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docs/12-dns-addon.md

@@ -6,13 +6,13 @@ In this lab you will deploy the [DNS add-on](https://kubernetes.io/docs/concepts
 
 Deploy the `coredns` cluster add-on:
 
-```
+```bash
 kubectl apply -f https://storage.googleapis.com/kubernetes-the-hard-way/coredns.yaml
 ```
 
 > output
 
-```
+```bash
 serviceaccount/coredns created
 clusterrole.rbac.authorization.k8s.io/system:coredns created
 clusterrolebinding.rbac.authorization.k8s.io/system:coredns created
@@ -23,13 +23,13 @@ service/kube-dns created
 
 List the pods created by the `kube-dns` deployment:
 
-```
+```bash
 kubectl get pods -l k8s-app=kube-dns -n kube-system
 ```
 
 > output
 
-```
+```bash
 NAME                       READY   STATUS    RESTARTS   AGE
 coredns-699f8ddd77-94qv9   1/1     Running   0          20s
 coredns-699f8ddd77-gtcgb   1/1     Running   0          20s
@@ -39,38 +39,38 @@ coredns-699f8ddd77-gtcgb   1/1     Running   0          20s
 
 Create a `busybox` deployment:
 
-```
+```bash
 kubectl run --generator=run-pod/v1 busybox --image=busybox:1.28 --command -- sleep 3600
 ```
 
 List the pod created by the `busybox` deployment:
 
-```
+```bash
 kubectl get pods -l run=busybox
 ```
 
 > output
 
-```
+```bash
 NAME      READY   STATUS    RESTARTS   AGE
 busybox   1/1     Running   0          3s
 ```
 
 Retrieve the full name of the `busybox` pod:
 
-```
+```bash
 POD_NAME=$(kubectl get pods -l run=busybox -o jsonpath="{.items[0].metadata.name}")
 ```
 
 Execute a DNS lookup for the `kubernetes` service inside the `busybox` pod:
 
-```
+```bash
 kubectl exec -ti $POD_NAME -- nslookup kubernetes
 ```
 
 > output
 
-```
+```bash
 Server:    10.32.0.10
 Address 1: 10.32.0.10 kube-dns.kube-system.svc.cluster.local