## Introduction to 1.9.0

Kubernetes version 1.9 includes new features and enhancements, as well as fixes to identified issues. The release notes contain a brief overview of the important changes introduced in this release. The content is organized by Special Interest Group ([SIG](https://github.com/kubernetes/community/blob/master/sig-list.md)).

* Docker versions 1.10.3 - 1.12.3
  * Docker version 1.11.2 known issues
    - Kernel crash with Aufs storage driver on Debian Jessie ([#27885]((https://github.com/kubernetes/kubernetes/issues/27885))
      which can be identified by the [node problem detector](http://kubernetes.io/docs/admin/node-problem/)
    - Leaked File descriptors ([#275](https://github.com/docker/containerd/issues/275))

* You must now specify `Node.Spec.ConfigSource.ConfigMap.KubeletConfigKey` when using dynamic Kubelet config to tell the Kubelet which key of the `ConfigMap` identifies its config file. ([#59847](https://github.com/kubernetes/kubernetes/pull/59847), [@mtaufen](https://github.com/mtaufen))

* rkt: Convert image name to be a valid acidentifier ([#34375](https://github.com/kubernetes/kubernetes/pull/34375), [@euank](https://github.com/euank))

        *   Using `functools.wraps` on a function with different signature
        *   Using `functools.partial` with an invalid `tf.function` input
    *   `tf.function` now enforces input parameter names to be valid Python identifiers. Incompatible names are automatically sanitized similarly to existing SavedModel signature behavior.

- Audit events for API requests to deprecated API versions now include a `"k8s.io/deprecated": "true"` audit annotation. If a target removal release is identified, the audit event includes a `"k8s.io/removal-release": "<majorVersion>.<minorVersion>"` audit annotation as well. ([#92842](https://github.com/kubernetes/kubernetes/pull/92842), [@liggitt](https://github.com/liggitt)) [SIG API Machinery and Instrumentation]...

    * Docker version 1.11.2 known issues

        * Kernel crash with Aufs storage driver on Debian Jessie ([#27885](https://github.com/kubernetes/kubernetes/pull/27885)) which can be identified by the [node problem detector](https://kubernetes.io/docs/tasks/debug-application-cluster/monitor-node-health/)

        * Leaked File descriptors ([#275](https://github.com/docker/containerd/issues/275))

    * no shared pid namespace support
  * Docker version 1.11.2 known issues
    * Kernel crash with Aufs storage driver on Debian Jessie ([#27885](https://github.com/kubernetes/kubernetes/issues/27885))
      which can be identified by the [node problem detector](http://kubernetes.io/docs/admin/node-problem/)
    * Leaked File descriptors ([#275](https://github.com/docker/containerd/issues/275))

- User Assigned MSI (https://docs.microsoft.com/en-us/azure/active-directory/managed-service-identity/overview), which provides for managed identities, is now suppored for Kubernetes clusters on Azure. ([#66180](https://github.com/kubernetes/kubernetes/pull/66180), [@kkmsft](https://github.com/kkmsft))

pkg errors, func Unwrap(error) error
pkg go/constant, func Make(interface{}) Value
pkg go/constant, func Val(Value) interface{}
pkg go/token, func IsExported(string) bool
pkg go/token, func IsIdentifier(string) bool
pkg go/token, func IsKeyword(string) bool
pkg go/types, func CheckExpr(*token.FileSet, *Package, token.Pos, ast.Expr, *Info) error
pkg log, func Writer() io.Writer