Practice Test - CKA - Ingress Networking - 2

ㅁ We have deployed two applications. Explore the setup.

$ kubectl get all --all-namespaces
NAMESPACE     NAME                                       READY   STATUS    RESTARTS   AGE
app-space     pod/default-backend-5cf9bfb9d-t777q        1/1     Running   0          42s
app-space     pod/webapp-video-84f8655bd8-t75tl          1/1     Running   0          42s
app-space     pod/webapp-wear-6ff9445955-c47lj           1/1     Running   0          41s
kube-system   pod/coredns-f9fd979d6-9bc25                1/1     Running   0          119s
kube-system   pod/coredns-f9fd979d6-s2g8d                1/1     Running   0          119s
kube-system   pod/etcd-controlplane                      1/1     Running   0          2m8s
kube-system   pod/kube-apiserver-controlplane            1/1     Running   0          2m8s
kube-system   pod/kube-controller-manager-controlplane   1/1     Running   0          2m8s
kube-system   pod/kube-flannel-ds-amd64-h9ff9            1/1     Running   0          119s
kube-system   pod/kube-flannel-ds-amd64-hdvm4            1/1     Running   1          109s
kube-system   pod/kube-proxy-gc9qn                       1/1     Running   1          109s
kube-system   pod/kube-proxy-w2gz7                       1/1     Running   0          119s
kube-system   pod/kube-scheduler-controlplane            1/1     Running   0          2m8s

NAMESPACE     NAME                           TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)                  AGE
app-space     service/default-http-backend   ClusterIP   10.99.106.155   <none>        80/TCP                   42s
app-space     service/video-service          ClusterIP   10.107.155.36   <none>        8080/TCP                 42s
app-space     service/wear-service           ClusterIP   10.101.48.254   <none>        8080/TCP                 42s
default       service/kubernetes             ClusterIP   10.96.0.1       <none>        443/TCP                  2m17s
kube-system   service/kube-dns               ClusterIP   10.96.0.10      <none>        53/UDP,53/TCP,9153/TCP   2m15s

NAMESPACE     NAME                                     DESIRED   CURRENT   READY   UP-TO-DATE   AVAILABLE   NODE SELECTOR            AGE
kube-system   daemonset.apps/kube-flannel-ds-amd64     2         2         2       2            2           <none>                   2m11s
kube-system   daemonset.apps/kube-flannel-ds-arm       0         0         0       0            0           <none>                   2m11s
kube-system   daemonset.apps/kube-flannel-ds-arm64     0         0         0       0            0           <none>                   2m11s
kube-system   daemonset.apps/kube-flannel-ds-ppc64le   0         0         0       0            0           <none>                   2m11s
kube-system   daemonset.apps/kube-flannel-ds-s390x     0         0         0       0            0           <none>                   2m11s
kube-system   daemonset.apps/kube-proxy                2         2         2       2            2           kubernetes.io/os=linux   2m15s

NAMESPACE     NAME                              READY   UP-TO-DATE   AVAILABLE   AGE
app-space     deployment.apps/default-backend   1/1     1            1           42s
app-space     deployment.apps/webapp-video      1/1     1            1           42s
app-space     deployment.apps/webapp-wear       1/1     1            1           42s
kube-system   deployment.apps/coredns           2/2     2            2           2m15s

NAMESPACE     NAME                                        DESIRED   CURRENT   READY   AGE
app-space     replicaset.apps/default-backend-5cf9bfb9d   1         1         1       42s
app-space     replicaset.apps/webapp-video-84f8655bd8     1         1         1       42s
app-space     replicaset.apps/webapp-wear-6ff9445955      1         1         1       42s
kube-system   replicaset.apps/coredns-f9fd979d6           2         2         2       119s

 

ㅁ Let us now deploy an Ingress Controller. 

  First, create a namespace called 'ingress-space'

kubectl create namespace ingress-space

- Name: ingress-space

 

ㅁ The NGINX Ingress Controller requires a ConfigMap object. Create a ConfigMap object in the ingress-space

use the given spec on the right. No data needs to be configured in the ConfigMap

- Name: ingress-configuration

 

$ kubectl create configmap nginx-configuration -n ingress-space

configmap/nginx-configuration created

 

ㅁ The NGINX Ingress Controller requires a ServiceAccount. Create a ServiceAccount in the ingress-space.

- Name: ingress-serviceaccount

 

$ kubectl create serviceaccount ingress-serviceaccount -n ingress-space
serviceaccount/ingress-serviceaccount created

 

ㅁ We have created the Roles and RoleBinding for the ServiceAccount. Check it out.

kubectl get role,rolebindings --namespace ingress-space

NAME                                          CREATED AT
role.rbac.authorization.k8s.io/ingress-role   2021-03-31T14:08:49Z

NAME                                                         ROLE                AGE
rolebinding.rbac.authorization.k8s.io/ingress-role-binding   Role/ingress-role   65s

 

ㅁ Let us now deploy the Ingress Controller. Create a deployment using the file given

The deployment configuration is given at /root/ingress-controller.yaml. There are several issues with it. Try to fix them.

- Deployed in the correct namespace

- Replicas: 1

- Use the  right image

 

---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: ingress-controller
  namespace: ingress-space
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
            - --default-backend-service=app-space/default-http-backend
          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

ㅁ Let us now create a service to make Ingress available to external users.

create a service following the given specs.

- Name: ingress

- Type: NodePort

- Port: 80

- TargetPort: 80

- NodePort: 30080

- Use the right selector

 

---
apiVersion: v1
kind: Service
metadata:
  name: ingress
  namespace: ingress-space
spec:
  type: NodePort
  ports:
  - port: 80
    targetPort: 80
    protocol: TCP
    nodePort: 30080
    name: http
  - port: 443
    targetPort: 443
    protocol: TCP
    name: https
  selector:
    name: nginx-ingress
~                        

selector는 service가 바라보는 것이 Deployment 이므로 ingress-controller의 label을 확인하여 정의

 

 

ㅁ Create the ingress resource to make the appplication available at /wear and /watch on the Ingress Service

• Ingress Created
• Path: /wear
• Path: /watch
• Configure correct backend service for /wear
• Configure correct backend service for /watch
• Configure correct backend port for /wear service
• Configure correct backend port for /watch service

모법 답안

---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: ingress-wear-watch
  namespace: app-space
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /
    nginx.ingress.kubernetes.io/ssl-redirect: "false"
spec:
  rules:
  - http:
      paths:
      - path: /wear
        backend:
          serviceName: wear-service
          servicePort: 8080
      - path: /watch
        backend:
          serviceName: video-service
          servicePort: 8080

내가 한거

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: ingress
  namespace: app-space
spec:
  rules:
  - http:
      paths:
      - path: /wear
        pathType: ImplementationSpecific
        backend:
          service:
            name: wear-service
            port:
              number: 8080
  - http:
      paths:
      - path: /watch
        pathType: ImplementationSpecific
        backend:
          service:
            name: video-service
            port:
              number: 8080