You can now use the online migration option to migrate from Azure Database for PostgreSQL –Single Server to Flexible Server. Online migration is the ideal choice when you have large databases and require limited application downtime.
In online migration, applications connecting to your source instance aren't stopped while databases are copied to a flexible server. The initial copy of the databases is followed by replication to keep the flexible server in sync with the source instance. A cutover is performed when the flexible server completely syncs with the source instance, resulting in very minimal downtime to applications.
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