I've come across a very serious bug. I've installed ESXi (Label_version 4.0.0 | 171294 However, I've managed to track down the problem a bit. I can reboot the host fine until I've created a new datastorage (first obligatory one after installation). After creating the storage, I always get a "missing operating system" after reboot. I can also reboot the host without problems (even after creating the datastorage) when I'm rebooting it from the console, that is, from a keyboard and monitor connected directly to the server.
I'm now on 3.5 update 4, which seems to work fine (reboot, shutdown and so on tested).
From console you can reboot the host and boot up successfully, right?
But, from vSphere client, when reboot the host, server can not find any operating system to boot up?
Sounds like a boot drive reordering problem. I've seen it here with installing on a machine with 4 disks as well.
By changing the order of the boot drives in the BIOS i could get around it.
Hope this helps,
VI-Toolkit & scripts wiki at http://www.vi-toolkit.com
Actually the DL180 G6 is on the HCL not the G5. That shouldn't mean it will have issues but. . . . How is the array configured? Are you using the HP version of ESXi 4? I would try installing to a USB flash disk. Should be an internal USB port for it. A CD install directly to the USB stick is a supported install option. Installing to USB means you have separated the OS from the datastore. Reduce the risk of overwriting or corrupting the datastore during upgrades or reinstalls.