Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

The system started resetting itself exactly every 2 hours. These are the messages in the iLO2 log:

Informational iLO 2 03/07/2010 20:40 03/07/2010 20:40 1 Server power restored. Caution iLO 2 03/07/2010 20:40 03/07/2010 20:40 1 Server reset.

It's not an ASR reset (that would show in the log) Redundant power supplies, swapped but no change. Turned off all virtual machines (i.e. now only running hypervisor) but not OK Boot HP smartstart diagnostics disk, ALL OK Diagnostic disk reports no errors Went back to booting Hypervisor and the problem is back.

Seems the hyper-V system disk has got a time based program (virus) causing the reset. I thought the hypervisor had a small attack surface and should be OK. All virtual machines (SBS2008, Win7 and Win XP) and network computers are protected with TrendMicro WFBS.

I am about to rebuild the disk (I have backups) but wondered if there were any suggestions to try first???

share|improve this question
I'd have thought that those messages indicated that the ILO was telling you that the physical power supplies were losing supply power, not a controlled shutdown from within the OS. Are you 100% sure that there isn't something going wrong with your AC\UPS supply? I'm not familiar with ILO logs though - do you see the same log entry if you forcibly reset a server? – Helvick Mar 7 '10 at 11:41
I can not believe it's a virus in the hypervisor. Could it be the UPS software is flawed and telling it power is about to fail? I'd disable all UPS and power sensors & drivers. – Knox Mar 7 '10 at 11:49
A forced reset say: Caution iLO 2 03/07/2010 18:37 03/07/2010 18:37 1 Host server reset by: setup. The power supplies are OK ... I can remove either and there is no restart. – GT Mar 7 '10 at 11:54
One power supply is direct from the AC, the other via the UPS. I am not using management software for the UPS. – GT Mar 7 '10 at 11:55
Seems similar to this… . Either a hardware fault or a problem with the OS Agent's handling of hardware alerts. Have you escalated this to HP yet, seems very likely to be a known issue. I know early versions of the HP G6's had some power\power management deficiencies so it definitely worth calling them. – Helvick Mar 7 '10 at 12:10

I had something similar happen on a ML350G5. It turned out that my power supply backplane needed to be replaced. I suggest calling support and going through it with them. It took a very short time to determine that this was the problem.

share|improve this answer
up vote 0 down vote accepted

This may be unrelated, but if you happen to have installed the RC of Hyper-V server 2008 R2, the expiration was on March 1st I believe. After the RC version expires, it begins to reboot every two hours.

share|improve this answer
Yes I WAS running the RC version, even though I had the final version ready to load (never got a round to it). Silly me thought there would be some kind of Microsoft message to tell me if the RC had expired, not just re-boots! Just finished loading the new version and it seems OK now. Thanks all for the troubleshooting ideas. – GT Mar 8 '10 at 11:04

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.