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docs/13-smoke-test.md

@@ -8,14 +8,14 @@ In this section you will verify the ability to [encrypt secret data at rest](htt
 
 Create a generic secret:
 
-```
+```bash
 kubectl create secret generic kubernetes-the-hard-way \
   --from-literal="mykey=mydata"
 ```
 
 Print a hexdump of the `kubernetes-the-hard-way` secret stored in etcd:
 
-```
+```bash
 gcloud compute ssh controller-0 \
   --command "sudo ETCDCTL_API=3 etcdctl get \
   --endpoints=https://127.0.0.1:2379 \
@@ -27,7 +27,7 @@ gcloud compute ssh controller-0 \
 
 > output
 
-```
+```bash
 00000000  2f 72 65 67 69 73 74 72  79 2f 73 65 63 72 65 74  |/registry/secret|
 00000010  73 2f 64 65 66 61 75 6c  74 2f 6b 75 62 65 72 6e  |s/default/kubern|
 00000020  65 74 65 73 2d 74 68 65  2d 68 61 72 64 2d 77 61  |etes-the-hard-wa|
@@ -53,19 +53,19 @@ In this section you will verify the ability to create and manage [Deployments](h
 
 Create a deployment for the [nginx](https://nginx.org/en/) web server:
 
-```
+```bash
 kubectl create deployment nginx --image=nginx
 ```
 
 List the pod created by the `nginx` deployment:
 
-```
+```bash
 kubectl get pods -l app=nginx
 ```
 
 > output
 
-```
+```bash
 NAME                     READY   STATUS    RESTARTS   AGE
 nginx-554b9c67f9-vt5rn   1/1     Running   0          10s
 ```
@@ -76,32 +76,32 @@ In this section you will verify the ability to access applications remotely usin
 
 Retrieve the full name of the `nginx` pod:
 
-```
+```bash
 POD_NAME=$(kubectl get pods -l app=nginx -o jsonpath="{.items[0].metadata.name}")
 ```
 
 Forward port `8080` on your local machine to port `80` of the `nginx` pod:
 
-```
+```bash
 kubectl port-forward $POD_NAME 8080:80
 ```
 
 > output
 
-```
+```bash
 Forwarding from 127.0.0.1:8080 -> 80
 Forwarding from [::1]:8080 -> 80
 ```
 
 In a new terminal make an HTTP request using the forwarding address:
 
-```
+```bash
 curl --head http://127.0.0.1:8080
 ```
 
 > output
 
-```
+```bash
 HTTP/1.1 200 OK
 Server: nginx/1.17.3
 Date: Sat, 14 Sep 2019 21:10:11 GMT
@@ -115,7 +115,7 @@ Accept-Ranges: bytes
 
 Switch back to the previous terminal and stop the port forwarding to the `nginx` pod:
 
-```
+```bash
 Forwarding from 127.0.0.1:8080 -> 80
 Forwarding from [::1]:8080 -> 80
 Handling connection for 8080
@@ -128,13 +128,13 @@ In this section you will verify the ability to [retrieve container logs](https:/
 
 Print the `nginx` pod logs:
 
-```
+```bash
 kubectl logs $POD_NAME
 ```
 
 > output
 
-```
+```bash
 127.0.0.1 - - [14/Sep/2019:21:10:11 +0000] "HEAD / HTTP/1.1" 200 0 "-" "curl/7.52.1" "-"
 ```
 
@@ -144,13 +144,13 @@ In this section you will verify the ability to [execute commands in a container]
 
 Print the nginx version by executing the `nginx -v` command in the `nginx` container:
 
-```
+```bash
 kubectl exec -ti $POD_NAME -- nginx -v
 ```
 
 > output
 
-```
+```bash
 nginx version: nginx/1.17.3
 ```
 
@@ -160,7 +160,7 @@ In this section you will verify the ability to expose applications using a [Serv
 
 Expose the `nginx` deployment using a [NodePort](https://kubernetes.io/docs/concepts/services-networking/service/#type-nodeport) service:
 
-```
+```bash
 kubectl expose deployment nginx --port 80 --type NodePort
 ```
 
@@ -168,14 +168,14 @@ kubectl expose deployment nginx --port 80 --type NodePort
 
 Retrieve the node port assigned to the `nginx` service:
 
-```
+```bash
 NODE_PORT=$(kubectl get svc nginx \
   --output=jsonpath='{range .spec.ports[0]}{.nodePort}')
 ```
 
 Create a firewall rule that allows remote access to the `nginx` node port:
 
-```
+```bash
 gcloud compute firewall-rules create kubernetes-the-hard-way-allow-nginx-service \
   --allow=tcp:${NODE_PORT} \
   --network kubernetes-the-hard-way
@@ -183,20 +183,20 @@ gcloud compute firewall-rules create kubernetes-the-hard-way-allow-nginx-service
 
 Retrieve the external IP address of a worker instance:
 
-```
+```bash
 EXTERNAL_IP=$(gcloud compute instances describe worker-0 \
   --format 'value(networkInterfaces[0].accessConfigs[0].natIP)')
 ```
 
 Make an HTTP request using the external IP address and the `nginx` node port:
 
-```
+```bash
 curl -I http://${EXTERNAL_IP}:${NODE_PORT}
 ```
 
 > output
 
-```
+```bash
 HTTP/1.1 200 OK
 Server: nginx/1.17.3
 Date: Sat, 14 Sep 2019 21:12:35 GMT