Initial draft of upgrade guide for kubeadm clusters.

In-place upgrades are supported between 1.6 and 1.7 releases.

Fixes kubernetes/kubeadm#278

_data/tasks.yml

@@ -111,6 +111,7 @@ toc:
   - docs/tasks/administer-cluster/guaranteed-scheduling-critical-addon-pods.md
   - docs/tasks/administer-cluster/cluster-management.md
   - docs/tasks/administer-cluster/upgrade-1-6.md
+  - docs/tasks/administer-cluster/kubeadm-upgrade-1-7.md
   - docs/tasks/administer-cluster/namespaces.md
   - docs/tasks/administer-cluster/namespaces-walkthrough.md
   - docs/tasks/administer-cluster/dns-horizontal-autoscaling.md

docs/setup/independent/create-cluster-kubeadm.md

@@ -386,6 +386,11 @@ kubeadm reset
 If you wish to start over simply run `kubeadm init` or `kubeadm join` with the
 appropriate arguments.
 
+## Upgrading
+
+Instructions for upgrading kubeadm clusters can be found
+[here](/docs/tasks/administer-cluster/kubeadm-upgrade-1-7/).
+
 ## Explore other add-ons
 
 See the [list of add-ons](/docs/concepts/cluster-administration/addons/) to explore other add-ons,

docs/tasks/administer-cluster/kubeadm-upgrade-1-7.md

@@ -0,0 +1,66 @@
+---
+assignees:
+- pipejakob
+title: Upgrading kubeadm clusters from 1.6 to 1.7
+redirect_from:
+- "/docs/admin/kubeadm-upgrade-1-7/"
+- "/docs/admin/kubeadm-upgrade-1-7.html"
+---
+
+* TOC
+{:toc}
+
+This guide is for upgrading kubeadm clusters from version 1.6.x to 1.7.x.
+Upgrades are not supported for clusters lower than 1.6, which is when kubeadm
+became Beta.
+
+**WARNING**: These instructions will **overwrite** all of the resources managed
+by kubeadm (static pod manifest files, service accounts and RBAC rules in the
+`kube-system` namespace, etc.), so any customizations you may have made to these
+resources after cluster setup will need to be reapplied after the upgrade. The
+upgrade will not disturb other static pod manifest files or objects outside the
+`kube-system` namespace.
+
+1. Back up `/etc/kubernetes`.
+
+       sudo cp -r /etc/kubernetes /root/kubernetes-backup
+
+2. Upgrade system packages.
+
+   Upgrade your OS packages for kubectl, kubeadm, kubelet, and kubernetes-cni.
+
+   a. On Debian, this can be accomplished with:
+
+       sudo apt-get update
+       sudo apt-get upgrade
+
+   b. On CentOS/Fedora, you would instead run:
+
+       sudo yum update
+
+3. Restart kubelet.
+
+       sudo systemctl restart kubelet
+
+4. Delete the `kube-proxy` DaemonSet.
+
+   Although most components are automatically upgraded by the next step,
+   `kube-proxy` currently needs to be manually deleted so it can be recreated at
+   the correct version:
+
+       sudo KUBECONFIG=/etc/kubernetes/admin.conf kubectl delete daemonset kube-proxy -n kube-system
+
+5. Perform kubeadm upgrade.
+
+       sudo kubeadm init --skip-preflight-checks --kubernetes-version <DESIRED_VERSION>
+
+   For instance, if you want to upgrade to `1.7.0`, you would run:
+
+       sudo kubeadm init --skip-preflight-checks --kubernetes-version v1.7.0
+
+6. Upgrade CNI provider.
+
+   Your CNI provider might have its own upgrade instructions to follow now.
+   Check the [addons](/docs/concepts/cluster-administration/addons/) page to
+   find your CNI provider and see if there are additional upgrade steps
+   necessary.