Explain the EKS control plane versus worker node responsibilities.
AWS · Intermediate level
Answer
The EKS control plane includes managed API server and etcd; worker nodes run kubelet, pods, networking components, and container runtime. AWS manages control-plane infrastructure, while customer operations focus heavily on nodes and workloads.
Technical explanation
Pods Pending usually point to node, scheduling, quota, taint, or CNI issues rather than the control plane.
EKS is managed Kubernetes, not no-ops Kubernetes: IAM, networking, add-ons, node strategy, upgrades, RBAC, policies, and workload reliability remain customer responsibilities.
Workload identity, private networking, image security, ingress standards, autoscaling, and observability are foundational controls for production clusters.
Troubleshooting EKS requires separating control-plane, node, CNI, scheduler, ingress, and application failure domains.
Hands-on example
1. Create or use an EKS sandbox cluster with private subnets, managed add-ons, workload IAM, and a sample namespace.
2. Deploy a small container from ECR using Kubernetes manifests or Helm, with readiness/liveness probes and resource requests.
3. Add ingress/load balancing, pod IAM, logging, metrics, and network/security controls relevant to the question.
4. Test node replacement, pod rescheduling, image pulls, access control, and rollback.
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