ingress: update edge ingress md

docs/user-manuals/network/edge-ingress.md

@@ -3,17 +3,20 @@ title: Edge Ingress
 ---
 
 This document introduces how to access Edge services through Edge Ingress in Cloud Edge scenarios.
+Users can access the Edge services from inside or outside of the NodePools, and for the condition
+from outside of the NodePools, only NodePort type ingress controller service is supported by now.
 
 Generally, it only needs 2 steps to use the Edge Ingress feature:
-1. Enable the ingress feature on NodePools which provide your desired services.
-2. Create and apply the ingress rule as K8S to access your desired services.
 
-Follow the details below to try the Edge Ingress feature:
+  1. Enable the ingress feature on NodePools which provide your desired services.
+  2. Create and apply the ingress rule as K8S to access your desired services.
+
+Follow the steps below to try the Edge Ingress feature:
 
 ---
 1.Enable the ingress feature on NodePools which provide your desired services
 ---
-YurtIngress operator is responsible for deploying the nginx ingress controller to the corresponding NodePools.
+YurtIngress operator is responsible for orchestrating multi ingress controllers to the corresponding NodePools.
 Suppose you have created 4 NodePools in your OpenYurt cluster: pool01, pool02, pool03, pool04, and you want to
 enable edge ingress feature on pool01 and pool03, you can create the YurtIngress CR as below:
 
@@ -37,67 +40,133 @@ b). In spec, the "ingress_controller_replicas_per_pool" represents the ingress c
 It is used for the HA usage scenarios.
 
 c). In spec, the "pools" represents the pools list on which you want to enable ingress feature.
-Currently it only supports the pool name, but it can be extended to support pool personalized configruations in future.
+Currently it only supports the pool name, and it can be extended to support pool personalized configurations in future.
 
 
 2). Apply the YurtIngress CR yaml file
 
-    kubectl apply -f yurtingress-test.yaml
+    #kubectl apply -f yurtingress-test.yaml
     yurtingress.apps.openyurt.io/yurtingress-singleton created
 
 Then you can get the YurtIngress CR to check the status:
 
-    kubectl get ying
+    #kubectl get ying
     NAME                    NGINX-INGRESS-VERSION   REPLICAS-PER-POOL   READYNUM   NOTREADYNUM   AGE
     yurtingress-singleton   0.48.1                  1                   2          0             3m13s
 
 When the ingress controller is enabled successfully, a per-pool NodePort service is created to expose the ingress controller serivce:
 
-    kubectl get svc -A
+    #kubectl get svc -n ingress-nginx
     ingress-nginx   pool01-ingress-nginx-controller   NodePort    192.167.107.123   <none>    80:32255/TCP,443:32275/TCP   53m
     ingress-nginx   pool03-ingress-nginx-controller   NodePort    192.167.48.114    <none>    80:30531/TCP,443:30916/TCP   53m
 
 Notes:
 
 a). "ying" is the shortName of YurtIngress resource.
 
-b). Currently YurtIngress only supports the fixed nginx ingress controller version, we will enhance it in future to support user configurable
-nginx ingress controller images/versions.
+b). Currently YurtIngress only supports the fixed nginx ingress controller version, it can be enhanced to support user configurable
+nginx ingress controller images/versions in future.
+
+c). When the "READYNUM" equals the pools number you defined in the YurtIngress CR, it represents the ingress feature is ready on all your spec pools.
 
-c). When the "READYNUM" equals the pool number you defined in the YurtIngress CR, it represents the ingress feature is ready on all the pool you defined.
+d). If the "NOTREADYNUM" is not 0 all the times, you can check the YurtIngress CR for the the status infomation.
+Also you can check the corresponding deployments and pods to figure out why the ingress is not ready yet.
 
-d). If the "NOTREADYNUM" is not 0 all the times, you can use "kubectl describe ying yurtingress-singleton" to check the details for the reasons.
-Also you can check the corresponding deployment (xxx-ingress-nginx-controller, "xxx" represents the pool name) to figure out the reasons why the
-ingress is not ready yet.
+e). For every NodePool which ingress is enabled successfully, it exposes a NodePort type service for users to access the nginx ingress controller.
 
