When you change the configuration of an ApsaraDB RDS for MySQL instance or upgrade the major engine version of the RDS instance, an instance switchover occurs. As a result, the RDS instance becomes unavailable for a short period of time. You must perform the preceding operations during off-peak hours and make sure that your application is configured to automatically reconnect to the RDS instance.
Impacts
We recommend that you perform operations that involve instance switchovers during off-peak hours and make sure that your application is configured to automatically reconnect to your RDS instance.
Your RDS instance runs RDS Cluster Edition or RDS High-availability Edition. If a primary/secondary switchover is triggered, the RDS becomes unavailable for 30 to 120 seconds. For more information, see Switch workloads over between primary and secondary ApsaraDB RDS for MySQL instances.
NoteWhen you change the configuration of an RDS instance, if the resources on the host on which the RDS instance resides are insufficient, the system automatically creates a new RDS instance on a host that has sufficient resources and synchronizes the data of the original RDS instance to the new RDS instance. The synchronization does not affect your use of the original RDS instance. After the synchronization is complete, an instance switchover occurs, and your database system becomes unavailable for approximately 30 to 120 seconds.
Your RDS instance runs RDS Basic Edition. If an instance switchover is triggered, the RDS instance becomes unavailable for a long period of time. The period of time that is required varies based on the data volume of the RDS instance.