Why did ESXi Host reboot?

[CTSTech]

What are the steps I need to do to determine why an ESXi Host (5.0) rebooted?  This Host is on a free version of ESXi with no vCenter.

Thanks!

[a_p_]

First step is to check the event logs, to see whether it was a planned reboot. If it occurred suddenly (unplanned) you may check the host's management logs (e.g. iLO for HP, ...) if present. If the host doesn't provide a management interface, check for power failures, fan issues (temperature issues), ...

André

[CTSTech]

Thanks.  This was an unplanned reboot at 3am.  Can the ESXi logs tell me anything?

[a_p_]

If this was an unplanned reboot, the ESXi logs may end abruptly and then start again, so they may not be much helpful. Unless you have a management interface (as mentioned before) in your host, start checking the environment like UPS failures, power outages, ...

André

[zXi_Gamer]

Like a.p mentioned, in case of abrupt shutdown, the logs might not be available, however, you can take a look at /var/log/vmkwarning.log to determine if ESXi was  throwing some warnings

[zXi_Gamer]

Having said that, I would rephrase your question to "What made ESXi Host to reboot?"

[admin]

See this blog..

VMware KB: Determining why an ESXi/ESX host was powered off or restarted