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docs/08-bootstrapping-kubernetes-controllers.md

@@ -6,7 +6,7 @@ In this lab you will bootstrap the Kubernetes control plane across three compute
 
 The commands in this lab must be run on each controller instance: `controller-0`, `controller-1`, and `controller-2`. Login to each controller instance using the `gcloud` command. Example:
 
-```
+```bash
 gcloud compute ssh controller-0
 ```
 
@@ -18,7 +18,7 @@ gcloud compute ssh controller-0
 
 Create the Kubernetes configuration directory:
 
-```
+```bash
 sudo mkdir -p /etc/kubernetes/config
 ```
 
@@ -26,7 +26,7 @@ sudo mkdir -p /etc/kubernetes/config
 
 Download the official Kubernetes release binaries:
 
-```
+```bash
 wget -q --show-progress --https-only --timestamping \
   "https://storage.googleapis.com/kubernetes-release/release/v1.15.3/bin/linux/amd64/kube-apiserver" \
   "https://storage.googleapis.com/kubernetes-release/release/v1.15.3/bin/linux/amd64/kube-controller-manager" \
@@ -36,7 +36,7 @@ wget -q --show-progress --https-only --timestamping \
 
 Install the Kubernetes binaries:
 
-```
+```bash
 {
   chmod +x kube-apiserver kube-controller-manager kube-scheduler kubectl
   sudo mv kube-apiserver kube-controller-manager kube-scheduler kubectl /usr/local/bin/
@@ -45,7 +45,7 @@ Install the Kubernetes binaries:
 
 ### Configure the Kubernetes API Server
 
-```
+```bash
 {
   sudo mkdir -p /var/lib/kubernetes/
 
@@ -57,14 +57,14 @@ Install the Kubernetes binaries:
 
 The instance internal IP address will be used to advertise the API Server to members of the cluster. Retrieve the internal IP address for the current compute instance:
 
-```
+```bash
 INTERNAL_IP=$(curl -s -H "Metadata-Flavor: Google" \
   http://metadata.google.internal/computeMetadata/v1/instance/network-interfaces/0/ip)
 ```
 
 Create the `kube-apiserver.service` systemd unit file:
 
-```
+```bash
 cat <<EOF | sudo tee /etc/systemd/system/kube-apiserver.service
 [Unit]
 Description=Kubernetes API Server
@@ -112,13 +112,13 @@ EOF
 
 Move the `kube-controller-manager` kubeconfig into place:
 
-```
+```bash
 sudo mv kube-controller-manager.kubeconfig /var/lib/kubernetes/
 ```
 
 Create the `kube-controller-manager.service` systemd unit file:
 
-```
+```bash
 cat <<EOF | sudo tee /etc/systemd/system/kube-controller-manager.service
 [Unit]
 Description=Kubernetes Controller Manager
@@ -150,13 +150,13 @@ EOF
 
 Move the `kube-scheduler` kubeconfig into place:
 
-```
+```bash
 sudo mv kube-scheduler.kubeconfig /var/lib/kubernetes/
 ```
 
 Create the `kube-scheduler.yaml` configuration file:
 
-```
+```bash
 cat <<EOF | sudo tee /etc/kubernetes/config/kube-scheduler.yaml
 apiVersion: kubescheduler.config.k8s.io/v1alpha1
 kind: KubeSchedulerConfiguration
@@ -169,7 +169,7 @@ EOF
 
 Create the `kube-scheduler.service` systemd unit file:
 
-```
+```bash
 cat <<EOF | sudo tee /etc/systemd/system/kube-scheduler.service
 [Unit]
 Description=Kubernetes Scheduler
@@ -189,7 +189,7 @@ EOF
 
 ### Start the Controller Services
 
-```
+```bash
 {
   sudo systemctl daemon-reload
   sudo systemctl enable kube-apiserver kube-controller-manager kube-scheduler
@@ -207,12 +207,12 @@ A [Google Network Load Balancer](https://cloud.google.com/compute/docs/load-bala
 
 Install a basic web server to handle HTTP health checks:
 
-```
+```bash
 sudo apt-get update
 sudo apt-get install -y nginx
 ```
 
