- Ensure Azure availability zone is always in lower cases. ([#89722](https://github.com/kubernetes/kubernetes/pull/89722), [@feiskyer](https://github.com/feiskyer)) [SIG Cloud Provider]

    assertThat(consumingIterator.next()).isEqualTo("b");
    assertThat(list).isEmpty();

    assertFalse(consumingIterator.hasNext());
  }

  @GwtIncompatible // ?
  // TODO: Figure out why this is failing in GWT.
  public void testConsumingIterator_duelingIterators() {
    // Test data
    List<String> list = Lists.newArrayList("a", "b");

    // Test & Verify

 *  The challenge's scheme and realm are now non-null. If you are calling
    `new Challenge(scheme, realm)` you must provide non-null values. These were
    never null in challenges created by OkHttp, but could have been null in
    application code that creates challenges.

 *  New: The `TlsVersion` of a `Handshake` is now non-null. If you are calling
    `Handshake.get()` with a null TLS version, you must instead now provide a

        assertEquals("custom-session-123", pythonJob.sessionId);
    }

    // Test execute with process failure
    @Test
    public void test_execute_processFailure() {
        pythonJob.filename("failing.py");

        testProcessHelper.exitValue = 1;
        testProcessHelper.processOutput = "Error: Script failed";

        String result = pythonJob.execute();

        assertNotNull(result);

- Fix the bug which could result in Job status updates failing with the error:
  status.startTime: Required value: startTime cannot be removed for unsuspended job

* [stable] Expose storage usage metrics

  * The available capacity of a given Persistent Volume (PV) is available by calling the Kubernetes metrics API.

* [stable] Volume plugin metrics

  * Success and latency metrics for all Kubernetes calls are available by calling the Kubernetes metrics API. You can request volume operations, including mount, unmount, attach, detach, provision, and delete.

  - [alpha] ingress has alpha support for a single master multi zone cluster ([docs](http://kubernetes.io/docs/user-guide/ingress.md#failing-across-availability-zones)) ([kubernetes/features#52](https://github.com/kubernetes/enhancements/issues/52))
- **Network**

    * !!! [1215 15:42:56] Timed out waiting for apiserver:  to answer at https://localhost:6443/version; tried 10 waiting 1 between each

- Fixed spurious error messages about failing to clean up iptables rules when using iptables 1.8. ([#77303](https://github.com/kubernetes/kubernetes/pull/77303), [@danwinship](https://github.com/danwinship))

          }
        }
      } finally {
        unlock();
        postWriteCleanup();
      }

      if (createNewEntry) {
        try {
          // Synchronizes on the entry to allow failing fast when a recursive load is
          // detected. This may be circumvented when an entry is copied, but will fail fast most
          // of the time.
          synchronized (e) {