* The `generate-internal-groups.sh` script in k8s.io/code-generator will generate OpenAPI definitions by default in `pkg/generated/openapi`. Additional API group dependencies can be added via `OPENAPI_EXTRA_PACKAGES=<group>/<version> <group2>/<version2>...`.

  are now in the apps/v1beta2 group and version.

- The apps/v1beta2 group version adds a Scale subresource for the StatefulSet
kind.

- All kinds in the apps/v1beta2 group version add a corresponding conditions
  kind.

#### Behavioral Changes

 - For all kinds in the API group version, a spec.selector default value is no longer

Kubelet flag `--enforce-node-allocatable` with a default value of `pods` is added which will make kubelet create a top level cgroup for all pods to enforce Node Allocatable. Optionally, `system-reserved` & `kube-reserved` values can also be specified separated by comma to enforce node allocatable on cgroups specified via `--system-reserved-cgroup` & `--kube-reserved-cgroup` respectively. Note the default value of the latter flags are "". ([#41234](https://github.com/kubernetes/kubernetes/pull/41234),...

*   OpenStack security group support has been beefed up  ([#50836](https://github.com/kubernetes/kubernetes/pull/50836),[ @FengyunPan](https://github.com/FengyunPan)):
    *   Kubernetes will now automatically determine the security group for the node
    *   Nodes can now belong to multiple security groups

### **Scheduling**

#### **Hardware Accelerators**

* kubeadm now detects the Docker cgroup driver and starts the kubelet with the matching driver. This eliminates a common error experienced by new users in when the Docker cgroup driver is not the same as the one set for the kubelet due to different Linux distributions setting different cgroup drivers for Docker, making it hard to start the kubelet properly.

        if (opLambda != null) {
            opLambda.callback(builder);
        }
    }

    public void setGroups_Regexp(String groups) {
        setGroups_Regexp(groups, null);
    }

    public void setGroups_Regexp(String groups, ConditionOptionCall<RegexpQueryBuilder> opLambda) {
        RegexpQueryBuilder builder = regRegexpQ("groups", groups);

- Fixed AWS Cloud Provider attempting to delete LoadBalancer security group it didn’t provision, and fixed AWS Cloud Provider creating a default LoadBalancer security group even if annotation `service.beta.kubernetes.io/aws-load-balancer-security-groups` is present because the intended behavior of aws-load-balancer-security-groups is to replace all security groups assigned to the load balancer. ([#84265](https://github.com/kubernetes/kubernetes/pull/84265), [@bhag...

* The kube-apiserver discovery APIs (for example, `/apis`) return information about the API groups being served, and can change dynamically.
During server startup, prior to the server reporting healthy (via `/healthz`), not all API groups may be reported.
Wait for the server to report healthy (via `/healthz`) before depending on the information provided by the discovery APIs.

* The `PodSecurityPolicy` API has been moved to the `policy/v1beta1` API group. The `PodSecurityPolicy` API in the `extensions/v1beta1` API group is deprecated and will be removed in a future release. Authorizations for using pod security policy resources should change to reference the `policy` API group after upgrading to 1.11. ([#54933](https://github.com/kubernetes/kubernetes/pull/54933), [@php-coder](https://github.com/php-coder))

`kubeadm`: a separate "super-admin.conf" file is now deployed. The User in `admin.conf` is now bound to a new RBAC Group `kubeadm:cluster-admins` that has `cluster-admin` `ClusterRole` access. The User in `super-admin.conf` is now bound to the `system:masters` built-in super-powers / break-glass Group that can bypass RBAC. Before this change, the default `admin.conf` was bound to `system:masters` Group, which was undesired. Executing `kubeadm init phase kubeconfig all` or just `kubeadm init` will now generate...