Posted On: Jan 11, 2018
Starting today, Amazon RDS Read Replicas for MySQL and MariaDB now support Multi-AZ deployments. Combining Read Replicas with Multi-AZ enables you to build a resilient disaster recovery strategy and simplify your database engine upgrade process.
Amazon RDS Read Replicas enable you to create one or more read-only copies of your database instance within the same AWS Region or in a different AWS Region. Updates made to the source database are then asynchronously copied to your Read Replicas. In addition to providing scalability for read-heavy workloads, Read Replicas can be promoted to become a standalone database instance when needed.
Amazon RDS Multi-AZ deployments provide enhanced availability for database instances within a single AWS Region. With Multi-AZ, your data is synchronously replicated to a standby in a different Availability Zone (AZ). In the event of an infrastructure failure, Amazon RDS performs an automatic failover to the standby, minimizing disruption to your applications.
You can now use Read Replicas with Multi-AZ as part of a disaster recovery (DR) strategy for your production databases. A well-designed and tested DR plan is critical for maintaining business continuity after a disaster. A Read Replica in a different region than the source database can be used as a standby database and promoted to become the new production database in case of a regional disruption.
You can also combine Read Replicas with Multi-AZ for your database engine upgrade process. You can create a Read Replica of your production database instance and upgrade it to a new database engine version. When the upgrade is complete, you can stop applications, promote the Read Replica to a standalone database instance, and switch over your applications. Since the database instance is already a Multi-AZ deployment, no additional steps are needed.
For more information, see the Amazon RDS User Guide.