Cloud SQL gives you the flexibility to choose between three CA hierarchy options when you create a Cloud SQL instance

## Feature Cloud SQL gives you the flexibility to choose between three [CA hierarchy options](https://cloud.google.com/sql/docs/mysql/authorize-ssl#ca-hierarchies) when you [create a Cloud SQL instance](https://cloud.google.com/sql/docs/mysql/create-instance). You can choose between the per-instance CA (`GOOGLE_MANAGED_INTERNAL_CA`), the shared CA (`GOOGLE_MANAGED_CAS_CA`), or the customer-managed CA (`CUSTOMER_MANAGED_CAS_CA`) options as the server certificate authority (CA) mode for your instance. If you create an instance using the Google Cloud Console, then the shared CA option, (`GOOGLE_MANAGED_CAS_CA`), is the default configuration. If you create an instance using gcloud, the Cloud SQL Admin REST API, or Terraform, then the per-instance CA option (`GOOGLE_MANAGED_INTERNAL_CA`) is the default configuration. The shared CA and customer-managed CA options are now [generally available](https://cloud.google.com/products#product-launch-stages) (GA).