Add Gardener project to platform-setup (#3734)

content/docs/setup/kubernetes/prepare/platform-setup/gardener/index.md

@@ -0,0 +1,76 @@
+---
+title: Kubernetes Gardener
+description: Instructions to setup a Gardener cluster for Istio.
+weight: 15 
+skip_seealso: true
+keywords: [platform-setup,kubernetes,gardener,sap]
+---
+
+## Bootstrapping Gardener
+
+To set up your own [Gardener](https://gardener.cloud), see the
+[documentation](https://github.com/gardener/gardener/blob/master/docs/README.md)
+or have a look at the
+[landscape-setup-template](https://github.com/gardener/landscape-setup-template)
+project. To learn more about this open source project, read the
+[blog on kubernetes.io](https://kubernetes.io/blog/2018/05/17/gardener/).
+
+### Install and configure `kubectl`
+
+1.  If you already have `kubectl` CLI, run `kubectl version --short` to check
+    the version. You need v1.10 or newer. If your `kubectl` is older, follow the
+    next step to install a newer version.
+
+1.  [Install the kubectl CLI](https://kubernetes.io/docs/tasks/tools/install-kubectl/#install-kubectl).
+
+### Access Gardener
+
+1.  Create a project in the Gardener dashboard. This will essentially create a
+    Kubernetes namespace with the name `garden-<my-project>`.
+
+1.  [Configure access to your Gardener project](https://kubernetes.io/docs/tasks/tools/install-kubectl/#configure-kubectl)
+    using a kubeconfig. If you are not the Gardener Administrator already, you
+    can create a technical user in the Gardener dashboard: go to the "Members"
+    section and add a service account. You can then download the kubeconfig for
+    your project. You can skip this step if you create your cluster using the
+    user interface; it is only needed for programmatic access, make sure you set
+    `export KUBECONFIG=garden-my-project.yaml` in your shell.
+    ![Download kubeconfig for Gardener](images/gardener_service_account.png "downloading the kubeconfig using a service account")
+
+### Creating a Kubernetes cluster
+
+You can create your cluster using `kubectl` cli by providing a cluster
+specification yaml file. You can find an example for GCP
+[here](https://github.com/gardener/gardener/blob/master/example/90-shoot-gcp.yaml).
+Make sure the namespace matches that of your project. Then just apply the
+prepared so-called "shoot" cluster crd with kubectl:
+
+{{< text bash >}}
+$ kubectl apply --filename my-cluster.yaml
+{{< /text >}}
+
+The easier alternative is to create the cluster following the cluster creation
+wizard in the Gardener dashboard:
+![shoot creation](images/gardener_shoot_creation.png "shoot creation via the dashboard")
+
+### Configure kubectl for your cluster
+
+You can now download the kubeconfig for your freshly created cluster in the
+Gardener dashboard or via cli as follows:
+
+{{< text bash >}}
+$ kubectl --namespace shoot--my-project--my-cluster get secret kubecfg --output jsonpath={.data.kubeconfig} | base64 --decode > my-cluster.yaml
+{{< /text >}}
+
+This kubeconfig file has full administrators access to you cluster. For the rest
+of this guide be sure you have `export KUBECONFIG=my-cluster.yaml` set.
+
+## Cleaning up
+
+Use the Gardener dashboard to delete your cluster, or execute the following with
+kubectl pointing to your `garden-my-project.yaml` kubeconfig:
+
+{{< text bash >}}
+$ kubectl --kubeconfig garden-my-project.yaml --namespace garden--my-project annotate shoot my-cluster confirmation.garden.sapcloud.io/deletion=true
+$ kubectl --kubeconfig garden-my-project.yaml --namespace garden--my-project delete shoot my-cluster
+{{< /text >}}