- Added a path `/header?key=` to `agnhost netexec` allowing one to view what the header value is of the incoming request.

  Ex:
  ```
  $ curl -H "X-Forwarded-For: something" 172.17.0.2:8080/header?key=X-Forwarded-For
  something
  ```
   ([#107796](https://github.com/kubernetes/kubernetes/pull/107796), [@alexanderConstantinescu](https://github.com/alexanderConstantinescu))

```Python
async def do_something():
    try:
        yield something
    finally:
        some_cleanup()
```

...that way the `finally` block is run regardless of any exception that might happen.

### Features

- Some of the in-tree storage drivers indicate support for the `MetricsProvider` interface, but fail to configure this...

or `/etc/sysconfig/kubelet`, depending...

### Instrumentation

In v1.9 we focused on improving stability of the components owned by the SIG, including Heapster, Custom Metrics API adapters for Prometheus, and Stackdriver.

### Volumes
* StorageClass pre-installed and set as default on Azure, AWS, GCE, OpenStack, and vSphere.
  * This is something to pay close attention to if you’ve been using Kubernetes for a while, because it changes the default behavior of PersistentVolumeClaim objects on these clouds.

### SIG-autoscaling

SIG Autoscaling focused on improving the Horizontal Pod Autoscaling API and algorithm:
- We released autoscaling/v2beta2, which cleans up and unifies the API
- We improved readiness detection and smoothing to work well in a larger variety or use cases

### SIG-Azure

Sig Azure was focused on two primary new alpha features:
- Adding Azure Availability Zones support to cloud provider.