What is EKS

Amazon Elastic Kubernetes Service (EKS) is AWS’s managed Kubernetes offering. By handling the control plane—API servers, etcd, schedulers, controllers—EKS lets you focus on deploying and operating your containerized workloads. Unlike a self-managed Kubernetes cluster, Amazon EKS splits responsibilities: AWS manages the control plane, while you maintain the data plane in your own AWS account.

Kubernetes Cluster Architecture

A standard Kubernetes cluster consists of two main layers:

1. Control Plane

   • etcd (the key/value store)
   • API Server
   • Scheduler
   • Controller Manager

2. Data Plane

   • Worker nodes (EC2 instances or AWS Fargate)
   • Pods and containers

For more on Kubernetes components, see the Kubernetes Documentation.

EKS Shared Responsibility Model

With Amazon EKS, AWS takes care of the highly available, secure control plane, while you manage your worker nodes and application workloads.

Control Plane ↔ Data Plane Communication

Under the hood, your worker nodes in one VPC communicate with the managed control plane in another VPC. AWS uses cross-account ENIs to bridge the two, similar to connecting two physical network switches with a cable:

• Your Network: Worker nodes plugged into your VPC.
• AWS’s Network: Control plane components housed in AWS’s VPC.

This link ensures secure, low-latency API calls and etcd reads/writes from your pods to the managed control plane.

Learn More

• Amazon EKS Documentation
• Kubernetes Cluster Architecture
• AWS VPC Networking
• AWS Fargate for EKS