Virtual machine hangs when powered on and running on snapshots

Products

• VMware vSphere ESXi

Issue/Introduction

The virtual machine (VM) runs on snapshots.

The VM hangs upon power-on (Guest OS logo appears, but no login prompt is displayed).

The VM cannot be powered off using command "localcli vm process kill -t hard -w <WorldID>", resulting in a "No such process" error; the ESXi host must be powered off and then powered on.

Once the ESXi host is powered off, the VM will be powered on by HA (High Availability) on another ESXi host, and this new ESXi host must also be powered off and then powered on again.

When the VM hangs, high DAVG/cmd values are observed for the datastore on which the VM resides (visible in esxtop → press u).

Environment

VMware vSphere ESXi 8.0.x

VMware vCenter Server 8.0.x

Cause

The VM fails to boot completely and hangs during the boot process; it cannot be forcefully killed. When the ESXi host is rebooted to restore normal operation, vSphere HA restarts the VM on another ESXi host, where it hangs immediately upon power-on.

Resolution

Disable vSphere HA for the cluster before powering off and restarting the ESXi host if the VM cannot be killed using the command "localcli vm process kill -t hard -w <WorldID>" .

With HA disabled, the hung VM will not fail over to other ESXi hosts in the cluster.

Reconfigure the VM to use its base disks instead of snapshots, and then power it on.