A primary/secondary switchover for an ApsaraDB RDS for PostgreSQL instance is triggered by planned maintenance or unplanned failures. Identifying the cause helps you determine whether the switchover was expected and whether any follow-up action is needed.
Planned switchovers
Planned switchovers occur when Alibaba Cloud or you initiate a controlled switch to the secondary instance.
Vulnerability fixes (platform-initiated)
When Alibaba Cloud detects vulnerabilities that could prevent the instance from running normally, it applies fixes to the secondary instance first, then performs a switchover during the maintenance window to shift your workloads to the patched instance.
For high-risk vulnerabilities, the fix and switchover happen at the earliest opportunity.
Manual switchover (user-initiated)
You or an authorized Alibaba Cloud technical expert manually trigger a primary/secondary switchover.
Unplanned switchovers
Unplanned switchovers are triggered automatically when Alibaba Cloud detects failures that may cause the instance to fail to run as normal. The system switches your workloads to the secondary instance to minimize impact.
After a switchover
Once a switchover is complete, the instance status changes to Running. No further action is required — the instance resumes normal operation automatically.
To view switchover history, go to the Service Availability page of the instance in the ApsaraDB RDS console and check the Primary/Secondary Switching Logs section.
