* Make addon-manager cross-platform and use it with hyperkube ([#25631](https://github.com/kubernetes/kubernetes/pull/25631), [@luxas](https://github.com/luxas))
* kubelet: Optionally, have kubelet exit if lock file contention is observed, using --exit-on-lock-contention flag ([#25596](https://github.com/kubernetes/kubernetes/pull/25596), [@derekparker](https://github.com/derekparker))

When the **container** is started and running (started from a **container image**) it could create or change files, environment variables, etc. Those changes will exist only in that container, but would not persist in the underlying container image (would not be saved to disk).

A container image is comparable to the **program** file and contents, e.g. `python` and some file `main.py`.

			return objInfo, PreConditionFailed{}
		}
		if err != nil && !isErrVersionNotFound(err) && !isErrObjectNotFound(err) {
			return objInfo, err
		}

		// if object doesn't exist return error for If-Match conditional requests
		// If-None-Match should be allowed to proceed for non-existent objects
		if err != nil && opts.HasIfMatch && (isErrObjectNotFound(err) || isErrVersionNotFound(err)) {

    * Add validation for upstreamNameserver port.
    * Update go version to 1.9.3.
* CRI: define the mount behavior when host path does not exist: runtime should report error if the host path doesn't exist ([#61460](https://github.com/kubernetes/kubernetes/pull/61460), [@feiskyer](https://github.com/feiskyer))

		{"---", "", "", "", 0, ListObjectsInfo{}, BucketNameInvalid{Bucket: "---"}, false},
		{"ad", "", "", "", 0, ListObjectsInfo{}, BucketNameInvalid{Bucket: "ad"}, false},
		// Valid bucket names, but they do not exist (6-8).
		{"volatile-bucket-1", "", "", "", 1000, ListObjectsInfo{}, BucketNotFound{Bucket: "volatile-bucket-1"}, false},
		{"volatile-bucket-2", "", "", "", 1000, ListObjectsInfo{}, BucketNotFound{Bucket: "volatile-bucket-2"}, false},

              && entryKey != null
              && map.keyEquivalence.equivalent(key, entryKey)) {
            // If the value disappeared, this entry is partially collected,
            // and we should pretend like it doesn't exist.
            V entryValue = e.getValue();
            if (entryValue == null) {
              if (isCollected(e)) {
                int newCount = this.count - 1;
                ++modCount;

- The `kubectl patch` command no longer exits with exit code 1 when a redundant patch results in a no-op ([#66725](https://github.com/kubernetes/kubernetes/pull/66725), [@juanvallejo](https://github.com/juanvallejo))

				// such an intersection means that bucket exists on etcd.
				// but if we do see a difference with local domain IPs with
				// hostSlice from etcd then we should update with newer
				// domainIPs, we proceed to do that here.
				bucketsToBeUpdated.Add(bucket)
				continue
			}

			// No IPs seem to intersect, this means that bucket exists but has
			// different IP addresses perhaps from a different deployment.

      assertThat(right.takeEvent()::class).isEqualTo(expectedEvent::class)
      assertThat(right.eventSequence).isEmpty()
    }
  }

  /** Listeners added with [Call.addEventListener] don't exist on clones of that call. */
  @Test
  fun clonedCallDoesNotHaveAddedEventListeners() {
    assumeTrue(listenerInstalledOn != ListenerInstalledOn.Client)

    server.enqueue(
      MockResponse

* AWS kube-up: tolerate a lack of ephemeral volumes ([#23776](https://github.com/kubernetes/kubernetes/pull/23776), [@justinsb](https://github.com/justinsb))
* Fix so setup-files don't recreate/invalidate certificates that already exist ([#23550](https://github.com/kubernetes/kubernetes/pull/23550), [@luxas](https://github.com/luxas))



# v1.2.1

[Documentation](http://kubernetes.github.io) & [Examples](http://releases.k8s.io/release-1.2/examples)