Update configure-namespace-isolation.md (#3758)

* Update configure-namespace-isolation.md

* Update configure-namespace-isolation.md

docs/tasks/administer-cluster/configure-namespace-isolation.md

@@ -5,14 +5,15 @@ assignees:
 - danwinship
 title: Configuring Namespace Isolation
 ---
+{% capture overview %}
+This page shows how to add `NetworkPolicy` objects to an isolated namespace to specify what traffic should be allowed.
+{% endcapture %}
 
-* TOC
-{:toc}
-
-## Prerequisites
-
+{% capture prerequisites %}
 Network policies are implemented by the network plugin, so you must be using a networking solution which supports `NetworkPolicy` - simply creating the resource without a controller to implement it will have no effect.
+{% endcapture %}
 
+{% capture steps %}
 ## Configuring Namespace Isolation
 
 By default, all traffic is allowed between all pods (and `NetworkPolicy` resources have no effect).
@@ -42,49 +43,9 @@ NOTE: older network plugins may instead require the v1beta1 syntax, using an ann
 kubectl annotate ns <namespace> "net.beta.kubernetes.io/network-policy={\"ingress\": {\"isolation\": \"DefaultDeny\"}}"
 {% endraw %}
 ```
+{% endcapture %}
 
-## The `NetworkPolicy` Resource
-
-See the [api-reference](/docs/api-reference/networking/v1/definitions/#_v1_networkpolicy) for a full definition of the resource.
-
-An example `NetworkPolicy` might look like this:
-
-```yaml
-apiVersion: networking/v1
-kind: NetworkPolicy
-metadata:
-  name: test-network-policy
-  namespace: default
-spec:
-  podSelector:
-    matchLabels:
-      role: db
-  ingress:
-  - from:
-    - namespaceSelector:
-        matchLabels:
-          project: myproject
-    - podSelector:
-        matchLabels:
-          role: frontend
-    ports:
-    - protocol: tcp
-      port: 6379
-```
-
-*POSTing this to the API server will have no effect unless your chosen networking solution supports network policy.*
-
-__Mandatory Fields__: As with all other Kubernetes config, a `NetworkPolicy` needs `apiVersion`, `kind`, and `metadata` fields.  For general information about working with config files, see [here](/docs/user-guide/simple-yaml), [here](/docs/user-guide/configuring-containers), and [here](/docs/user-guide/working-with-resources).
-
-__spec__: `NetworkPolicy` [spec](https://github.com/kubernetes/kubernetes/tree/{{page.githubbranch}}/docs/devel/api-conventions.md#spec-and-status) has all the information needed to define a particular network policy in the given namespace.
-
-__podSelector__: Each `NetworkPolicy` includes a `podSelector` which selects the grouping of pods to which the `ingress` rules in the policy apply. The example policy selects pods with the label "role=db".
-
-__ingress__: Each `NetworkPolicy` includes a list of whitelist `ingress` rules.  Each rule allows traffic which matches both the `from` and `ports` sections. The example policy contains a single rule, which matches traffic on a single port, from either of two sources, the first specified via a `namespaceSelector` and the second specified via a `podSelector`.
-
-So, the example NetworkPolicy:
-
-1. allows connections to tcp port 6379 of "role=db" pods in the "default" namespace from any pod in the "default" namespace with the label "role=frontend"
-2. allows connections to tcp port 6379 of "role=db" pods in the "default" namespace from any pod in a namespace with the label "project=myproject"
-
-See the [NetworkPolicy getting started guide](/docs/getting-started-guides/network-policy/walkthrough) for further examples.
+{% capture whatsnext %}
+* For conceptual information about Network Policies, see [Network Policies](/docs/concepts/services-networking/networkpolicies).
+{% endcapture %}
+{% include templates/task.md %}