Aurora Serverless v2 reader doesn't seem to scale independently

Question

What could be the problem of the reader instance not showing in Cloudwatch that it uses less capacity than the writer? (tried all the solutions from the AWS documentation)

Answer 1

According to the following documentation:

https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/aurora-serverless-v2-administration.html#aurora-serverless-v2-choosing-promotion-tier

You have to set the promotion tier of the reader ( or of all instances to > 2). Otherwise the reader will be always on the same tier as the writer as the reader should be prepared to become the Writer in case of failover.