Kubernetes Topology Aware Routing
EKS’s default service routing spreads traffic across a cluster’s pods randomly, or round-robin. That means requests frequently land on a pod in a different availability zone (AZ), and since AWS VPC charges for cross-AZ data transfer, that traffic pattern translates directly into higher cost and added latency. Topology Aware Routing (TAR), introduced in Kubernetes 1.24, targets exactly this problem: when pods talk to each other, it adjusts network policy to prefer a pod in the same AZ whenever one is available. ...