- Typically you will want the MIXED format (vs. statement-based and row-based). Mixed format is kind of the best of both worlds (safer than statement-based but doesn't generate as much data as row-based). - In Aurora, gtid_mode in 5.7 is defined as OFF_PERMISSIVE, while in 5.6 it is OFF. Theoreticaly, according to [MySQL :: MySQL 5.7 Reference Manual :: 16.1.4.1 Replication Mode Concepts](https://dev.mysql.com/doc/refman/5.7/en/replication-mode-change-online-concepts.html), you should be able to replicate from an OFF_PERMISSIVE in 5.7 to a 5.6 in OFF, but it's not true: [MySQL Bugs: #75769: 5.6 with GTID\_MODE=X cant connect to 5.7.6 with GTID\_MODE=X\_PERMISSIVE](https://bugs.mysql.com/bug.php?id=75769).