Maybe someone found a bug like this in your OpenStack, when you created an instance,
error: Traceback (most recent call last): File "/usr/lib/python3/dist-packages/nova/conductor/manager.py", line 705, in build_instances raise exception.MaxRetriesExceeded(reason=msg) nova.exception.MaxRetriesExceeded: Exceeded maximum number of retries. Exhausted all hosts available for retrying build failures for instance 051c6ae4-02cd-497e-9544-a4d4c713c069.
