Migration service for Postgres
Currently the only way to migrate Postgres into Cloud SQL is to dump and restore. This necessitates downtime. We need a way to migrate Postgres DB without downtime.
So in practice GCP needs to do a managed Bucardo service to transfer data into Cloud SQL, and subsequently we can switch the Replica status to Master status.
Cloud SQL and the Database Migration Service (DMS) offer managed migration support for PostgreSQL in Private Preview. To determine if DMS will work for your database migration, check out the website:
To learn more, check out our blog post: