A previous release built hyperkube using the debian-hyperkube-base@v1.0.0,
    which was updated to address a CVE in the CNI plugins.
    
    A side-effect of using this new image was that the networking packages
    (namely `iptables`) drifted from the versions used in the kube-proxy images.
  
    The following issues were filed on kube-proxy failures when using hyperkube:

  Don't use these flags. Using deprecated flags causes the server to print a warning. Using a removed flag causes the server to abort the startup.

* The following deprecated flags were removed from `kubelet`:

  * `api-servers` - add apiserver addresses to the kubeconfig file instead.

    * Please convert your `v1alpha1` configuration files to `v1alpha2` using the
    * `kubeadm config migrate` command of kubeadm v1.11.x

- Fixes a bug where Services using finalizers may hold onto ClusterIP and/or NodePort allocated resources for longer than expected if the finalizer is removed using the status subresource ([#120654](https://github.com/kubernetes/kubernetes/pull/120654), [@aojea](https://github.com/aojea)) [SIG Testing]
- Revised the logic for DaemonSet rolling update to exclude nodes if scheduling constraints are not met.

  
    A previous release built hyperkube using the debian-hyperkube-base@v1.0.0,
    which was updated to address a CVE in the CNI plugins.
    
    A side-effect of using this new image was that the networking packages
    (namely `iptables`) drifted from the versions used in the kube-proxy images.
  
    The following issues were filed on kube-proxy failures when using hyperkube:

    *   Support for IPv6 Kubernetes control and data planes.
    *   Support for Kubernetes IPv6 cluster deployments using kubeadm.
    *   Support for the iptables kube-proxy backend using ip6tables.
    *   Relies on CNI 0.6.0 binaries for IPv6 pod networking.
    *   Adds IPv6 support for kube-dns using SRV records.
    *   Caveats

- DaemonSets accept a MaxSurge integer or percent on their rolling update strategy that will launch the updated pod on nodes and wait for those pods to go ready before marking the old out-of-date pods as deleted. This allows workloads to avoid downtime during upgrades when deployed using DaemonSets. This feature is alpha and is behind the DaemonSetUpdateSurge feature gate. ([#96441](https://github.com/kubernetes/kubernetes/pull/96441),...

- Fixes creationTimestamp: null causing unnecessary writes to etcd ([#116865](https://github.com/kubernetes/kubernetes/pull/116865), [@alexzielenski](https://github.com/alexzielenski)) [SIG API Machinery and Testing]
- Revised the logic for DaemonSet rolling update to exclude nodes if scheduling constraints are not met.

* In-place node upgrades to this release from versions 1.7.14, 1.8.9, and 1.9.4 are not supported if using subpath volumes with PVCs.  Such pods should be drained from the node first.

- kube-scheduler dropped support for configuration files with apiVersion `componentconfig/v1alpha1`. Ensure kube-scheduler is configured using command-line flags or a configuration file with apiVersion `kubescheduler.config.k8s.io/v1alpha1`...