- Kubeadm: Added the `HTTPEndpoints` field to `ClusterConfiguration.Etcd.ExternalEtcd` to configure HTTP endpoints for etcd communication in v1beta4. This separates HTTP traffic (e.g., `/metrics`, `/health`) from gRPC traffic, improving access control. Mirrors etcd’s `--listen-client-http-urls` behavior; if...

### Bug or Regression

- Kubeadm: fixed bug where v1beta3's ClusterConfiguration.APIServer.TimeoutForControlPlane is not respected in newer versions of kubeadm where v1beta4 is the default. ([#133754](https://github.com/kubernetes/kubernetes/pull/133754), [@HirazawaUi](https://github.com/HirazawaUi)) [SIG Cluster Lifecycle]...

- kubeadm ClusterConfiguration now supports featureGates: IPv6DualStack: true ([#80145](https://github.com/kubernetes/kubernetes/pull/80145), [@Arvinderpal](https://github.com/Arvinderpal))

### Bug or Regression

- Remove `tolerate-unready-endpoints` annotation...

- Kubeadm: avoided uploading a defaulted flag value "--authorization-mode=Node,RBAC" for the kube-apiserver in the ClusterConfiguration stored in the "kube-system/kubeadm-config" ConfigMap. "Node,RBAC" are already the kubeadm defaults for this flag, so this action is redundant. ([#123555](https://github.com/kubernetes/kubernetes/pull/123555), [@neolit123](https://github.com/neolit123))...

- Kubeadm: external etcd endpoints passed in the `ClusterConfiguration` that have Unicode characters are no longer IDNA encoded (converted to Punycode). They are now just URL encoded as per Go's implementation of RFC-3986, have duplicate "/" removed from the URL paths, and passed like that directly to the `kube-apiserver`...

- Kubeadm: during "upgrade apply/diff/node", in case the `ClusterConfiguration.imageRepository` stored in the "kubeadm-config" `ConfigMap` contains the legacy "k8s.gcr.io" repository, modify it to the new default "registry.k8s.io". Reflect the change in the in-cluster `ConfigMap` only during "upgrade apply". ([#11034...

- Kubeadm: fixed bug where v1beta3's ClusterConfiguration.APIServer.TimeoutForControlPlane is not respected in newer versions of kubeadm where v1beta4 is the default. ([#133753](https://github.com/kubernetes/kubernetes/pull/133753), [@HirazawaUi](https://github.com/HirazawaUi)) [SIG Cluster Lifecycle]...