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Ingress

• Take me to Lecture

In this section, we will take a look at Ingress

• Ingress Controller
• Ingress Resources

Ingress Controller

• Deployment of Ingress Controller

ConfigMap

kind: ConfigMap
apiVersion: v1
metadata:
  name: nginx-configuration

Deployment

apiVersion: apps/v1
kind: Deployment
metadata:
  name: ingress-controller
spec:
  replicas: 1
  selector:
    matchLabels:
      name: nginx-ingress
  template:
    metadata:
      labels:
        name: nginx-ingress
    spec:
      serviceAccountName: ingress-serviceaccount
      containers:
        - name: nginx-ingress-controller
          image: quay.io/kubernetes-ingress-controller/nginx-ingress-controller:0.21.0
          args:
            - /nginx-ingress-controller
            - --configmap=$(POD_NAMESPACE)/nginx-configuration
          env:
            - name: POD_NAME
              valueFrom:
                fieldRef:
                  fieldPath: metadata.name
            - name: POD_NAMESPACE
              valueFrom:
                fieldRef:
                  fieldPath: metadata.namespace
          ports:
            - name: http
              containerPort: 80
            - name: https
              containerPort: 443

ServiceAccount

• ServiceAccount require for authentication purposes along with correct Roles, ClusterRoles and RoleBindings.

• Create a ingress service account

  $ kubectl create -f ingress-sa.yaml
  serviceaccount/ingress-serviceaccount created
  

Service Type - NodePort

# service-Nodeport.yaml

apiVersion: v1
kind: Service
metadata:
  name: ingress
spec:
  type: NodePort
  ports:
  - port: 80
    targetPort: 80
    protocol: TCP
    name: http
  - port: 443
    targetPort: 443
    protocol: TCP
    name: https
  selector:
    name: nginx-ingress

• Create a service

  $ kubectl create -f service-Nodeport.yaml
  

• To get the service

$ kubectl get service

Ingress Resources

Ingress-wear.yaml

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: ingress-wear
spec:
     backend:
        serviceName: wear-service
        servicePort: 80

• To create the ingress resource

  $ kubectl create -f Ingress-wear.yaml
  ingress.extensions/ingress-wear created
  

• To get the ingress

  $ kubectl get ingress
  NAME           CLASS    HOSTS   ADDRESS   PORTS   AGE
  ingress-wear   <none>   *                 80      18s
  

Ingress Resource - Rules

• 1 Rule and 2 Paths.

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: ingress-wear-watch
spec:
  rules:
  - http:
      paths:
      - path: /wear
        backend:
          serviceName: wear-service
          servicePort: 80
      - path: /watch
        backend:
          serviceName: watch-service
          servicePort: 80

• Describe the earlier created ingress resource

$ kubectl describe ingress ingress-wear-watch
Name:             ingress-wear-watch
Namespace:        default
Address:
Default backend:  default-http-backend:80 (<none>)
Rules:
  Host        Path  Backends
  ----        ----  --------
  *
              /wear    wear-service:80 (<none>)
              /watch   watch-service:80 (<none>)
Annotations:  <none>
Events:
  Type    Reason  Age   From                      Message
  ----    ------  ----  ----                      -------
  Normal  CREATE  23s   nginx-ingress-controller  Ingress default/ingress-wear-watch

• 2 Rules and 1 Path each. ```

  Ingress-wear-watch.yaml

apiVersion: extensions/v1beta1 kind: Ingress metadata: name: ingress-wear-watch spec: rules:

• host: wear.my-online-store.com http: paths:
  • backend: serviceName: wear-service servicePort: 80
• host: watch.my-online-store.com http: paths:
  • backend: serviceName: watch-service servicePort: 80 ```

References Docs

• https://kubernetes.io/docs/concepts/services-networking/ingress/
• https://kubernetes.io/docs/concepts/services-networking/ingress-controllers/
• https://thenewstack.io/kubernetes-ingress-for-beginners/