* `kubeadm join` is now blocking on the kubelet performing the TLS Bootstrap properly. Earlier, `kubeadm join` only did the discovery part and exited successfully without checking that the kubelet actually started properly and performed the TLS bootstrap correctly. Now, as kubeadm runs some post-join steps (for example, annotating the Node API object with the CRISocket), `kubeadm join` is now waiting for the kubelet to perform the TLS Bootstrap,...

- Kubeadm: The ClusterStatus struct present in the kubeadm-config ConfigMap is deprecated and will be removed on a future version. It is going to be maintained by kubeadm until it gets removed. The same information can be found on `etcd` and `kube-apiserver` pod annotations, `kubeadm.kubernetes.io/etcd.advertise-client-urls` and `kubeadm.kubernetes.io/kube-apiserver.advertise-address.endpoint` respectively. ([#87656](...

- Kubeadm: Fix a bug where kubeadm cannot parse kubelet's version if the latter dumps logs on the standard error. ([#85351](https://github.com/kubernetes/kubernetes/pull/85351), [@rosti](https://github.com/rosti))

- Kubeadm: Used output/v1alpha3 to print structural output for the commands "kubeadm config images list" and "kubeadm token list". ([#124464](https://github.com/kubernetes/kubernetes/pull/124464), [@carlory](https://github.com/carlory))

Kubeadm: Expose the `kubeadm join` workflow as phases

- Kubeadm: remove the deprecated command "kubeadm alpha kubeconfig". Please use "kubeadm kubeconfig" instead. ([#101938](https://github.com/kubernetes/kubernetes/pull/101938), [@knight42](https://github.com/knight42)) [SIG Cluster Lifecycle]

Executing `kubeadm init phase kubeconfig all` or just `kubeadm init` will now generate the new `super-admin.conf` file. The cluster admin can then decide to keep the file present on a node host or move it to a safe location. `kubadm certs renew` will renew the certificate in `super-admin.conf` to one year if the file exists; if it does not exist a "MISSING" note will be printed. `kubeadm upgrade apply` for this release will migrate this particular node to the two file setup. Subsequent kubeadm releases...

- kubeadm has graduated `kubeadm alpha phase` commands to `kubeadm init phase`. This means that the phases of creating a control-plane node are now tightly integrated as part of the `init`...

ironment/tools/kubeadm/high-availability/). An entire new test suite has been created specifically for ensuring these features will stay stable over time.

Certificate management has become more robust in 1.15, with kubeadm now seamlessly rotating all your certificates (on upgrades) before they expire. Check the [kubeadm documentation](https://github.com/kubernetes/website/blob/dev-1.15/content/en/docs/reference/setup-tools/kubeadm/kubeadm-alpha.md) for information on how to manage your...

- Improved air-gapped and offline support
  - kubeadm now handles air-gapped environments by using the local client version as a fallback.
  - Some kubeadm commands are now allowed to work in a completely offline mode.
- Certificate handling improvements:
  - Renew certs as part of upgrade.
  - New `kubeadm alpha phase certs renew` command for renewing certificates.