- `kubectl diff` now returns 1 only on diff finding changes, and >1 on kubectl errors. The "exit status code 1" message as also been muted. ([#87437](https://github.com/kubernetes/kubernetes/pull/87437), [@apelisse](https://github.com/apelisse)) [SIG CLI, and SIG Testing]

- CSI Migration: Fixes issue where all volumes with the same inline volume inner spec name were staged in the same path. Migrated inline volumes are now staged at a unique path per unique volume. ([#84754](https://github.com/kubernetes/kubernetes/pull/84754), [@davidz627](https://github.com/davidz627))

Federated Jobs that are automatically deployed to multiple clusters
are now supported. Cluster selection and weighting determine how Job
parallelism and completions are spread across clusters. Federated Job
status reflects the aggregate status across all underlying cluster
jobs.

#### [alpha] Federated Horizontal Pod Autoscaling (HPA)

Federated HPAs are similar to the traditional Kubernetes HPAs, except

### **Application Autoscaling**
#### Horizontal Pod Autoscaler
* [alpha] [HPA Status Conditions](https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale-walkthrough/#appendix-horizontal-pod-autoscaler-status-conditions).


### **Cluster Lifecycle**
#### kubeadm

  // +optional
  optional NamespaceSpec spec = 2;

  // Status describes the current status of a Namespace.
  // More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#spec-and-status
  // +optional
  optional NamespaceStatus status = 3;
}

// NamespaceCondition contains details about state of namespace.
message NamespaceCondition {

## Before Upgrading

* When Response is a `metav1.Status`, it is no longer copied into the audit.Event status. Only the "status", "reason" and "code" fields are set.  For example, when we run `kubectl get pods abc`, the API Server returns a status object:

- Kubelet now tries to stop containers in unknown state once before restart or remove. ([#73802](https://github.com/kubernetes/kubernetes/pull/73802), [@Random-Liu](https://github.com/Random-Liu))
- When pleg channel is full, events are now discarded and count is recorded ([#72709](https://github.com/kubernetes/kubernetes/pull/72709), [@changyaowei](https://github.com/changyaowei))

- Fixed a bug in the cronjob controller where already created jobs might be missing from the status. ([#120649](https://github.com/kubernetes/kubernetes/pull/120649), [@andrewsykim](https://github.com/andrewsykim))

- The calculation of pod UIDs for static pods has changed to ensure each static pod gets a unique value - this will cause all static pod containers to be recreated/restarted if an in-place kubelet upgrade from 1.20 to 1.21 is performed. Note that draining pods before upgrading the kubelet across minor versions is the supported upgrade path. ([#87461](https://github.com/kubernetes/kubernetes/pull/87461),...

### Bug or Regression

- Fix missing delete events on informer re-lists to ensure all delete events are correctly emitted and using the latest known object state, so that all event handlers and stores always reflect the actual apiserver state as best as possible ([#115900](https://github.com/kubernetes/kubernetes/pull/115900), [@odinuge](https://github.com/odinuge)) [SIG API Machinery]