Tidy port forward task

* Reword to follow style guidelines

* Highlight commands as shell code

* Specify minimum version

This metadata alters the behavior of the {{< version-check >}}
shortcode.

* Downgrade warning to note

I don't see any adverse consequences if the reader is unaware that port
forwarding for UDP is not yet implemented.

content/en/docs/tasks/access-application-cluster/port-forward-access-application-cluster.md

@@ -2,6 +2,7 @@
 title: Use Port Forwarding to Access Applications in a Cluster
 content_template: templates/task
 weight: 40
+min-kubernetes-server-version: v1.10
 ---
 
 {{% capture overview %}}
@@ -26,104 +27,157 @@ for database debugging.
 
 ## Creating Redis deployment and service
 
-1. Create a Redis deployment:
+1. Create a Deployment that runs Redis:
 
+    ```shell
     kubectl apply -f https://k8s.io/examples/application/guestbook/redis-master-deployment.yaml
+    ```
 
     The output of a successful command verifies that the deployment was created:
 
+    ```
     deployment.apps/redis-master created
+    ```
 
     View the pod status to check that it is ready:
 
+    ```shell
     kubectl get pods
+    ```
 
     The output displays the pod created:
 
+    ```
     NAME                            READY     STATUS    RESTARTS   AGE
     redis-master-765d459796-258hz   1/1       Running   0          50s
+    ```
 
-    View the deployment status:
+    View the Deployment's status:
 
+    ```shell
     kubectl get deployment
+    ```
 
-    The output displays that the deployment was created:
+    The output displays that the Deployment was created:
 
+    ```
     NAME         READY   UP-TO-DATE   AVAILABLE   AGE
     redis-master 1/1     1            1           55s
+    ```
 
-    View the replicaset status using:
+    The Deployment automatically manages a ReplicaSet.
+    View the ReplicaSet status using:
 
-        kubectl get rs
+    ```shell
+    kubectl get replicaset
+    ```
 
-    The output displays that the replicaset was created:
+    The output displays that the ReplicaSet was created:
 
+    ```
     NAME                      DESIRED   CURRENT   READY     AGE
     redis-master-765d459796   1         1         1         1m
+    ```
 
 
-2. Create a Redis service:
+2. Create a Service to expose Redis on the network:
 
+    ```shell
     kubectl apply -f https://k8s.io/examples/application/guestbook/redis-master-service.yaml
+    ```
 
-    The output of a successful command verifies that the service was created:
+    The output of a successful command verifies that the Service was created:
 
+    ```
     service/redis-master created
+    ```
 
-    Check the service created:
+    Check the Service created:
 
-        kubectl get svc | grep redis
+    ```shell
+    kubectl get service redis-master
+    ```
 
     The output displays the service created:
 
+    ```
     NAME           TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)    AGE
     redis-master   ClusterIP   10.0.0.213   <none>        6379/TCP   27s
+    ```
 
-3. Verify that the Redis server is running in the pod and listening on port 6379:
+3. Verify that the Redis server is running in the Pod, and listening on port 6379:
 
-        kubectl get pods redis-master-765d459796-258hz --template='{{(index (index .spec.containers 0).ports 0).containerPort}}{{"\n"}}'
+    ```shell
+    # Change redis-master-765d459796-258hz to the name of the Pod
+    kubectl get pod redis-master-765d459796-258hz --template='{{(index (index .spec.containers 0).ports 0).containerPort}}{{"\n"}}'
+    ```
 
-    The output displays the port:
+    The output displays the port for Redis in that Pod:
 
+    ```
     6379
+    ```
+
+    (this is the TCP port allocated to Redis on the internet).
+
+## Forward a local port to a port on the Pod
+
+1.  `kubectl port-forward` allows using resource name, such as a pod name, to select a matching pod to port forward to.
 
 
-## Forward a local port to a port on the pod
+    ```shell
-
+    # Change redis-master-765d459796-258hz to the name of the Pod
-1.  `kubectl port-forward` allows using resource name, such as a pod name, to select a matching pod to port forward to since Kubernetes v1.10.
-
     kubectl port-forward redis-master-765d459796-258hz 7000:6379
+    ```
 
     which is the same as
 
+    ```shell
     kubectl port-forward pods/redis-master-765d459796-258hz 7000:6379
+    ```
 
     or
 
+    ```shell
     kubectl port-forward deployment/redis-master 7000:6379
+    ```
 
     or
 
-        kubectl port-forward rs/redis-master 7000:6379
+    ```shell
+    kubectl port-forward replicaset/redis-master 7000:6379
+    ```
 
     or
 
-        kubectl port-forward svc/redis-master 7000:6379
+    ```shell
+    kubectl port-forward service/redis-master 7000:6379
+    ```
 
     Any of the above commands works. The output is similar to this:
 
+    ```
     I0710 14:43:38.274550    3655 portforward.go:225] Forwarding from 127.0.0.1:7000 -> 6379
     I0710 14:43:38.274797    3655 portforward.go:225] Forwarding from [::1]:7000 -> 6379
+    ```
 
 2.  Start the Redis command line interface:
 
+    ```shell
     redis-cli -p 7000
+    ```
 
 3.  At the Redis command line prompt, enter the `ping` command:
 
-        127.0.0.1:7000>ping
+    ```
+    ping
+    ```
 
-    A successful ping request returns PONG.
+    A successful ping request returns:
+
+    ```
+    PONG
+    ```
 
 {{% /capture %}}
 
@@ -132,15 +186,15 @@ for database debugging.
 
 ## Discussion
 
-Connections made to local port 7000 are forwarded to port 6379 of the pod that
+Connections made to local port 7000 are forwarded to port 6379 of the Pod that
-is running the Redis server. With this connection in place you can use your
+is running the Redis server. With this connection in place, you can use your
-local workstation to debug the database that is running in the pod.
+local workstation to debug the database that is running in the Pod.
 
-{{< warning >}}
+{{< note >}}
-Due to known limitations, port forward today only works for TCP protocol.
+`kubectl port-forward` is implemented for TCP ports only.
-The support to UDP protocol is being tracked in
+The support for UDP protocol is tracked in
 [issue 47862](https://github.com/kubernetes/kubernetes/issues/47862).
-{{< /warning >}}
+{{< /note >}}
 
 {{% /capture %}}
 
@@ -148,6 +202,3 @@ The support to UDP protocol is being tracked in
 {{% capture whatsnext %}}
 Learn more about [kubectl port-forward](/docs/reference/generated/kubectl/kubectl-commands/#port-forward).
 {{% /capture %}}
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-
-