Management API requires writing to the App-Services database
The Management API sometimes writes documents to the App-Services database for internal purposes, and it therefore assumes that the App-Services database is writable. On each cluster in which the Management API runs (which might include a replica cluster), it requires a writable view of the App-Services database. The App-Services database is used to store data used by various MarkLogic applications, such as Query Console. For these reasons, MarkLogic recommends that you do not replicate the App-Services database using database replication. If the App-Services database is not available, it falls back to the schemas-database configured for the schemas-database of the App Server under which the Management API is running.