- **Federation**
  - [alpha] Support for ConfigMaps in federation. ([docs](http://kubernetes.io/docs/user-guide/federation/configmap/)) ([kubernetes/features#105](https://github.com/kubernetes/enhancements/issues/105))

### Immutable Secrets and ConfigMaps

Immutable Secrets and ConfigMaps graduates to GA. This feature allows users to specify that the contents of a particular Secret or ConfigMap is immutable for its object lifetime. For such instances, Kubelet will not watch/poll for changes and therefore reducing apiserver load.

### Structured Logging in Kubelet

  - [Known Issues](#known-issues)
    - [LocalStorageCapacityIsolationFSQuotaMonitoring ConfigMap rendering failure](#localstoragecapacityisolationfsquotamonitoring-configmap-rendering-failure)
  - [Urgent Upgrade Notes](#urgent-upgrade-notes)
    - [(No, really, you MUST read this before you upgrade)](#no-really-you-must-read-this-before-you-upgrade)

* Release the kubelet client certificate rotation as beta. ([#51045](https://github.com/kubernetes/kubernetes/pull/51045), [@jcbsmpsn](https://github.com/jcbsmpsn))
* Adds --append-hash flag to kubectl create configmap/secret, which will append a short hash of the configmap/secret contents to the name during creation. ([#49961](https://github.com/kubernetes/kubernetes/pull/49961), [@mtaufen](https://github.com/mtaufen))

  
  v1beta3 is now marked as deprecated but will continue to be supported until version 1.34 or later.
  The storage configuration in the kube-system/kubeadm-config ConfigMap is now a v1beta4 ClusterConfiguration. ([#125029](https://github.com/kubernetes/kubernetes/pull/125029), [@neolit123](https://github.com/neolit123))

* kubelet: resolved hang/timeout issues when running large numbers of pods with unique configmap/secret references ([#74755](https://github.com/kubernetes/kubernetes/pull/74755), [@liggitt](https://github.com/liggitt))

enabled kubeadm will start using a new naming format for the ConfigMap where it stores the KubeletConfiguration structure. The old format included the Kubernetes version - "kube-system/kubelet-config-1.22", while the new format does not - "kube-system/kubelet-config". A similar formatting change is done for the related RBAC rules. The old format is now DEPRECATED and will be removed after the feature graduates to GA. When writing the ConfigMap kubeadm (init, upgrade apply) will respect the value of ...

- Kubeadm: fix a regression where the KubeletConfiguration is not properly downloaded during "kubeadm upgrade" commands from the kube-system/kubelet-config ConfigMap, resulting in the local '/var/lib/kubelet/config.yaml' file being written as a defaulted config. ([#124497](https://github.com/kubernetes/kubernetes/pull/124497), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]

* kubelet: resolved hang/timeout issues when running large numbers of pods with unique configmap/secret references by reverting to 1.11 configmap/secret lookup behavior ([#74755](https://github.com/kubernetes/kubernetes/pull/74755), [@liggitt](https://github.com/liggitt))

- The beta `RootCAConfigMap` feature gate is enabled by default and causes kube-controller-manager to publish a "kube-root-ca.crt" ConfigMap to every namespace. This ConfigMap contains a CA bundle used for verifying connections to the kube-apiserver. ([#96197](https://github.com/kubernetes/kubernetes/pull/96197), [@zshihang](https://github.com/zshihang)) [SIG API Machinery, Apps, Auth and Testing]