passed a file which contains RBAC roles, rolebindings, clusterroles, or
  clusterrolebindings, this command computes covers and adds the missing rules.
  The logic required to properly apply RBAC permissions is more complicated
  than a JSON merge because you have to compute logical covers operations between
  rule sets. This means that we cannot use `kubectl apply` to update RBAC roles

- `Kubelet` no longer creates certain legacy iptables rules by default.
  It is possible that this will cause problems with some third-party components
  that improperly depended on those rules. If this affects you, you can run

- The kube-proxy `sync_proxy_rules_iptables_total` metric has now reverted back
  to its pre-1.27 behavior of tracking the total number of iptables rules that
  kube-proxy is responsible for, rather than only counting the number of rules
  that it re-synced on the last sync. The new `sync_proxy_rules_iptables_last`

`master` in labels and taints. For new clusters, the label `node-role.kubernetes.io/master` will no longer be added to control plane nodes, only the label `node-role.kubernetes.io/control-plane` will be added. For clusters that are being upgraded to 1.24 with `kubeadm upgrade apply`, the command will remove the label `node-role.kubernetes.io/master` from existing control plane nodes. For new clusters, both the old taint `node-role.kubernetes.io/master:NoSchedule` and new taint `node-role.kuberne...

- In "large" clusters, kube-proxy in iptables mode will now sometimes
  leave unused rules in iptables for a while (up to `--iptables-sync-period`)
  before deleting them. This improves performance by not requiring it to
  check for stale rules on every sync. (In smaller clusters, it will still
  remove unused rules immediately once they are no longer used.)

   ([#123516](https://github.com/kubernetes/kubernetes/pull/123516), [@pohly](https://github.com/pohly))
- Fixed accidental enablement of the new alpha `optionalOldSelf` API field in `CustomResourceDefinition` validation rules, which should only have been allowed to be set when the `CRDValidationRatcheting` feature gate is enabled.
   ([#122329](https://github.com/kubernetes/kubernetes/pull/122329), [@jpbetz](https://github.com/jpbetz))

- Kubeadm: removed the toleration for the `node-role.kubernetes.io/master` taint from the CoreDNS deployment of `kubeadm`. With the 1.25 release of kubeadm the taint `node-role.kubernetes.io/master` is no longer applied to control plane nodes and the toleration for it can be removed with the release of 1.26. You can also perform the same toleration removal from...

- Fixes a race condition in the iptables mode of kube-proxy in 1.27 and later
  that could result in some updates getting lost (e.g., when a service gets a
  new endpoint, the rules for the new endpoint might not be added until
  much later). ([#122756](https://github.com/kubernetes/kubernetes/pull/122756), [@hakman](https://github.com/hakman)) [SIG Network]