Comment 3 for bug 1696025

hi ,Sylvain Bauza：
    i found this WARNING in my log.
2017-06-27 19:52:21.461 5710 WARNING nova.compute.manager [-] [instance: ccc70205-f743-4667-83f6-eacbed978cfa] Instance shutdown by itself. Calling the stop API. Current vm_state: active, current task_state: None, original DB power_state: 4, current VM power_state: 4
2017-06-27 19:52:21.462 5710 DEBUG nova.compute.api [-] [instance: ccc70205-f743-4667-83f6-eacbed978cfa] Going to try to stop instance force_stop /usr/lib/python2.7/site-packages/nova/compute/api.py:2086
     thanks.