Amazon EKS Kubernetes versions

• 1.21.2

• 1.20.7

• 1.19.8

• 1.18.16

• 1.17.17

Important

• Dual-stack networking support (IPv4 and IPv6 addresses) on pods, services, and nodes has reached beta status. However, Amazon EKS and the Amazon VPC CNI don't currently support dual stack networking.

• The Amazon EKS Optimized Amazon Linux 2 AMI now contains a bootstrap flag to enable the containerd runtime as a Docker alternative. This flag allows preparation for the removal of Docker as a supported runtime in the next Kubernetes release. For more information, see Enable the containerd runtime bootstrap flag. This can be tracked through the container roadmap on Github.

• Managed node groups support for Cluster Autoscaler priority expander.

  Newly created managed node groups on Amazon EKS v1.21 clusters use the following format for the underlying Auto Scaling group name:

  eks-<managed-node-group-name>-<uuid>

  This enables using the priority expander feature of Cluster Autoscaler to scale node groups based on user defined priorities. A common use case is to prefer scaling spot node groups over on-demand groups. This behavior change solves the containers roadmap issue #1304.

• CronJobs (previously ScheduledJobs) have now graduated to stable status. With this change, users perform regularly scheduled actions such as backups and report generation.

• Immutable Secrets and ConfigMaps have now graduated to stable status. A new, immutable field was added to these objects to reject changes. This rejection protects the cluster from updates that can unintentionally break the applications. Because these resources are immutable, kubelet doesn't watch or poll for changes. This reduces kube-apiserver load and improving scalability and performance.

• Graceful Node Shutdown has now graduated to beta status. With this update, the kubelet is aware of node shutdown and can gracefully terminate that node's pods. Before this update, when a node shut down, its pods didn't follow the expected termination lifecycle. This caused workload problems. Now, the kubelet can detect imminent system shutdown through systemd, and inform running pods so they terminate gracefully.

• Pods with multiple containers can now use the kubectl.kubernetes.io/default-container annotation to have a container preselected for kubectl commands.

• PodSecurityPolicy is being phased out. PodSecurityPolicy will still be functional for several more releases according to Kubernetes deprecation guidelines. For more information, see PodSecurityPolicy Deprecation: Past, Present, and Future and the AWS blog.

Important

• 1.20 brings new default roles and users. You can find more information in Default EKS Kubernetes roles and users.

• API Priority and Fairness has reached beta status and is enabled by default. This allows kube-apiserver to categorize incoming requests by priority levels.

• RuntimeClass has reached stable status. The RuntimeClass resource provides a mechanism for supporting multiple runtimes in a cluster and surfaces information about that container runtime to the control plane.

• Process ID Limits has now graduated to general availability.

• kubectl debug has reached beta status. kubectl debug provides support for common debugging workflows directly from kubectl.

• The Docker container runtime has been phased out. The Kubernetes community has written a blog post about this in detail with a dedicated FAQ page. Docker-produced images can continue to be used and will work as they always have. You can safely ignore the dockershim deprecation warning message printed in kubelet startup logs. EKS will eventually move to containerd as the runtime for the EKS optimized Amazon Linux 2 AMI. You can follow the containers roadmap issue for more details.

• Pod Hostname as FQDN has graduated to beta status. This feature allows setting a pod’s hostname to its Fully Qualified Domain Name (FQDN), giving the ability to set the hostname field of the kernel to the FQDN of a Pod.

• The client-go credential plugins can now be passed in the current cluster information via the KUBERNETES_EXEC_INFO environment variable. This enhancement allows Go clients to authenticate using external credential providers, such as a key management system (KMS).

Important

• Starting with 1.19, Amazon EKS no longer adds the kubernetes.io/cluster/<cluster-name> tag to subnets passed in when clusters are created. This subnet tag is only required if you want to influence where the Kubernetes service controller or AWS Load Balancer Controller places Elastic Load Balancers. For more information about the requirements of subnets passed to Amazon EKS during cluster creation, see updates to Cluster VPC considerations.

  • Subnet tags aren't modified on existing clusters updated to 1.19.

  • The AWS Load Balancer Controller version v2.1.1 and earlier required the <cluster-name> subnet tag. In version v2.1.2 and later, you can specify the tag to refine subnet discovery, but it's not required. For more information about the AWS Load Balancer Controller, see AWS Load Balancer Controller. For more information about subnet tagging when using a load balancer, see Application load balancing on Amazon EKS and Network load balancing on Amazon EKS.

• You're no longer required to provide a security context for non-root containers that need to access the web identity token file for use with IAM roles for service accounts. For more information, see IAM roles for service accounts andproposal for file permission handling in projected service account volume on GitHub.

• The pod identity webhook has been updated to address the missing startup probes GitHub issue. The webhook also now supports an annotation to control token expiration. For more information, see the GitHub pull request.

• CoreDNS version 1.8.0 is the recommended version for Amazon EKS 1.19 clusters. This version is installed by default in new Amazon EKS 1.19 clusters. For more information, see Managing the CoreDNS add-on.

• Amazon EKS optimized Amazon Linux 2 AMIs include the Linux kernel version 5.4 for Kubernetes version 1.19. For more information, see Amazon EKS optimized Amazon Linux AMI.

• The CertificateSigningRequest API has been promoted to stable certificates.k8s.io/v1 with the following changes:

  • spec.signerName is now required. You can't create requests for kubernetes.io/legacy-unknown with the certificates.k8s.io/v1 API.

  • You can continue to create CSRs with the kubernetes.io/legacy-unknown signer name with the certificates.k8s.io/v1beta1 API.

  • You can continue to request that a CSR to is signed for a non-node server cert, webhooks (for example, with the certificates.k8s.io/v1beta1 API). These CSRs aren't auto-approved.

