Note: kubernetes doesn't support newer docker versions ("Version 17.03 is recommended... Versions 17.06+ might work, but have not yet been tested and verified by the Kubernetes node team" cf. [Bootstrapping Clusters with kubeadm](https://kubernetes.io/docs/setup/independent/install-kubeadm/#installing-docker)). Among other things kubelet currently breaks on docker's non-standard version numbering (it no longer uses semantic versioning). To ensure auto-updates don't break your cluster look into e.g. yum versionlock plugin or apt pin).
Note: The list of validated [docker versions](https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG-1.12.md) was updated to 1.11.1, 1.12.1, 1.13.1, 17.03, 17.06, 17.09, 18.06. The kubelet might break on docker's non-standard version numbering (it no longer uses semantic versioning). To ensure auto-updates don't break your cluster look into e.g. yum versionlock plugin or apt pin).
Note 2: rkt support as docker alternative is limited to control plane (etcd and
kubelet). Docker is still used for Kubernetes cluster workloads and network
Kusanagi9999
6 years ago