What is the difference between managed (EKS) and unmanaged Kubernetes? What is on the AWS side and what is on the DevOps engineer's side?

Managed Kubernetes (e.g., Amazon EKS) is a service where AWS takes care of managing the cluster control plane: API server, etcd, scheduler, and controllers. AWS ensures high availability, updates, scaling, and security of the control plane.

Unmanaged Kubernetes is when a DevOps engineer independently deploys and maintains the entire cluster, including the control plane and worker nodes.

On the AWS side in EKS:

• Management of the control plane (API server, etcd, controllers)
• Ensuring fault tolerance and updates of the control plane
• Integration with AWS services (IAM, VPC, CloudWatch)

On the DevOps engineer's side:

• Management of worker nodes (EC2 instances or Fargate)
• Network, security, and access role configuration
• Deployment of applications and resource management within the cluster
• Monitoring and logging

Thus, EKS relieves DevOps from the task of maintaining the control plane, allowing focus on infrastructure and applications.