  • To approve certificates, a privileged user requires kubectl 1.18.8 or later.

  For more information about the certificate v1 API, see Certificate Signing Requests in the Kubernetes documentation.

• The ExtendedResourceToleration admission controller is enabled. This admission controller automatically adds tolerations for taints to pods requesting extended resources, such as GPUs, so you don't have to manually add the tolerations. For more information, see ExtendedResourceToleration in the Kubernetes documentation.

• Elastic Load Balancers (CLB and NLB) provisioned by the in-tree Kubernetes service controller support filtering the nodes included as instance targets. This can help prevent reaching target group limits in large clusters. For more information, see the related GitHub issue and the service.beta.kubernetes.io/aws-load-balancer-target-node-labels annotation under Other ELB annotations in the Kubernetes documentation.

• Pod Topology Spread has reached stable status. You can use topology spread constraints to control how pods are spread across your cluster among failure-domains such as regions, zones, nodes, and other user-defined topology domains. This can help to achieve high availability, as well as efficient resource utilization. For more information, see Pod Topology Spread Constraints in the Kubernetes documentation.

• The Ingress API has reached general availability. For more information, see Ingress in the Kubernetes documentation.

• EndpointSlices are enabled by default. EndpointSlices are a new API that provides a more scalable and extensible alternative to the Endpoints API for tracking IP addresses, ports, readiness, and topology information for Pods backing a Service. For more information, see Scaling Kubernetes Networking With EndpointSlices in the Kubernetes blog.

• Secret and ConfigMap volumes can now be marked as immutable. This significantly reduces load on the API server if there are many Secret and ConfigMap volumes in the cluster. For more information, see ConfigMap and Secret in the Kubernetes documentation.

• Topology Manager has reached beta status. This feature allows the CPU and Device Manager to coordinate resource allocation decisions, optimizing for low latency with machine learning and analytics workloads. For more information, see Control Topology Management Policies on a node in the Kubernetes documentation.

• Server-side Apply is updated with a new beta version. This feature tracks and manages changes to fields of all new Kubernetes objects, allowing you to know what changed your resources and when. For more information, see What is Server-side Apply? in the Kubernetes documentation.

• A new pathType field and a new IngressClass resource has been added to the Ingress specification. These features make it simpler to customize Ingress configuration, and are supported by the AWS Load Balancer Controller (formerly called the ALB Ingress Controller). For more information, see Improvements to the Ingress API in Kubernetes 1.18 in the Kubernetes documentation.

• Configurable horizontal pod autoscaling behavior. For more information, see Support for configurable scaling behavior in the Kubernetes documentation.

• In 1.18 clusters, you no longer need to include the AWS_DEFAULT_REGION=<region-code> environment variable to pods when using IAM roles for service accounts in China Regions, whether you use the mutating web hook or configure the environment variables manually. You still need to include the variable for all pods in earlier versions.

• New clusters contain updated default values in externalTrafficPolicy. HealthyThresholdCount and UnhealthyThresholdCount are 2 each, and HealthCheckIntervalSeconds is reduced to 10 seconds. Clusters created in older versions and upgraded retain the old values.

• Cloud Provider Labels have reached general availability. If you're using the beta labels in your pod specs for features such as node affinity, or in any custom controllers, then we recommend that you start migrating them to the new GA labels. For information about the new labels, see the following Kubernetes documentation:

  • node.kubernetes.io/instance-type

  • topology.kubernetes.io/region

  • topology.kubernetes.io/zone

• The ResourceQuotaScopeSelectors feature has graduated to generally available. You can use this feature to limit the number of resources a quota supports to only those that pertain to the scope.

• The TaintNodesByCondition feature has graduated to generally available. This feature allows you to taint nodes that have conditions such as high disk or memory pressure.

• The CSI Topology feature has graduated to generally available, and is fully supported by the EBS CSI driver. You can use topology to restrict the Availability Zone where a volume is provisioned.

• Finalizer protection for services of type LoadBalancer has graduated to generally available. This feature ensures that a service resource isn't fully deleted until the correlating load balancer is also deleted.

• Custom resources now support default values. You specify values in an OpenAPI v3 validation schema.

• The Windows containers RunAsUsername feature is now in beta. You can use it to run Windows applications in a container as a different user name than the default.

• Volume expansion in the CSI specification has moved to beta. This allows for any CSI spec volume plugin to be resizeable. For more information, see Volume Expansion in the Kubernetes CSI documentation. The latest version of the EBS CSI driver supports volume expansion when running on an Amazon EKS 1.16 cluster.

• Windows GMSA support has graduated from alpha to beta, and is now supported by Amazon EKS. For more information, see Configure GMSA for Windows Pods and containers in the Kubernetes documentation.

• A new annotation: service.beta.kubernetes.io/aws-load-balancer-eip-allocations is available on service type LoadBalancer to assign an elastic IP address to Network Load Balancers. For more information, see the Support EIP Allocations with AWS NLB GitHub issue.

• Finalizer protection for service load balancers is now in beta and enabled by default. Service load balancer finalizer protection ensures that any load balancer resources that are allocated for a Kubernetes Service object, such as network load balancers, are be destroyed or released when the service is deleted. For more information, see Garbage Collecting Load Balancers in the Kubernetes documentation.

• The Kubernetes custom resource definitions and admission webhooks extensibility mechanisms have both reached general availability. For more information, see Custom Resources and Dynamic Admission Control in the Kubernetes documentation.

• The server-side apply feature has reached beta status and is enabled by default. For more information, see Server Side Apply in the Kubernetes documentation.

• The CustomResourceDefaulting feature is promoted to beta and enabled by default. Defaults might be specified in structural schemas through the apiextensions.k8s.io/v1 API. For more information, see Specifying a structural schema in the Kubernetes documentation.