America/Mexico_City America/Miquelon America/Moncton America/Monterrey America/Montevideo America/Montreal America/Montserrat America/Nassau America/New_York America/Nipigon America/Nome America/Noronha America/North_Dakota/Beulah America/North_Dakota/Center America/North_Dakota/New_Salem America/Nuuk America/Ojinaga America/Panama America/Pangnirtung America/Paramaribo America/Phoenix America/Port-au-Prince America/Port_of_Spain America/Porto_Acre America/Porto_Velho America/Puerto_Rico America/Punta_Arenas...

<h3 id="Identifiers">Identifiers</h3>

<p>
Identifiers name program entities such as variables and types.
An identifier is a sequence of one or more letters and digits.
The first character in an identifier must be a letter.
</p>
<pre class="ebnf">
identifier = letter { letter | unicode_digit } .
</pre>
<pre>
a
_x9
ThisVariableIsExported
αβ
</pre>

<p>

* Clean up the kube-proxy container image by removing unnecessary packages and files. ([#42090](https://github.com/kubernetes/kubernetes/pull/42090), [@timstclair](https://github.com/timstclair))
* Better compat with very old iptables (e.g. CentOS 6) ([#37594](https://github.com/kubernetes/kubernetes/pull/37594), [@thockin](https://github.com/thockin))

### Scheduler

* hyperkube

  * The hyperkube image has been slimmed down and no longer includes addon manifests and other various scripts. These were introduced for the now removed docker-multinode setup system. ([#44555](https://github.com/kubernetes/kubernetes/pull/44555), [@luxas](https://github.com/luxas))

#### Lifecycle

- Support for deprecated old kubeadm v1alpha3 config has been totally removed. ([#75179](https://github.com/kubernetes/kubernetes/pull/75179), [@rosti](https://github.com/rosti))
- kube-up.sh no longer supports "centos" and "local" providers. ([#76711](https://github.com/kubernetes/kubernetes/pull/76711), [@dims](https://github.com/dims))

#### Network

- Namespace editors and admins can now create leases.coordination.k8s.io and should use this type for leaderelection instead of configmaps. ([#111515](https://github.com/kubernetes/kubernetes/pull/111515), [@deads2k](https://github.com/deads2k)) [SIG API Machinery and Auth]

  // 1) run as Privileged
  // 2) has CAP_SYS_ADMIN
  // Note that this field cannot be set when spec.os.name is windows.
  // +optional
  optional bool allowPrivilegeEscalation = 7;

  // procMount denotes the type of proc mount to use for the containers.
  // The default is DefaultProcMount which uses the container runtime defaults for
  // readonly paths and masked paths.

  Plugins **have to** implement a QueueingHint for Pod/Update event if the rejection from them could be resolved by updating unscheduled Pods themselves.
  Example: suppose you develop a custom plugin that denies Pods that have a `schedulable=false` label. 

- The namespace editors and admins can now create leases.coordination.k8s.io and should use this type for leaderelection instead of configmaps. ([#111472](https://github.com/kubernetes/kubernetes/pull/111472), [@deads2k](https://github.com/deads2k))

A security issue was discovered in kube-apiserver that could allow node
updates to bypass a Validating Admission Webhook. You are only affected
by this vulnerability if you run a Validating Admission Webhook for Nodes
that denies admission based at least partially on the old state of the
Node object.

**Note**: This only impacts validating admission plugins that rely on old
values in certain fields, and does not impact calls from kubelets that go