Building a Highly-Available PostgreSQL System with Tessell

Ensuring high availability in databases is essential for maintaining business continuity and performance, and Tessell PostgreSQL provides a robust solution for this purpose. The Tessell PostgreSQL High Availability (HA) system is structured around a three-node configuration, with each node playing a distinct role to enhance the system's resilience and efficiency. Node 1 acts as the primary database handling write operations, Node 2 serves as a synchronous standby for read-only operations and backup, and Node 3 functions as an observer within the etcd cluster to maintain quorum. The provisioning process involves launching these nodes, forming a quorum, and configuring Patroni for automated failover and switchover management. Failover scenarios are handled efficiently, ensuring minimal downtime and data integrity; for instance, if Node 1 fails, Node 2 is promoted to primary seamlessly. Maintenance tasks like patching are conducted with minimal downtime through parallel shutdown and synchronized patch application, maintaining system stability and data consistency. This setup ensures that Tessell PostgreSQL can deliver high availability and reliability, crucial for modern applications requiring consistent performance.