Google Cloud Spanner Introduces Configurable Read-Only Replicas and Zero-Downtime Move Service

Google has introduced regional and multiregional configurations for Cloud Spanner, along with configurable readonly replicas, and zerodowntime instance moves. Cloud Spanner offers three types of replicas: readwrite, readonly, and witness.

The move to a new configuration is now possible without downtime. Custom deployments and additional read replicas can be added, and hourly compute and storage charges apply. The new feature requires opening a ticket with the Google support team due to current limitations.