Some host power management events are handled by Oracle VM VirtualBox. The actual behavior depends on the platform:

• Host Suspends. This event is generated when the host is about to suspend, that is, the host saves the state to some non-volatile storage and powers off.

  This event is currently only handled on Windows hosts and Mac OS X hosts. When this event is generated, Oracle VM VirtualBox will pause all running VMs.

• Host Resumes. This event is generated when the host woke up from the suspended state.

  This event is currently only handled on Windows hosts and Mac OS X hosts. When this event is generated, Oracle VM VirtualBox will resume all VMs which are where paused before.

• Battery Low. The battery level reached a critical level, usually less than 5 percent charged.

  This event is currently only handled on Windows hosts and Mac OS X hosts. When this event is generated, Oracle VM VirtualBox will save the state and terminate all VMs in preparation of a potential host powerdown.

  The behavior can be configured. By executing the following command, no VM is saved:

  $ VBoxManage setextradata global "VBoxInternal2/SavestateOnBatteryLow" 0

  This is a global setting as well as a per-VM setting. The per-VM value has higher precedence than the global value. The following command will save the state of all VMs but will not save the state of VM "foo":

  $ VBoxManage setextradata global "VBoxInternal2/SavestateOnBatteryLow" 1
  $ VBoxManage setextradata "foo" "VBoxInternal2/SavestateOnBatteryLow" 0

  The first line is actually not required as by default the savestate action is performed.