[en] update en docs to use recommended labels

content/en/docs/tasks/network/validate-dual-stack.md

@@ -134,7 +134,7 @@ spec:
     protocol: TCP
     targetPort: 9376
   selector:
-    app: MyApp
+    app.kubernetes.io/name: MyApp
   sessionAffinity: None
   type: ClusterIP
 status:
@@ -158,7 +158,7 @@ apiVersion: v1
 kind: Service
 metadata:
   labels:
-    app: MyApp
+    app.kubernetes.io/name: MyApp
   name: my-service
 spec:
   clusterIP: fd00::5118
@@ -172,7 +172,7 @@ spec:
     protocol: TCP
     targetPort: 80
   selector:
-    app: MyApp
+    app.kubernetes.io/name: MyApp
   sessionAffinity: None
   type: ClusterIP
 status:
@@ -187,7 +187,7 @@ Create the following Service that explicitly defines `PreferDualStack` in `.spec
 The `kubectl get svc` command will only show the primary IP in the `CLUSTER-IP` field.
 
 ```shell
-kubectl get svc -l app=MyApp
+kubectl get svc -l app.kubernetes.io/name=MyApp
 
 NAME         TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)   AGE
 my-service   ClusterIP   10.0.216.242   <none>        80/TCP    5s
@@ -197,15 +197,15 @@ my-service   ClusterIP   10.0.216.242   <none>        80/TCP    5s
 Validate that the Service gets cluster IPs from the IPv4 and IPv6 address blocks using `kubectl describe`. You may then validate access to the service via the IPs and ports.
 
 ```shell
-kubectl describe svc -l app=MyApp
+kubectl describe svc -l app.kubernetes.io/name=MyApp
 ```
 
 ```
 Name:              my-service
 Namespace:         default
-Labels:            app=MyApp
+Labels:            app.kubernetes.io/name=MyApp
 Annotations:       <none>
-Selector:          app=MyApp
+Selector:          app.kubernetes.io/name=MyApp
 Type:              ClusterIP
 IP Family Policy:  PreferDualStack
 IP Families:       IPv4,IPv6
@@ -220,14 +220,14 @@ Events:            <none>
 
 ### Create a dual-stack load balanced Service
 
-If the cloud provider supports the provisioning of IPv6 enabled external load balancers, create the following Service with `PreferDualStack` in `.spec.ipFamilyPolicy`, `IPv6` as the first element of the `.spec.ipFamilies` array and the `type` field set to `LoadBalancer`. 
+If the cloud provider supports the provisioning of IPv6 enabled external load balancers, create the following Service with `PreferDualStack` in `.spec.ipFamilyPolicy`, `IPv6` as the first element of the `.spec.ipFamilies` array and the `type` field set to `LoadBalancer`.
 
 {{< codenew file="service/networking/dual-stack-prefer-ipv6-lb-svc.yaml" >}}
 
 Check the Service:
 
 ```shell
-kubectl get svc -l app=MyApp
+kubectl get svc -l app.kubernetes.io/name=MyApp
 ```
 
 Validate that the Service receives a `CLUSTER-IP` address from the IPv6 address block along with an `EXTERNAL-IP`. You may then validate access to the service via the IP and port.