Comment 5 for bug 1749838

(5:18:06 PM) mriedem: in the case of nova creating a port,
(5:18:17 PM) mriedem: it doesn't fail because nova orphans the port created from the first host, and creates a new port when going through the 2nd host
(5:18:29 PM) mriedem: so you end up with 2 ports for the instance that nova created even though you're only using 1
(5:18:47 PM) mriedem: in the case that you bring a port, nova doesn't unbind it before rescheduling, and that's why we fail to use it on the 2nd host