* Allow configuration of a single security group for ELBs ([#45500](https://github.com/kubernetes/kubernetes/pull/45500), [@nbutton23](https://github.com/nbutton23))

  * Remove check that forces loadBalancerSourceRanges to be 0.0.0.0/0. ([#38636](https://github.com/kubernetes/kubernetes/pull/38636), [@dhawal55](https://github.com/dhawal55))

- kubeadm: removed the deprecated flag `--experimental-output`, please use the flag `--output` instead that serves the same purpose. Affected commands are: `kubeadm config images list`, `kubeadm token list`, `kubeadm upgrade plan`, `kubeadm certs check-expiration`. ([#126914](https://github.com/kubernetes/kubernetes/pull/126914), [@carlory](https://github.com/carlory))...

  the garbage collector starts to manage it.


#### Monitoring/Prometheus
* [action required] The WATCHLIST calls are now reported as WATCH verbs in prometheus for the apiserver_request_* series.  A new "scope" label is added to all apiserver_request_* values that is either 'cluster', 'resource', or 'namespace' depending on which level the query is performed at.([#52237](https://github.com/kubernetes/kubernetes/pull/52237))

- `apidiscovery.k8s.io/v2beta1` API group is disabled by default ([#130347](https://github.com/kubernetes/kubernetes/pull/130347), [@Jefftree](https://github.com/Jefftree)) [SIG API Machinery and Testing]
- `kubectl apply` now coerces `null` values for labels and annotations in manifests to empty string values, 

### CSI Volume health monitoring
 

     * ensure that completed write operations performed by other threads are noticed. For most
     * purposes, the "count" field, tracking the number of elements, serves as that volatile
     * variable ensuring visibility. This is convenient because this field needs to be read in many
     * read operations anyway:
     *

  - The `export` query parameter for list API calls, deprecated since v1.14, will be removed in v1.18.
  - The `series.state` field in the events.k8s.io/v1beta1 Event API is deprecated and will be removed in v1.18 ([#75987](https://github.com/kubernetes/kubernetes/pull/75987), [@yastij](https://github.com/yastij))

- kubeadm

* Splits Juju Charm layers into master/worker roles ([#40324](https://github.com/kubernetes/kubernetes/pull/40324), [@chuckbutler](https://github.com/chuckbutler))
    * Adds support for 1.5.x series of Kubernetes
    * Introduces a tactic for keeping templates in sync with upstream eliminating template drift
    * Adds CNI support to the Juju Charms
    * Adds durable storage support to the Juju Charms

- Update the Event series starting count when emitting isomorphic events from 1 to 2. ([#119375](https://github.com/kubernetes/kubernetes/pull/119375), [@dgrisonnet](https://github.com/dgrisonnet)) [SIG API Machinery and Testing]

## Dependencies

- Ubuntu 18.04 (Bionic) series has been added to Juju charms ([#65644](https://github.com/kubernetes/kubernetes/pull/65644), [@tvansteenburgh](https://github.com/tvansteenburgh))