-e). For every NodePool which ingress is enable successfully, it exposes a NodePort type service for users to access the nginx ingress controller.
+f). When the ingress controllers are orchestrated to the specified NodePools, an "ingress-nginx" namespace will be created, and all the namespace
+related resources will be created under it.
 
 ---
 2.Create and apply the ingress rule as K8S to access your desired services
 ---
 When the step 1 above is done, you have successfully deployed the nginx ingress controller to the related NodePools, and the following
 ingress user experience is totally consistent with K8S.
 
-Suppose your app workload is deployed to several NodePools(e.g. pool01 and pool03), and it exposes a global service(e.g. myapp service), and you
-want to access the service provided by pool01:
+Suppose your app workload is deployed to several NodePools and it exposes a global service, for example:
+
+      apiVersion: apps/v1
+      kind: Deployment
+      metadata:
+        name: pool01-deployment
+        labels:
+          app: echo
+      spec:
+        replicas: 2
+        selector:
+          matchLabels:
+            app: echo
+        template:
+          metadata:
+            labels:
+              app: echo
+          spec:
+            containers:
+            - name: echo-app
+              image: hashicorp/http-echo
+              args:
+                - "-text=echo from nodepool pool01"
+              imagePullPolicy: IfNotPresent
+            nodeSelector:
+              apps.openyurt.io/nodepool: pool01
+      ---
+
+      apiVersion: apps/v1
+      kind: Deployment
+      metadata:
+        name: pool03-deployment
+        labels:
+          app: echo
+      spec:
+        replicas: 2
+        selector:
+          matchLabels:
+            app: echo
+        template:
+          metadata:
+            labels:
+              app: echo
+          spec:
+            containers:
+            - name: echo-app
+              image: hashicorp/http-echo
+              args:
+                - "-text=echo from nodepool pool03"
+              imagePullPolicy: IfNotPresent
+            nodeSelector:
+              apps.openyurt.io/nodepool: pool03
+      ---
+
+      kind: Service
+      apiVersion: v1
+      metadata:
+        name: echo-service
+      spec:
+        selector:
+          app: echo
+        ports:
+          - port: 5678
+
+
+If you want to access the service provided by pool01:
 
 1). Create the ingress rule yaml file: (for example: ingress-myapp.yaml)
 
-    apiVersion: extensions/v1beta1
-    kind: Ingress
-    metadata:
-      name: ingress-myapp
-      annotations:
-        ingress.kubernetes.io/rewrite-target: /
-    spec:
-      ingressclassName: pool01
-      rules:
-      - http:
-          paths:
-            - path: /myapp
-              backend:
-              serviceName: myapp-service
-              servicePort: xxx
+      apiVersion: extensions/v1beta1
+      kind: Ingress
+      metadata:
+        name: ingress-pool01
+        annotations:
+          kubernetes.io/ingress.class: pool01
+          ingress.kubernetes.io/rewrite-target: /
+      spec:
+        rules:
+        - http:
+            paths:
+              - path: /echo
+                backend:
+                  serviceName: echo-service
+                  servicePort: 5678
 
 Notes:
 
@@ -108,14 +177,16 @@ b). The ingress CR definition may be different for different K8S versions, so yo
 
 2). Apply the ingress rule yaml file:
 
-      kubectl apply -f ingress-myapp.yaml
+      #kubectl apply -f ingress-myapp.yaml
       ingress.extensions/ingress-myapp created
 
 
 
 After all the steps above are done successfully, you can verify the edge ingress feature through the ingress controller NodePort service:
 
-      curl xxx:32255/myapp
+      #curl xxx:32255/echo
 
       "xxx" 	represents any NodeIP in NodePool pool01
       "32255" 	represents the NodePort which pool01 nginx ingress controller service exposes
+
+      It should return "echo from nodepool pool01" all the times.