kubernetes version is 1.16.0

Deploying tomcat

Deploy Tomcat but only allow intranet access. We need to route to Tomcat through the reverse proxy function provided by Ingress

apiVersion: apps/v1
kind: Deployment
metadata:
  name: tomcat-app
spec:
  selector:
    matchLabels:
      app: tomcat
  replicas: 2
  template:
    metadata:
      labels:
        app: tomcat
    spec:
      containers:
      - name: tomcat
        image: tomcat:8.5.47
        ports:
        # Default port for container
        - containerPort: 8080


---
apiVersion: v1
kind: Service
metadata:
  name: tomcat-http
spec:
  ports:
      # Port of service
    - port: 8081
      # Container default port, that is, mapping servcie8081 to pods8080
      targetPort: 8080
  # ClusterIP, NodePort, LoadBalancer
  type: ClusterIP
  selector:
    app: tomcat

Install nginx Progress Controller

There are many kinds of Ingress Controller. We choose the most familiar Nginx to process the request. Others can refer to

• Official documents
• Nginx progress controller configuration file

mkdir -p /usr/local/kubernetes/yaml/ingress
cd /usr/local/kubernetes/yaml/ingress

# Download profile
wget https://raw.githubusercontent.com/kubernetes/ingress-nginx/nginx-0.27.1/deploy/static/mandatory.yaml

Modify the configuration file vim mandatory.yaml, find the following configuration location (search serviceAccountName), and add a sentence hostNetwork: true

191 kind: Deployment
192 metadata:
193   name: nginx-ingress-controller
194   namespace: ingress-nginx
195   labels:
196     app.kubernetes.io/name: ingress-nginx
197     app.kubernetes.io/part-of: ingress-nginx
198 spec:
199   replicas: 1 # Set up to multiple. For example, 3
200   selector:
201     matchLabels:
202       app.kubernetes.io/name: ingress-nginx
203       app.kubernetes.io/part-of: ingress-nginx
204   template:
205     metadata:
206       labels:
207         app.kubernetes.io/name: ingress-nginx
208         app.kubernetes.io/part-of: ingress-nginx
209       annotations:
210         prometheus.io/port: "10254"
211         prometheus.io/scrape: "true"
212     spec:
213       # wait up to five minutes for the drain of connections
214       terminationGracePeriodSeconds: 300
215       serviceAccountName: nginx-ingress-serviceaccount
		 # Add hostNetwork: true, which means to open the host network mode and expose the Nginx service port 80
216       hostNetwork: true
217       nodeSelector:
218         kubernetes.io/os: linux
219       containers:
220         - name: nginx-ingress-controller
221           image: quay.io/kubernetes-ingress-controller/nginx-ingress-controller:master
222           args:
223             - /nginx-ingress-controller
224             - --configmap=$(POD_NAMESPACE)/nginx-configuration
225             - --tcp-services-configmap=$(POD_NAMESPACE)/tcp-services
226             - --udp-services-configmap=$(POD_NAMESPACE)/udp-services
227             - --publish-service=$(POD_NAMESPACE)/ingress-nginx
228             - --annotations-prefix=nginx.ingress.kubernetes.io
				'''''''''

Deploy ingress (Gateway)

cd /usr/local/kubernetes/yaml/ingress
vim ingress.yml

apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
  name: nginx-web
  annotations:
    # Specify the type of Ingress Controller
    kubernetes.io/ingress.class: "nginx"
    # Specify that the path of our rules can use regular expressions
    nginx.ingress.kubernetes.io/use-regex: "true"
    # Connection timeout, 5s by default
    nginx.ingress.kubernetes.io/proxy-connect-timeout: "600"
    # Timeout of data rotation of back-end server, 60s by default
    nginx.ingress.kubernetes.io/proxy-send-timeout: "600"
    # Back end server response timeout, default is 60s
    nginx.ingress.kubernetes.io/proxy-read-timeout: "600"
    # The maximum size of the file uploaded by the client is 20 m by default
    nginx.ingress.kubernetes.io/proxy-body-size: "10m"
    # URL rewrite
    nginx.ingress.kubernetes.io/rewrite-target: /
spec:
  # Routing rules
  rules:
  # Host name, can only be domain name, modify it to your own
  - host: k8s.test.com
    http:
      paths:
      - path:
        backend:
          # The Service Name deployed in the background corresponds to the Tomcat deployed above
          serviceName: tomcat-http
          # The Service Port deployed in the background corresponds to the Tomcat deployed above
          servicePort: 8081