SQL Server 2016 RC0 関連の情報を眺めていて知ったのですが、RC0 では、セカンダリの同期方法として「SEEDING_MODE = AUTOMATIC」という方法が追加されています。
High Availability Enhancements
[RC0] Direct seeding allows a secondary replica to be automatically seeded over the network (rather than manual seeding that requires a physical backup of the target database to be restored on the secondary). Direct seeding is specified by setting SEEDING_MODE=AUTOMATIC in the CREATE AVAILABILITY GROUP (Transact-SQL) or ALTER AVAILABILITY GROUP (Transact-SQL) statements. You must also specify GRANT CREATE ANY DATABASE with ALTER AVAILABILITY GROUP (Transact-SQL) on each secondary replica that is used with direct seeding.
これについて、少しまとめてみたいと思います。