We have a 4 node Hyper-V cluster - I shut the vm's all down and powered off all the nodes last week for maintenance to the Blade Chassis. I powered the chassis and nodes back up, and powered on all vm's without issue. (FYI - the SAN was not shut down). Since then, a few VM's will all of a sudden go offline (yet they are still running) and connecting to the console of the vm shows the error: "Boot failure. Reboot and Select proper Boot device or Insert Boot Media in selected Boot Device". If i hit ctl+alt+del it will reboot and say the same thing, if I reset the vm it does the same thing, but if I POWER OFF the vm then power it back on, it will boot up just fine.
All vm's on this cluster node access the same SAN, the same LUN, so I don't think it's a SAN connectivity issue, even the Hyper-V Node itself boots from the SAN.
Why would these VM's intermittently stop or reboot to no disk like this? Any ideas on where to start looking would be greatly appreciated.