- kubeadm: JoinConfiguration now houses the discovery options in a nested Discovery structure, which in turn has a couple of other nested structures to house more specific options (BootstrapTokenDiscovery and FileDiscovery) ([#67763](https://github.com/kubernetes/kubernetes/pull/67763), [@rosti](https://github.com/rosti))

rate limit is switched to per-client. A set of new rate limit configure options are introduced, including routeRateLimit, SubnetsRateLimit, InterfaceRateLimit, RouteTableRateLimit, LoadBalancerRateLimit, PublicIPAddressRateLimit, SecurityGroupRateLimit, VirtualMachineRateLimit, StorageAccountRateLimit, DiskRateLimit, SnapshotRateLimit, VirtualMachineScaleSetRateLimit and VirtualMachineSizeRateLimit. The original rate limit options would be default values for those new client's rate limiter. ([#8651...

*   You can now add "options" to the host's /etc/resolv.conf (or --resolv-conf), and they will be copied into pod's resolv.conf when dnsPolicy is Default. Being able to customize options is important because it is common to leverage options to fine-tune the behavior of DNS client. ([#54773](https://github.com/kubernetes/kubernetes/pull/54773),[ @phsiao](https://github.com/phsiao))...

#### Storage

* [stable] Mount options

  * The ability to specify mount options for volumes is moved from beta to stable.

  * A new `MountOptions` field in the `PersistentVolume` spec is available to specify mount options. This field replaces an annotation.

  * A new `MountOptions` field in the `StorageClass` spec allows configuration of mount options for dynamically provisioned volumes.

  and it can be enabled by setting the option `--feature-gates=AllowUnsafeMalformedObjectDeletion=true`.
  It comes with an API change, a new delete option `ignoreStoreReadErrorWithClusterBreakingPotential` has
  been introduced, it is not set by default, this maintains backward compatibility.
  In order to perform an unsafe deletion of a corrupt resource, the user must enable the option for the delete

* etcd client add dial timeout. ([#61459](https://github.com/kubernetes/kubernetes/pull/61459), [@hzxuzhonghu](https://github.com/hzxuzhonghu))
* nil admission options are now consistent with other nil options. ([#63993](https://github.com/kubernetes/kubernetes/pull/63993), [@tamalsaha](https://github.com/tamalsaha))

- Added options for configuring `nf_conntrack_udp_timeout`, and `nf_conntrack_udp_timeout_stream` variables of netfilter conntrack subsystem. ([#120808](https://github.com/kubernetes/kubernetes/pull/120808), [@aroradaman](https://github.com/aroradaman))

- Added new option to the InterPodAffinity scheduler plugin to ignore existing pods` preferred inter-pod affinities if the incoming pod has no preferred inter-pod affinities. This option can be used as an optimization for higher scheduling throughput (at the cost of an occasional pod being scheduled non-optimally/violating existing pods' preferred inter-pod affinities). To enable this scheduler option, set the InterPodAffinity scheduler plugin arg "ignor...

- Pod eviction now honors graceful deletion by default if no delete options are provided in the eviction request. ([#72730](https://github.com/kubernetes/kubernetes/pull/72730), [@liggitt](https://github.com/liggitt))

### Auth

    * `kubectl create configmap` has a new option `--from-env-file` that populates a configmap from file which follows a key=val format for each line. ([#38882](https://github.com/kubernetes/kubernetes/pull/38882), [@fraenkel](https://github.com/fraenkel))

    * `kubectl create secret` has a new option `--from-env-file` that populates a secret from file which follows a key=val format for each line.