RDS MariaDB enforces the following constraints to ensure service stability and security. Review these limits before you design your application or migrate an existing database.
| Item | Limit |
|---|---|
| Parameter modification | Modify parameters through the RDS console or API. Some security-related parameters are locked and cannot be modified. For details, see Use the console to set parameters. |
| Root and sa accounts | The root and sa accounts are not available. |
| Database backup | Logical backups: use any supported command-line interface (CLI) or graphical user interface (GUI) tool. Physical backups: use the RDS console or API only. |
| Data restoration | Logical restore: use any supported CLI or GUI tool. Physical restore: use the RDS console or API only. |
| Storage engine | InnoDB is the only supported storage engine. We recommend that you use InnoDB for performance and security purposes. The MEMORY engine is not supported — tables created with the MEMORY engine are automatically converted to InnoDB. |
| Database replication | RDS MariaDB uses a dual-node cluster based on a primary/secondary replication architecture. The secondary instance is not directly accessible to your application. |
| Instance restart | Restart instances through the RDS console or API. |