A UPS Restart of Server 2008 R2 running Hyper-V

Question

Hello

Can anyone help?

We have a Dell PowerEdge T620 running Server 2008 R2 with two virtual servers (SBS 2011 and Server 2008 R2) in Hyper - V. The PowerEdge is
attached to a Dell UPS Rack/Tower 2700w 3U.

Dell UPS Node Manager has been used to configure the UPS. The setup facilitates graceful shutdown the virtual servers before Hibernating the host
server. The intention is that in a power outage the servers are shutdown when the battery is depleted and then restarts when power is restored.

However, according to Microsoft, Hibernate is disabled where Hyper-V is used. The impact is that the UPS attempts Hibernation, fails and enables shutdown. It is then necessary for a manually switch-on of the server. The virtual servers will then automatically restart.

It is highly undesirable to have to manually switch on the host server. Does anyone know how a restart can be enabled?

Thank you in advance.

theflash1932 · Accepted Answer

Thanks for the clarification ... I figured that was what you were talking about but just wanted to be sure :)

Yes, your plan should be fine, as long as the Test Shutdown actually simulates no power (battery drain) and not just sending the Shutdown signal.

theflash1932 · Answer

The option is in the BIOS Setup F2 ... under System Security.  Set AC Power Recovery to 'On'.  The default is 'Last', so if your UPS gracefully shuts down your host, then AC power is lost, when AC power is restored, the 'last' state was Off, so it stays off.

RMSScotlandLtd · Answer

Thank you for your help. We will make the alteration when it is possible to restart the server and post the result

theflash1932 · Answer

You can make this change from OMSA (OpenManage Server Administrator) ... OMSA, System, Main System Chassis, BIOS, Setup tab, change AC Recovery to On, and Apply.

RMSScotlandLtd · Answer

Thank you for your help 'theflash1932'. We have followed your instructions and can make the change. Unfortunately we cannot verify the effectiveness until we test the UPS shutdown of the system. This will be arranged and following testing we will post the result.

theflash1932 · Answer

I tested it on a server I have here (2950) and the change was effective immediately, so it should be fine, however, I do understand your need to confirm it.

RMSScotlandLtd · Answer

We have made the change to the BIOS, setting the AC Power Recovery to On. This required a restart to take effect. Unfortunately when we then ran the UPS Test Shutdown the server did not restart and a manual switch-on was required.

Are there are further solutions?

theflash1932 · Answer

No ... that is the only way to enable this functionality.  After the shutdown, did you allow the UPS battery to completely drain, so that the AC power sensor in the server would have sensed ZERO power?  This setting is valid ONLY if the power supply LOSES AC power completely and is only triggered only once power is restored.  Pulling the plug would be an alternative to letting the battery drain completely.

theflash1932 · Answer

'pull the plug' 're-insert the plug' Are you talking about the plug to the server or the plug to the UPS?

RMSScotlandLtd · Answer

No we had not removed the plug during the test.

To clarify, should we:

1.Pull the plug

2.In the UPS node manager, click Test Shutdown

3.Wait for the shutdown

4.Re-insert the plug

Then expect the system to restart?

Thank you for your help theflash1932

RMSScotlandLtd · Answer

Sorry for not being explicit. I was meaning the power plug to the UPS. The server receives its power via the UPS, I would not be detaching this plug because clearly the server would lose all power and the UPS could not supply the backup power as it is designed to do so.

To test the BIOS configuration and the UPS setup is working correctly should we take the following steps:

1.Detach the power plug to the UPS, to simulate a power cut

2.On the host server - In the UPS node manager, click Test Shutdown

3.Wait for the shutdown of virtual servers and host server as setup in Node manager, for a graceful shutdown

4.Re-insert the power plug to the UPS, to simulate the end of the power cut

Then expect the host server to automatically restart (because of the BIOS AC Power Recovery is set to On), followed by the virtual servers (as is currently setup)

RMSScotlandLtd · Answer

Thanks again theflash1932 - We will arrange a futher test and report back following it

RMSScotlandLtd · Answer

We were able to run the test last night, I am glad to say it was a success. Thank you theflash1932, your configuration settings have enabled us to achieve the desired result.

theflash1932 · Answer

Glad it worked for you!

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A UPS Restart of Server 2008 R2 running Hyper-V

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