This guide covers the automatic in-place upgrade path for a PostgreSQL major version upgrade when using the CloudNativePG (CNPG) operator. CNPG natively supports offline in-place major version upgrades using PostgreSQL's pg_upgrade --link. This is triggered automatically when xl kube upgrade with PreservePvc=Yes applies a new Cluster template that bumps the imageName to a higher major version against an existing running cluster.
This guide covers the manual steps required to upgrade PostgreSQL across a major version when using the CloudNativePG (CNPG) operator-based PostgreSQL installation — i.e., when PostgreSQL is managed through the experimental postgresql-operator and postgresql-cluster rather than through the Deploy CR's built-in spec.postgresql keys.
PostgreSQL cannot be automatically upgraded during an operator-to-operator or Helm-to-operator upgrade due to incompatible data formats between different PostgreSQL server versions. In such cases, a manual upgrade is necessary. The process involves first backing up the PostgreSQL data, then upgrading to the new PostgreSQL version, and finally restoring the data in the upgraded version.
This guide covers the manual steps required to migrate from the Bitnami chart-managed PostgreSQL and RabbitMQ installation (the default up to and including operator 25.1 releases) to the operator-managed equivalents: