- Kubeadm: avoid panicing if the user has malformed the kubeconfig in the cluster-info config map to not include a valid current context. Include proper validation at the appropriate locations and throw errors instead. ([#134724](https://github.com/kubernetes/kubernetes/pull/134724), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]

### API Change

*   `conversion-gen` is now usable in a context without a vendored k8s.io/kubernetes. The Kubernetes core API is removed from `default extra-peer-dirs`. ([#54394](https://github.com/kubernetes/kubernetes/pull/54394),[ @sttts](https://github.com/sttts))

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 certificates.

The kubeadm configuration file API is moving from v1beta1 to v1beta2 in 1.15.

  termination message log file. The termination message file is now properly
  readable for end users and has a maximum size (4k bytes) to prevent abuse.
  Each pod may have up to 12k bytes of termination messages before the contents
  of each will be truncated.
* Do not delete pod objects until all its compute resource footprint has been
  reclaimed.
  - This feature prevents the node and scheduler from oversubscribing resources

   * loading, or expired. Unlike {@link Segment#getLiveValue} this method does not attempt to clean
   * up stale entries. As such it should only be called outside a segment context, such as during
   * iteration.
   */
  @Nullable V getLiveValue(ReferenceEntry<K, V> entry, long now) {
    if (entry.getKey() == null) {
      return null;
    }

* Add get/delete cluster, delete context to kubectl config ([#29821](https://github.com/kubernetes/kubernetes/pull/29821), [@alexbrand](https://github.com/alexbrand))

      return comparator;
    }
    return (Comparator<E>) Ordering.natural();
  }

  /**
   * Returns a live {@link Map} view whose keys are the contents of {@code set} and whose values are
   * computed on demand using {@code function}. To get an immutable <i>copy</i> instead, use {@link
   * #toMap(Iterable, Function)}.
   *

      return comparator;
    }
    return (Comparator<E>) Ordering.natural();
  }

  /**
   * Returns a live {@link Map} view whose keys are the contents of {@code set} and whose values are
   * computed on demand using {@code function}. To get an immutable <i>copy</i> instead, use {@link
   * #toMap(Iterable, Function)}.
   *

- Resolves a spurious "Unknown discovery response content-type" error in client-go discovery requests by tolerating extra content-type parameters in API responses ([#117571](https://github.com/kubernetes/kubernetes/pull/117571), [@seans3](https://github.com/seans3)) [SIG API Machinery]