-```
+```bash
 cat > kubernetes.default.svc.cluster.local <<EOF
 server {
   listen      80;
@@ -226,7 +226,7 @@ server {
 EOF
 ```
 
-```
+```bash
 {
   sudo mv kubernetes.default.svc.cluster.local \
     /etc/nginx/sites-available/kubernetes.default.svc.cluster.local
@@ -235,21 +235,21 @@ EOF
 }
 ```
 
-```
+```bash
 sudo systemctl restart nginx
 ```
 
-```
+```bash
 sudo systemctl enable nginx
 ```
 
 ### Verification
 
-```
+```bash
 kubectl get componentstatuses --kubeconfig admin.kubeconfig
 ```
 
-```
+```bash
 NAME                 STATUS    MESSAGE              ERROR
 controller-manager   Healthy   ok
 scheduler            Healthy   ok
@@ -260,11 +260,11 @@ etcd-1               Healthy   {"health": "true"}
 
 Test the nginx HTTP health check proxy:
 
-```
+```bash
 curl -H "Host: kubernetes.default.svc.cluster.local" -i http://127.0.0.1/healthz
 ```
 
-```
+```bash
 HTTP/1.1 200 OK
 Server: nginx/1.14.0 (Ubuntu)
 Date: Sat, 14 Sep 2019 18:34:11 GMT
@@ -286,13 +286,13 @@ In this section you will configure RBAC permissions to allow the Kubernetes API
 
 The commands in this section will effect the entire cluster and only need to be run once from one of the controller nodes.
 
-```
+```bash
 gcloud compute ssh controller-0
 ```
 
 Create the `system:kube-apiserver-to-kubelet` [ClusterRole](https://kubernetes.io/docs/admin/authorization/rbac/#role-and-clusterrole) with permissions to access the Kubelet API and perform most common tasks associated with managing pods:
 
-```
+```bash
 cat <<EOF | kubectl apply --kubeconfig admin.kubeconfig -f -
 apiVersion: rbac.authorization.k8s.io/v1beta1
 kind: ClusterRole
@@ -320,7 +320,7 @@ The Kubernetes API Server authenticates to the Kubelet as the `kubernetes` user
 
 Bind the `system:kube-apiserver-to-kubelet` ClusterRole to the `kubernetes` user:
 
-```
+```bash
 cat <<EOF | kubectl apply --kubeconfig admin.kubeconfig -f -
 apiVersion: rbac.authorization.k8s.io/v1beta1
 kind: ClusterRoleBinding
@@ -344,12 +344,11 @@ In this section you will provision an external load balancer to front the Kubern
 
 > The compute instances created in this tutorial will not have permission to complete this section. **Run the following commands from the same machine used to create the compute instances**.
 
-
 ### Provision a Network Load Balancer
 
 Create the external load balancer network resources:
 
-```
+```bash
 {
   KUBERNETES_PUBLIC_ADDRESS=$(gcloud compute addresses describe kubernetes-the-hard-way \
     --region $(gcloud config get-value compute/region) \
@@ -379,13 +378,13 @@ Create the external load balancer network resources:
 }
 ```
 
-### Verification
+### LB Verification
 
 > The compute instances created in this tutorial will not have permission to complete this section. **Run the following commands from the same machine used to create the compute instances**.
 
 Retrieve the `kubernetes-the-hard-way` static IP address:
 
-```
+```bash
 KUBERNETES_PUBLIC_ADDRESS=$(gcloud compute addresses describe kubernetes-the-hard-way \
   --region $(gcloud config get-value compute/region) \
   --format 'value(address)')
@@ -393,13 +392,13 @@ KUBERNETES_PUBLIC_ADDRESS=$(gcloud compute addresses describe kubernetes-the-har
 
 Make a HTTP request for the Kubernetes version info:
 
-```
+```bash
 curl --cacert ca.pem https://${KUBERNETES_PUBLIC_ADDRESS}:6443/version
 ```
 
 > output
 
-```
+```bash
 {
   "major": "1",
   "minor": "15",