- Kubeadm: Switched to using the new etcd endpoints introduced in 3.5.11 - /livez (for liveness probe) and /readyz (for readyness and startup probe). With this change it is no longer possible to deploy a custom etcd version older than 3.5.11 with kubeadm 1.31. If so, please upgrade etcd to a supported version. ([#124465](https://github.com/kubernetes/kubernetes/pull/124465),...

- Output a log as v4-level when probe is triggered and shift the periodic timer of ReadinessProbe after manual run. ([#119089](https://github.com/kubernetes/kubernetes/pull/119089), [@mochizuki875](https://github.com/mochizuki875)) [SIG Node]

* addon-resizer flapping behavior was removed. ([#46850](https://github.com/kubernetes/kubernetes/pull/46850), [@x13n](https://github.com/x13n))
* Change default `httpGet` probe `User-Agent` to `kube-probe/<version major.minor>` if none specified, overriding the default Go `User-Agent`. ([#47729](https://github.com/kubernetes/kubernetes/pull/47729), [@paultyng](https://github.com/paultyng))

## Changelog since v1.23.0-beta.0

## Changes by Kind

### API Change

- Add gRPC probe to Pod.Spec.Container.{Liveness,Readiness,Startup}Probe (#106463, @SergeyKanzhelev) [SIG API Machinery, Apps, CLI, Node and Testing]

- If someone had the `ProbeTerminationGracePeriod` alpha feature enabled in 1.21, they should update/delete any workloads/pods with probe `terminationGracePeriods` < 1 before upgrading ([#103245](https://github.com/kubernetes/kubernetes/pull/103245), [@wzshiming](https://github.com/wzshiming))

- Kubeadm: make sure the etcd static pod startup probe uses /health?serializable=false while the liveness probe uses /health?serializable=true&exclude=NOSPACE. The NOSPACE exclusion would allow administrators to address space issues one member at a time. ([#110744](https://github.com/kubernetes/kubernetes/pull/110744), [@neolit1...

  honor the specified `scheme` and `headers` fields. This enables setting custom
  headers and changing the scheme to `HTTPS`, consistent with container
  startup/readiness/liveness probe capabilities. Lifecycle handlers configured
  with `scheme: HTTPS` that encounter errors indicating the endpoint is actually
  using HTTP fall back to making the request over HTTP for compatibility with