Comment by toredash

I would LOVE to pitch something else I'm working on that is solving this problem in EKS, cross zone data transfer.

It's a plugin that enables traffic re-direction for any service that is using an IP in any given VPC. If you have say multiple RDS Reader instances, it will first attempt to use local AZ instances first, but the other instances are available if local instances are non-functional. So you do not loose HA or failover features.

The plugin does not require any reconfiguration on your apps. It works similar to Topology Aware Routing (https://kubernetes.io/docs/concepts/services-networking/topo...) in Kubernetes, but it works for services outside of Kubernetes. The plugin even works for non-Kubernetes setup as well.

This AZP solution is fine for services that is have one IP or primary instance, like RDS Writer instance. It does not work for anything that is "stateless" and multi-AZ, like RDS Read-only instances or ALBs.