'Powers on all VMs under specified node. VMs need to be This operation
is allowed only when the vApp/VM is powered on.
:param  node: The node to be powered off
:type   node: :class:`Node`
:rtype: :class:`Node`'

def ex_power_off_node(self, node):

    return self._perform_power_operation(node, 'powerOff')
