ApsaraDB RDS provides various solutions for disaster recovery.
Multi-zone ApsaraDB RDS instances
Alibaba Cloud provides cloud computing services for regions around the world. Each region consists of multiple zones. Zones in the same region have low network latency, and a fault in one zone does not affect the services in other zones.
If you select the single-zone deployment method, your database system is deployed on two physical servers that reside in the same zone. All racks, air conditioners, circuits, and networking in the zone are redundant to ensure high availability. ApsaraDB RDS provides service availability that goes beyond the limits of physical servers by using the asynchronous or semi synchronous replication mode and an efficient primary/secondary failover mechanism.
To provide higher availability than a single zone, ApsaraDB RDS supports database system deployment in different zones in the same region. If you select the multi-zone deployment method, your database system is deployed on two physical servers that reside in different zones. If one zone fails, your database service can be switched over to the other zone within a short period of time. The switchover process is transparent and does not require changes to the application code.
- When a primary/secondary switchover occurs, the connection to the RDS instance is closed and the application needs to reconnect to the RDS instance.
- For more information about how to migrate an RDS instance across zones, see Migrate an ApsaraDB RDS for MySQL instance across zones in the same region.
Disaster recovery ApsaraDB RDS instances
Multi-zone RDS instances provide disaster recovery across different zones within the same region. To improve availability, ApsaraDB RDS also supports cross-region disaster recovery. For example, you can asynchronously replicate the data of Instance A in the China (Hangzhou) region to Instance B in the Chine (Shanghai) region by using Data Transmission Service (DTS). Instance B is an independent RDS instance that has its own endpoints, accounts, and permissions.
After Instance B is created, if a fault occurs in the China (Hangzhou) region, you can perform a disaster recovery switchover between Instance A and Instance B. After the switchover is complete, you must modify the connection configuration in your application for the application to connect to Instance B.
- Before you perform a disaster recovery switchover, you must stop the data replication from Instance A to Instance B to prevent data errors.
- For more information about how to create a disaster recovery instance, see Create a disaster recovery ApsaraDB RDS for MySQL instance.