This happens occasionally and never got an answer to it. I have lots of VM's running on this host (4 node cluster). But occasionally a backup of a particular SQL VM results in the SQL VM being down and the ESXi 6.0 server being unresponsive (timeouts performing tasks) in vSphere (still connected though?) and the KVM console won't go past logon. I SSH'd and it says the VM's parent pid is not running, but a ps | grep VMX shows it there. I tried to restart services, but it seems to get to snmp and then just sits there. I assume its at the vpxa service and trying to stop, but can't tell. Can't even Ctrl-c out.