*  Docker 1.10.3 contains [backports provided by RedHat](https://github.com/docker/docker/compare/v1.10.3...runcom:docker-1.10.3-stable) for known issues
  * Docker versions as old as may 1.9.1 work with [known issues](CHANGELOG.md#191) but this is not guaranteed
* rkt version 1.21.0
  * known issues with the rkt runtime are [listed here](http://kubernetes.io/docs/getting-started-guides/rkt/notes/)
* etcd version 2.2.1

## Action Required Before Upgrading

- If you are using Kubernetes to manage `docker` containers, please be aware Kubernetes has been validated to work with docker 1.9.1, docker 1.11.2 (#23397), and docker 1.12.0 (#28698)