One of the most critical parts of OpenStack is the database. Usually, MySQL is used when there is no special configuration to prepare specifically for OpenStack to run smoothly and satisfy its multiple services. On the other hand, it becomes pretty tough to maintain your MySQL databases when your cloud keeps growing. Database inconsistency constitutes one of the biggest challenges when running OpenStack in production. For example, it could happen that you have disassociated a network from an instance but the status in the database has not been changed. Nova claims that the network is associated within the instance, while Neutron claims the opposite. In this case, you will have to edit the database manually and change the state in the database. In rare cases, manual intervention can be error-prone. Generally, it is much more difficult to keep consistency when other changes are being performed in a given database table. All of this points to another database...