AWS AmazonRDS documentation change
Summary
Added new section 'Switchover when using Amazon RDS Proxy' detailing guardrail checks, traffic routing behavior, and API behavior during switchover when RDS Proxy is involved.
Security assessment
The changes document operational behavior during switchover with RDS Proxy, including connection handling and error messages. There is no evidence of addressing a security vulnerability; instead, it clarifies expected behavior during deployment transitions to prevent application errors and ensure smooth failover.
Diff
diff --git a/AmazonRDS/latest/AuroraUserGuide/blue-green-deployments-switching.md b/AmazonRDS/latest/AuroraUserGuide/blue-green-deployments-switching.md index 8d7667e89..9140cfeeb 100644 --- a//AmazonRDS/latest/AuroraUserGuide/blue-green-deployments-switching.md +++ b//AmazonRDS/latest/AuroraUserGuide/blue-green-deployments-switching.md @@ -5 +5 @@ -Switchover timeoutSwitchover guardrailsSwitchover actionsSwitchover best practicesVerifying CloudWatch metrics before switchoverMonitoring replica lag prior to switchoverSwitching over a blue/green deploymentAfter switchover +Switchover timeoutSwitchover guardrailsSwitchover actionsSwitchover when using Amazon RDS ProxySwitchover best practicesVerifying CloudWatch metrics before switchoverMonitoring replica lag prior to switchoverSwitching over a blue/green deploymentAfter switchover @@ -20,0 +21,2 @@ _Switching over_ a blue/green deployment is not the same as _promoting_ the gree + * Switchover when using Amazon RDS Proxy + @@ -102,0 +105,27 @@ If the switchover starts and then stops before finishing for any reason, then an +## Switchover when using Amazon RDS Proxy + +In addition to the above mentioned switchover actions, if the blue cluster is a target of an Amazon RDS Proxy, the following behavior applies during switchover: + + * Switchover Guardrails + + * Amazon RDS runs additional guardrail checks to validate that the proxy can successfully reach both blue and green environments and is ready for switchover. + + * Application Traffic Routing During Switchover + + * During switchover, the Blue database enters read-only mode before Green environment is promoted. Amazon RDS Proxy continues routing connections to the blue database during this transitional period. + + * Write operations on Aurora MySQL during this period may return read-only errors. For example, `1290 (HY000): The MySQL server is running with the --read-only option` so it cannot execute this statement. On Aurora PostgreSQL, read and write queries will return `AdminShutdown: terminating connection due to administrator command`. + + * Once the switchover is detected, the proxy routes traffic to the newly promoted green environment. + + * When the Green environment is promoted as the new writer, existing connections to the proxy are dropped. Applications must re-establish connections after the promotion is complete. + + * You can review CloudWatch logs for Amazon RDS Proxy to see when this transitional behavior occurred. + + * RDS Proxy API Behavior + + * Proxy APIs such as `describe-db-proxy-targets` reflect the updated targets only after the switchover is fully complete, even though traffic routing occurs earlier. + + + +