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docs/05-kubernetes-configuration-files.md

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+# Generating Kubernetes Configuration Files for Authentication
+
+In this lab you will generate [Kubernetes configuration files](https://kubernetes.io/docs/concepts/configuration/organize-cluster-access-kubeconfig/), also known as kubeconfigs, which enable Kubernetes clients to locate and authenticate to the Kubernetes API Servers.
+
+## Client Authentication Configs
+
+In this section you will generate kubeconfig files for the `kubelet` and `kube-proxy` clients.
+
+> The `scheduler` and `controller manager` access the Kubernetes API Server locally over an insecure API port which does not require authentication. The Kubernetes API Server's insecure port is only enabled for local access.
+
+### Kubernetes Public IP Address
+
+Each kubeconfig requires a Kubernetes API Server to connect to. To support high availability the IP address assigned to the external load balancer fronting the Kubernetes API Servers will be used.
+
+Retrieve the `kubernetes-the-hard-way` static IP address:
+
+```
+KUBERNETES_PUBLIC_ADDRESS=$(gcloud compute addresses describe kubernetes-the-hard-way \
+  --region $(gcloud config get-value compute/region) \
+  --format 'value(address)')
+```
+
+### The kubelet Kubernetes Configuration File
+
+When generating kubeconfig files for Kubelets the client certificate matching the Kubelet's node name must be used. This will ensure Kubelets are properly authorized by the Kubernetes [Node Authorizer](https://kubernetes.io/docs/admin/authorization/node/).
+
+Generate a kubeconfig file for each worker node:
+
+```
+for instance in worker-0 worker-1 worker-2; do
+  kubectl config set-cluster kubernetes-the-hard-way \
+    --certificate-authority=ca.pem \
+    --embed-certs=true \
+    --server=https://${KUBERNETES_PUBLIC_ADDRESS}:6443 \
+    --kubeconfig=${instance}.kubeconfig
+
+  kubectl config set-credentials system:node:${instance} \
+    --client-certificate=${instance}.pem \
+    --client-key=${instance}-key.pem \
+    --embed-certs=true \
+    --kubeconfig=${instance}.kubeconfig
+
+  kubectl config set-context default \
+    --cluster=kubernetes-the-hard-way \
+    --user=system:node:${instance} \
+    --kubeconfig=${instance}.kubeconfig
+
+  kubectl config use-context default --kubeconfig=${instance}.kubeconfig
+done
+```
+
+Results:
+
+```
+worker-0.kubeconfig
+worker-1.kubeconfig
+worker-2.kubeconfig
+```
+
+### The kube-proxy Kubernetes Configuration File
+
+Generate a kubeconfig file for the `kube-proxy` service:
+
+```
+kubectl config set-cluster kubernetes-the-hard-way \
+  --certificate-authority=ca.pem \
+  --embed-certs=true \
+  --server=https://${KUBERNETES_PUBLIC_ADDRESS}:6443 \
+  --kubeconfig=kube-proxy.kubeconfig
+```
+
+```
+kubectl config set-credentials kube-proxy \
+  --client-certificate=kube-proxy.pem \
+  --client-key=kube-proxy-key.pem \
+  --embed-certs=true \
+  --kubeconfig=kube-proxy.kubeconfig
+```
+
+```
+kubectl config set-context default \
+  --cluster=kubernetes-the-hard-way \
+  --user=kube-proxy \
+  --kubeconfig=kube-proxy.kubeconfig
+```
+
+```
+kubectl config use-context default --kubeconfig=kube-proxy.kubeconfig
+```
+
+## Distribute the Kubernetes Configuration Files
+
+Copy the appropriate `kubelet` and `kube-proxy` kubeconfig files to each worker instance:
+
+```
+for instance in worker-0 worker-1 worker-2; do
+  gcloud compute scp ${instance}.kubeconfig kube-proxy.kubeconfig ${instance}:~/
+done
+```
+
+Next: [Generating the Data Encryption Config and Key](06-data-encryption-keys.md)