Comment 5 for bug 1590490

There are several error messages in node-4 compute log right before failure:

2016-06-08 15:34:03.958 5121 ERROR nova.compute.resource_tracker [req-50332790-7a77-474d-8b8b-0db77b3648b6 - - - - -] Migration for instance bac44ad7-eaf8-4d9c-b62e-d8537f107193 refers to another host's instance!

so probably the message was dispatched to another host.