EKS clusters should run on a supported Kubernetes version

How to fix it

• Can break clients: Workloads that call a Kubernetes API the target release removed stop working, so check the cluster's Upgrade insights tab before each step.
• Can't be undone: You can roll back only one version and only within 7 days of the upgrade; after that, going back means building a new cluster.
• Affects another check: Managed node groups are not upgraded with the control plane: each must be moved to the new version before the next step, and any still below the floor keeps failing EKS.9.

In the console

EKS → Clusters → the cluster → Upgrade now

Kubernetes version

The next minor version, repeated one release at a time until the cluster is on a recent release in standard support

With the AWS CLI

aws eks update-cluster-version --name <cluster-name> --kubernetes-version <version> --region <region>

With Terraform

resource "aws_eks_cluster" "this" {
  name     = "example"
  role_arn = aws_iam_role.eks_cluster.arn
  version  = var.kubernetes_version

  vpc_config {
    subnet_ids = var.private_subnet_ids
  }
}