Working with MariaDB read replicas
Following, you can find specific information about working with read replicas on Amazon RDS for MariaDB. For general information about read replicas and instructions for using them, see Working with DB instance read replicas.
Configuring read replicas with MariaDB
Before a MariaDB DB instance can serve as a replication source, make sure to turn on automatic backups on the source DB instance by setting the backup retention period to a value other than 0. This requirement also applies to a read replica that is the source DB instance for another read replica.
You can create up to 15 read replicas from one DB instance within the same Region. For replication to operate effectively, each read replica should have as the same amount of compute and storage resources as the source DB instance. If you scale the source DB instance, also scale the read replicas.
RDS for MariaDB supports cascading read replicas. To learn how to configure cascading read replicas, see Using cascading read replicas with RDS for MariaDB.
You can run multiple read replica create and delete actions at the same time that reference the same source DB instance. When you perform these actions, stay within the limit of 15 read replicas for each source instance.