I'm trying to create an AWS Aurora read replica from an RDS MySQL Instance, but I'm getting the following error.
IAM Database Authentication is not supported for this configuration. (Service: AmazonRDS; Status Code: 400; Error Code: InvalidParameterCombination; Request ID: cabe107c-d4c9-4d97-9222-b659622a04b6; Proxy: null)
It turns out that my problem was that I was trying to create a db.t2.small instance, but IAM authentication is not supported for AWS Aurora on db.t2.small instances and is not supported for RDS MySQL for db.t2.small or db.m1.small instances. I changed the instance type to db.t2.medium and that resolved the problem.
I think (but I'm not sure) that IAM Authentication is required because I had Enhanced monitoring enabled, so I may have been able to fix the problem by disabling that, but I have not tested that.
