DocumentDB on Kubernetes: Resilient, Highly Available Databases with Automatic Failover

DocumentDB is an open-source MongoDB-compatible database built on PostgreSQL that provides a familiar interface while leveraging PostgreSQL's reliability and extensibility. The DocumentDB Kubernetes Operator brings this database to Kubernetes environments by extending the platform with custom resources. The operator manages DocumentDB clusters declaratively, handling deployment, scaling, upgrades, and high availability scenarios automatically. The DocumentDB Kubernetes Operator provides multiple levels of high availability, each addressing a different failure domain. Local HA deploys multiple database instances within a single Kubernetes cluster with automatic failover in seconds, protecting against pod and node failures. For further resilience, you can configure availability zone spreading so that replicas land in different AZs, allowing the cluster to survive a full zone outage without manual intervention. Beyond a single cluster, the operator supports multi-region HA across Azure re