Update kubeadm-upgrade.md (#7335)

Added link to 1.9 upgrades. 

I am uncertain about the right document for `1.8.x` to `1.8.y` upgrades, as both these documents state that is their purpose:
- https://kubernetes.io/docs/tasks/administer-cluster/kubeadm-upgrade-1-8/
- https://kubernetes.io/docs/tasks/administer-cluster/kubeadm-upgrade-1-9/
So I have left the link for that scenario as it is.
This commit is contained in:
Martin Mosegaard Amdisen
2018-02-24 22:18:44 +01:00
committed by k8s-ci-robot
parent a49701cf4b
commit 4e248ae8f4
@@ -21,6 +21,8 @@ Please check these documents out for more detailed how-to-upgrade guidance:
* [1.7.x to 1.7.y upgrades](/docs/tasks/administer-cluster/kubeadm-upgrade-1-8/)
* [1.7 to 1.8 upgrades](/docs/tasks/administer-cluster/kubeadm-upgrade-1-8/)
* [1.8.x to 1.8.y upgrades](/docs/tasks/administer-cluster/kubeadm-upgrade-1-8/)
* [1.8.x to 1.9.x upgrades](/docs/tasks/administer-cluster/kubeadm-upgrade-1-9/)
* [1.9.x to 1.9.y upgrades](/docs/tasks/administer-cluster/kubeadm-upgrade-1-9/)
## kubeadm upgrade plan {#cmd-upgrade-plan}
{% include_relative generated/kubeadm_upgrade_plan.md %}