Openstack by designed is flawed and operations are not fully transactional which may leaves  states in different components out of sync. One example is frequent volume attachment/detachment, esp when network has glitches causing MQ unstable, and strange errors will start showing. This is because multiple components are involved, cinder, nova, and compute, where many states are maintained in multiple components. There is no master. Once a message got delayed or lost, they could easily run out of sync. There is no transaction manager coordinating the operation. In general operation across multiple components require a global transaction manager to guarantee the consistency. This also can be achieved  using 2PC which can be built into the framework.