Convert site to Hugo (#8316)

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content/en/docs/reference/setup-tools/kubeadm/kubeadm-upgrade.md

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+---
+approvers:
+- mikedanese
+- luxas
+- jbeda
+title: kubeadm upgrade
+content_template: templates/concept
+---
+{{% capture overview %}}
+`kubeadm upgrade` is a user-friendly command that wraps complex upgrading logic behind one command, with support
+for both planning an upgrade and actually performing it. `kubeadm upgrade` can also be used for downgrading
+cluster if necessary.
+{{% /capture %}}
+
+{{% capture body %}}
+## kubeadm upgrade guidance
+
+Every upgrade process might be a bit different, so we've documented each minor upgrade process individually.
+Please check these documents out for more detailed how-to-upgrade guidance:
+
+ * [1.6 to 1.7 upgrades](/docs/tasks/administer-cluster/kubeadm-upgrade-1-7/)
+ * [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/)
+ * [1.9.x to 1.9.y HA cluster upgrades](/docs/tasks/administer-cluster/kubeadm-upgrade-ha/)
+
+## kubeadm upgrade plan {#cmd-upgrade-plan}
+{{< include "generated/kubeadm_upgrade_plan.md" >}}
+
+## kubeadm upgrade apply  {#cmd-upgrade-apply}
+{{< include "generated/kubeadm_upgrade_apply.md" >}}
+
+{{% /capture %}}
+
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+* [kubeadm config](kubeadm-config.md) if you initialized your cluster using kubeadm v1.7.x or lower, to configure your cluster for `kubeadm upgrade`
+{{% /capture %}}
+
+