vmware host is rebooting every other Thursday around 4AM. Have no idea what is causing it.

[Psintegrated]

We recently installed a new Vmware host and since installing it, it has been rebooting at 4AM every other Thursday.  For the life of me I cannot figure out what is causing this.  Here is what I have so far: 

Server information:

VSphere 5 Essentials

Lenovo ThinkServer RD330

Synology Diskstation SAN

We have 2 hosts and the other one does not do this. The VM servers on the host get hard shutted down leaving a Critical kernel power error in the event viewer.  They automatically turn back on a few minutes later.  I can't tell if the whole host is rebooting or not.

Syslogs for a few hours before and after - http://pastebin.com/BRNuDZCy

Events - http://i.imgur.com/LcNx0UR.png

System event log - http://i.imgur.com/cX9z1g0.jpg

Thank you for any help, I'm truly stuck on this. 

-Jeff

[Gav0]

Do these servers have any out-of-band management utility such as ILO or iDrac that you could pull some logs from?

Are both servers in the same cab?  Do they share a common power supply?

[Gav0]

Looking at your System Event log it appears your host is definitely rebooting - note the Power-off (S5) condition:

http://www-01.ibm.com/support/docview.wss?uid=swg21506225

[Psintegrated]

Thanks for the response.

If the server does, I have no set it up.  I'm not sure what the equivalent to iLO is on lenovo. 

Both servers are in the same rack.

Both server share the same UPS.