Reliable Data Store
Problem
Stateful Microservices are commonly associated with dependencies on external data stores. These dependencies often introduce bottle necks in terms of performance and availability as the data source can act like a single point of failure. This problem has enhanced impact where multiple instances of a service co-exists at a given point. Maintaining high availability of the data store becomes expensive as the data grows. The following diagram illustrates a system with a centrally externalized data store:
Reliable data store (Problem)