Semab Tariq knows that an application cannot serve two masters:
In this blog post, we will try to explore a critical failure condition known as a split-brain scenario that can occur in PostgreSQL HA clusters. We will first see what split-brain means, and then how it can impact PostgreSQL clusters, and finally discuss how to prevent it through architectural choices and tools available in the PostgreSQL ecosystem
Click through for an explanation of split-brain and what can cause this problem. Additionally, Semab includes several tips on how to limit the likelihood of a split-brain scenario occurring.