ApsaraDB RDS for SQL Server - Optimizes the Automatic Primary/secondary Switchover and Automatic Repair Mechanism for RDS Instances That Run SQL Server EE on RDS Cluster Edition
Jun 01 2023ApsaraDB RDS for SQL Server
If your RDS instance runs RDS Cluster Edition and the primary RDS instance becomes faulty due to network failures or other reasons, the system triggers a primary/secondary switchover to promote the secondary RDS instance as the new primary RDS instance. This ensures the availability of your database system. During the switchover, the read weights of the primary and secondary RDS instances are also automatically exchanged. This allows the RDS instance that has only read permissions to process both read and write requests. In addition, the original primary RDS instance is automatically repaired. During the repair process, the original primary RDS instance enters the Maintaining Instance state. In this case, you cannot perform operations such as upgrading the major engine version, update the minor engine version, or modify read weight configurations. After the original primary RDS instance is repaired, the system triggers another primary/secondary switchover for the original primary RDS instance to enter the Running state and provide services as normal. During the switchover, the read weights are also automatically exchanged.