S3 egress and inter-AZ traffic. The way they advertise multi-AZ should honestly be illegal, or at least include warnings about charges.
Like when you set up an RDS instance, the “prod” template defaults to multi-AZ (a good idea tbf), but completely elides the fact that if your app is in a different AZ, you’re going to start racking up $0.02/GB.
Same with NLBs and cross-AZ routing. Sure, it can be helpful, but yeesh.
Or EKS, since Topology Aware Routing is in no way a default.
Like when you set up an RDS instance, the “prod” template defaults to multi-AZ (a good idea tbf), but completely elides the fact that if your app is in a different AZ, you’re going to start racking up $0.02/GB.
Same with NLBs and cross-AZ routing. Sure, it can be helpful, but yeesh.
Or EKS, since Topology Aware Routing is in no way a default.