Ingress-Nginx

注意：

　　 本文只用的ingress-nginx版本为0.24.1,可在官方网站自行下载

　　https://github.com/kubernetes/ingress-nginx

一、Ingress-Nginx工作原理

1.ingress controller通过和kubernetes api交互，动态的去感知集群中ingress规则变化，
2.然后读取它，按照自定义的规则，规则就是写明了哪个域名对应哪个service，生成一段nginx配置，
3.再写到nginx-ingress-control的pod里，这个Ingress controller的pod里运行着一个Nginx服务，控制器会把生成的nginx配置写入/etc/nginx.conf文件中，
4.然后reload一下使配置生效。以此达到域名分配置和动态更新的问题。

二、搭建

　　kubnet ~]$ kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/nginx-0.24.1/deploy/mandatory.yaml

　　kubnet ~]$ kubectl get pods -n ingress-nginx

　　kubnet ~]$ mkdir ingress

　　kubnet ingress]$ vim deploy-demo.yml　

apiVersion: v1
kind: Service
metadata:
  name: myapp
  namespace: default
spec:
  selector:
    app: myapp
    release: stable
  ports:
  - name: myapp
    port: 80
    targetPort: 80
---
            
apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp
  namespace: default
spec:
  selector:
    matchLabels:
      app: myapp
      release: stable
   replicas: 3
   template:
     metadata:
       labels:
         app: myapp
         release: stable
      spec:
        containers:
        - name: myapp
          image: fangwenkai/kubernetes:v1.15
          imagePullPolicy: IfNotPresent
        ports:
        - name: myapp
    　　containerPort: 80   

　　kubnet ingress]$ kubectl apply -f deploy-demo.yml

　　kubnet ingress]$ kubectl get svc

　　

　　kubnet ingress]$ kubectl get deploy

　　

　　kubnet ingress]$ kubectl get pods

　　

　　kubnet ingress]$ wget https://raw.githubusercontent.com/kubernetes/ingress-nginx/nginx-0.24.1/deploy/provider/baremetal/service-nodeport.yaml

　　kubnet ingress]$ vim service-nodeport.yaml

apiVersion: v1
kind: Service
metadata:
 name: ingress-nginx
 namespace: ingress-nginx
 labels:
   app.kubernetes.io/name: ingress-nginx
   app.kubernetes.io/part-of: ingress-nginx
spec:
  type: NodePort
  ports:
  - name: http
  　port: 80
  　targetPort: 80
  　nodePort: 30001                                 // 手动指定服务器端口,不指定就是默认
  　protocol: TCP
  - name: https
    port: 443
  　targetPort: 443
  　nodePort: 30443                                 // 手动指定服务器端口,不指定就是默认
    protocol: TCP
  selector:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx

  ---

　　kubnet ingress]$ kubectl get svc -n ingress-nginx

　　

　　kubnet ingress]$ curl 192.168.23.101:30001    // 访问本机地址,此时结果应该是404

　　kubnet ingress]$ vim ingress-myapp.yml

　　

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
 name: ingress-myapp
 namespace: default
 annotations:
   kubernetes.io/ingress.class: "nginx"
spec:
  rules:
  - host: myapp.kaikai.com
    http:
     paths:
     - path:
       backend:
        serviceName: myapp
        servicePort: 80

　　kubnet ingress]$ kubectl get ingress

　　kubnet ingress]$ curl myapp.kaikai.com:30001       // 能看到后端Pod结果

　　或者浏览器直接访问地址