## Was ist ein Container?

Container (hauptsächlich Linux-Container) sind eine sehr **leichtgewichtige** Möglichkeit, Anwendungen einschließlich aller ihrer Abhängigkeiten und erforderlichen Dateien zu verpacken und sie gleichzeitig von anderen Containern (anderen Anwendungen oder Komponenten) im selben System isoliert zu halten.

 * <td>&times;</td>
 * </tr>
 * </table>
 * <p>
 * Methods that take {@link InputStream}/{@link OutputStream}/{@link Reader}/{@link Writer} as arguments do not call {@link Closeable#close()} on the arguments. The caller is responsible for closing them.
 * </p>
 * <p>
 * Any {@link IOException} thrown by these methods is wrapped and thrown as an {@link IORuntimeException}.
 * </p>
 *
 * @author koichik
 */

- Filter published OpenAPI schema by making nullable, required fields non-required in order to avoid kubectl to wrongly reject null values. ([#85722](https://github.com/kubernetes/kubernetes/pull/85722), [@sttts](https://github.com/sttts)) [SIG API Machinery]

  * Use optimized image based on Jessie by default
  * Add support for Ubuntu Wily
  * Master is configured with automatic restart-on-failure, via CloudWatch
  * Bootstrap reworked to be more similar to GCE; better supports reboots/restarts
  * Use an elastic IP for the master by default
  * Experimental support for node spot instances (set NODE\_SPOT\_PRICE=0.05)

#### GCE

    // Give the server time to enact the socket policy if it's one that could happen after the
    // client has received the response.
    Thread.sleep(500)
    val response2 = getResponse(newRequest("/b"))
    response1.body
      .source()
      .timeout()
      .timeout(100, TimeUnit.MILLISECONDS)
    assertContent("This comes after a busted connection", response2)

 * creation methods appear to adhere doggedly to the original intent of the "mapped" address: all
 * "mapped" addresses return {@link Inet4Address} objects.
 *
 * <p>For added safety, it is common for IPv6 network operators to filter all packets where either
 * the source or destination address appears to be a "compat" or "mapped" address. Filtering
 * suggestions usually recommend discarding any packets with source or destination addresses in the

### kubeadm
* A new label and taint is used for marking the master. The label is `node-role.kubernetes.io/master=""` and the taint has the effect `NoSchedule`. Tolerate the `node-role.kubernetes.io/master="":NoSchedule` taint to schedule a workload on the master (a networking DaemonSet for example).
* The kubelet API is now secured, only cluster admins are allowed to access it.

- Scheduler changes its logic of calculating `evaluatedNodes` from "contains the number of nodes that filtered out by PreFilterResult and Filter plugins" to "the number of nodes filtered out by Filter plugins only". ([#124735](https://github.com/kubernetes/kubernetes/pull/124735), [@AxeZhan](https://github.com/AxeZhan))
- Services implemented a field selector for the ClusterIP and Type fields.

        bool((must, should, mustNot, filter) -> {
            filteredLambda.callback(must, filter);
        }, opLambda);
    }

    public void not(OperatorCall<UserCQ> notLambda) {
        not(notLambda, null);
    }

    public void not(final OperatorCall<UserCQ> notLambda, final ConditionOptionCall<BoolQueryBuilder> opLambda) {
        bool((must, should, mustNot, filter) -> notLambda.callback(mustNot), opLambda);
    }

Release notes of older releases can be found in:
- [CHANGELOG-1.2.md](https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.2.md)
- [CHANGELOG-1.3.md](https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.3.md)