Hi all,

PCNS 4.1.0
AOS  3.7.3
SUMX 3.7.2

2 x Smart-UPS RT 3000 XL each with AP9618 NMC

PCNS installed on 4 Windows 2012 R2 servers (in redundant configuration).  VM/SCVMM is not used. 3 servers are configured to shutdown when 'UPS On Battery', the 4th when 'Runtime exceeded' with a delay of 120 seconds.

Low battery on both is configured to 2 minutes and Shutdown delay is 20 seconds on each. Runtime remaining is 22 & 25 minutes on the UPS'.

Everytime I reboot a server, a 'Available runtime has been exceeded' event is logged. This causes the server with the Runtime exceeded shutown event to fire.  I have removed it from the node, but still keep getting the runtime has been exceeded error.  Event log attached.

Is there any idea what to do to prevent such behavior?

Tony

[BillP · Accepted solution]

Hi,

This issue is discussed in the User's Guide on page 34 and in PCNS help files.

Below is from the User's Guide:

Available runtime has been exceeded

For both conditions below, the “total shutdown time” includes the following durations:

• Shutdown command file duration
•  Built-in duration of 2 minutes (this consists of a 10 second OS shutdown duration and a 60 second OS shutdown duration; rounded up)

This event occurs with either of the following conditions:

Condition 1. When the total shutdown time required by PowerChute is greater than the Low Battery Duration minus two minutes configured for the UPS. In the event of a low battery condition, PowerChute will not have enough time to complete the shutdown sequence before the UPS powers off. For example, if the total shutdown time required is 3 minutes and Low Battery Duration is 4 minutes, the Available Runtime has been Exceeded event will be triggered.

Resolution: Increase the Low Battery Duration value on the NMC using Configure - Shutdown or decrease the shutdown durations being used by PowerChute.

Condition 2. When the shutdown duration configured for the UPS On Battery event plus the total shutdown time required by PowerChute is greater than the Runtime Remaining on the UPS minus two minutes. This condition can be caused by having too great a load on the UPS when the battery is fully charged.

Resolution:

1. Remove some equipment from the UPS to increase the available runtime.

2. Decrease the shutdown duration time for the UPS On Battery event.

3. Decrease the command file execution time using the Shutdown Settings screen. This event is logged and event actions are carried out even if it occurs on a single UPS in a Redundant or Parallel UPS configuration.

From reading your post I suggest increasing the low battery duration to 5 minutes. That should resolve the issue unless you have a delay set up that is not mentioned in the post. 

[Anonymous user]

Thanks Bill - have made the changes as above.

Can I ask a question about redundant mode?

If we have a power outage the UPS's take over.  In redundant mode, UPS1 runs takes all the load and runs until the battery runs out and then UPS2 takes over the load.  So I should have about 40 minutes runtime given the above figures (22 + 25), is this a correct overview?

Cheers
Tony

[roger_apc]

Hi Tony,

If the servers are dual corded, I would connect one cord to each UPS.  In normal operation, the load will be shared between the UPS units.  In this configuration, if either UPS were to fail, the servers would still be powered.  Automatic shutdown becomes a bit more complicated.  You would need to start your shutdown process when the UPS with the shorter runtime is about to fold.  However, this would have the side benefit of providing a bit of a pad against an extended shutdown period.

In our enterprise, we use rack mounted ATS units for any device that is single corded.

Cheers,