EKS East-West Traffic Optimization Guide
Written: 2026-02-09 | Updated: 2026-02-14 | Reading time: ~21 min
Overview
This guide covers optimizing inter-service communication (East-West traffic) in Amazon EKS from latency minimization and cost efficiency perspectives. It progressively addresses scenarios from single cluster to multi-AZ, multi-cluster, and multi-account environments.
When East-West hops increase from 1 to 2, p99 latency grows by milliseconds. Cross-AZ traffic incurs AWS bandwidth charges ($0.01/GB). This guide analyzes layer-by-layer options from Kubernetes-native features (Topology Aware Routing, InternalTrafficPolicy) to Cilium ClusterMesh, AWS VPC Lattice, and Istio service mesh, with quantitative latency, overhead, and cost comparisons.
Key Benefits
| Item | Improvement |
|---|---|
| Network Latency | Same-AZ routing via Topology Aware Routing, sub-ms p99 |
| Cost Savings | ~$100/month at 10TB/month by eliminating cross-AZ traffic |
| Operational Simplicity | ClusterIP-based inter-service optimization without LBs |
| DNS Performance | NodeLocal DNSCache: ms → sub-ms DNS lookup |
| Scalability | Consistent extension path to multi-cluster/account |
🔀 Kubernetes 服务类型对比
East-West 流量的服务类型选择指南
💡 选择指南: 默认：ClusterIP + Topology Aware Routing | StatefulSet：Headless | 需要 L7：Internal ALB（IP 模式）| L4 外部暴露：Internal NLB（IP 模式）
Implementation
- Topology Aware Routing —
service.kubernetes.io/topology-mode: Auto - InternalTrafficPolicy Local — Same-node-only traffic
- Pod Topology Spread Constraints — AZ-balanced distribution
- NodeLocal DNSCache — Local DNS caching per node
- Internal LB IP Mode — Direct Pod IP targeting
- Istio Service Mesh (optional) — mTLS, locality-aware routing
Multi-Cluster Connection Strategies
- Cilium ClusterMesh: Lowest latency, Pod-to-Pod direct, eBPF-based
- AWS VPC Lattice: Managed proxy, IAM auth, multi-account
- Istio Multi-cluster: Full mesh features across clusters, mTLS
- Route53 + ExternalDNS: Simplest, DNS-based
⚡ 各选项延迟与成本对比
East-West 流量路径的性能·成本定量对比
💰 10 TB/月 East-West 流量成本模拟
同一区域 3-AZ EKS 集群，总计 10 TB（10,240 GB）服务间流量基准
🎯 按场景推荐矩阵
根据服务特性、安全需求和运维复杂度的推荐方案