RDS Proxy RO Endpoint fallback to writer instance?

Question

Hello, I would like to know if its possible to configure a RDS Proxy RO Endpoint to fallback to the writer instance if there are no read replicas in the cluster?

My software is configured to use both RDS Proxy Endpoints (writer and read-only) but if I delete the RDS read replica instance (because there is not enough load to justify the cost) I am getting connections errors to the Proxy RO endpoint.

Thanks for help, I hope this is clear.

Raghu_C · Answer

When you create a new endpoint  that is read-only, RDS Proxy requires that the Aurora cluster has one or more reader DB instances. In some cases, you might change the target of the proxy to an Aurora cluster containing only a single writer or a multi-writer Aurora cluster. If you do, any requests to the reader endpoint fail with an error. Requests also fail if the target of the proxy is an RDS instance instead of an Aurora cluster.

If an Aurora cluster has reader instances but those instances aren't available, RDS Proxy waits to send the request instead of returning an error immediately. If no reader instance becomes available within the connection borrow timeout period, the request fails with an error.

[+] https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/rds-proxy-endpoints.html#rds-proxy-endpoints-reader

RDS Proxy RO Endpoint fallback to writer instance?

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