- Kubelet now exposes `/debug/flags/v` to allow dynamically setting glog logging level.  For example, to change glog level to 3, you only have to send a PUT request like `curl -X PUT http://127.0.0.1:8080/debug/flags/v -d "3"`. ([#64601](https://github.com/kubernetes/kubernetes/pull/64601), [@hzxuzhonghu](https://github.com/hzxuzhonghu))

### SIG OpenStack

* Exposed `/debug/flags/v` to allow dynamically set glog logging level.  For example, to change glog level to 3, send a PUT request such as `curl -X PUT http://127.0.0.1:8080/debug/flags/v -d "3"`. ([#63777](https://github.com/kubernetes/kubernetes/pull/63777), [@hzxuzhonghu](https://github.com/hzxuzhonghu))

The only client
this is known to affect is curl when you use -d with JSON but don't set a
content type, helpfully sends "application/x-www-urlencoded", which is not
correct.
Other client authors should double check that you are sending proper
accept and content type headers, or set no value (in which case JSON is the
default).
An example using curl:
<code>curl -H "Content-Type: application/json" -XPOST -d

* Make watch cache treat resourceVersion consistent with uncached watch ([#24008](https://github.com/kubernetes/kubernetes/pull/24008), [@liggitt](https://github.com/liggitt))

### Other notable changes

* Trusty: Add retry in curl commands ([#24749](https://github.com/kubernetes/kubernetes/pull/24749), [@andyzheng0831](https://github.com/andyzheng0831))

- 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
  ```