I'm looking to spin up a Kubernetes cluster on AWS that will access resources (e.g. RDS, ElastiCache) that are not on a VPC.

I was able to set up access to RDS by enabling ClassicLink on the kubernetes-vpc VPC, but this required commenting out the creation of one of Kubernetes' route tables (which conflicted with ClassicLink's route tables), which breaks some of Kubernetes networking. ElastiCache is more difficult, as it looks like its access is only grantable via classic EC2 security groups, which can't be associated with a VPC EC2 instance, AFAICT.

Is there a way to do this? I'd prefer not to use a NAT instance to provide access to ElastiCache.