Introducing Stolon: Cloud‑Native High‑Availability for PostgreSQL

Stolon is an open‑source, cloud‑native manager that enables high‑availability PostgreSQL deployments across containers, Kubernetes clusters, public IaaS, and legacy infrastructures.

Key Features

Uses PostgreSQL streaming replication.

Works with any topology; prefers consistency over availability while striving for maximum uptime.

Kubernetes integration provides automated PostgreSQL HA.

Supports etcd, Consul, or the Kubernetes API server as the distributed store for leader election and cluster state.

Offers asynchronous (default) and synchronous replication modes.

Cluster can be set up within minutes.

Simplified cluster management.

Integrates with preferred backup/restore tools for point‑in‑time recovery.

Provides a standby cluster for multi‑site replication and near‑zero‑downtime migrations.

Automatic service discovery and dynamic reconfiguration handle changes to PostgreSQL and Stolon process addresses.

Supports rapid instance resynchronization with pg_rewind against the current master.

Architecture

Stolon consists of three main components:

Keeper : runs a PostgreSQL instance and converges it to the cluster view calculated by the sentinel.

Sentinel : monitors keepers and proxies, discovers failures, and computes the optimal cluster view.

Proxy : serves as the client entry point, routing connections to the current PostgreSQL master and terminating connections to the former master.