前言

k8s集群服务部署好之后，需要对外提域名访问，这时候就需要ingress-nginx了，今天来给大家分享一下

一、部署配置Ingress

1、获取配置文件

#文件已下载到本地
https://github.com/kubernetes/ingress-nginx/tree/nginx-0.20.0/deploy

2、准备镜像

unzip ingress-nginx-nginx-0.20.0.zip
cd ingress-nginx-nginx-0.20.0/deploy/
vim mandatory.yaml     #其他文件的集合
#编辑mandatory.yaml文件，将defaultbackend镜像地址改成阿里云的镜像地址(如下图)
image: registry.cn-hangzhou.aliyuncs.com/allinpay/defaultbackend-amd64:v1.5

3、安装

kubectl apply -f mandatory.yaml

#稍等片刻，使用下列命令查询
kubectl get namespace
kubectl get pods -n ingress-nginx

4、创建后端pod和service (pod-B、service-B)

vim deploy-demo.yaml
apiVersion: v1
kind: Service
metadata:
  name: myapp
  namespace: default
spec:
  selector:
    app: myapp
    release: canary
  ports:
  - name: http
    targetPort: 80
    port: 80
---　　
apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp-deploy
  namespace: default
spec:
  replicas: 3
  selector:
    matchLabels:
      app: myapp
      release: canary
  template:
    metadata:
      labels:
        app: myapp
        release: canary
    spec:
      containers:
      - name: myapp
        image: ikubernetes/myapp:v2
        ports:
        - name: http
          containerPort: 80

#应用配置
kubectl apply -f deploy-demo.yaml
#查看
kubectl get pods

5、创建service-A

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
    protocol: TCP
    nodePort: 30080
  - name: https
    port: 443
    targetPort: 443
    protocol: TCP
    nodePort: 30443
  selector:
    app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx

#应用配置
kubectl apply -f service-nodeport.yaml

#查看
kubectl get svc -n ingress-nginx

在外部浏览器中中访问：ip:30080

此时报错的原因是因为没有生成ingress-controller关联到service-B的ingress规则；

6、定义ingress规则

定义ingress规则，此间规则会自动注入到ingress-controller(pod)的nginx.conf中；
ingress-controller是直接关联到service-B的，但是中间由ingress来生成各种规则；

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

此时ingress-controller的nginx.conf中会自动生成一个server段的配置，也就是一个nginx的虚拟主机的字段，还包括upstream配置等；
upstream自动代理到后端pod（pod-B），这些都是自动生成，所以就实现了自动生成配置，自动更改配置等；
只需要改此yaml文件即可；

#应用配置
kubectl apply -f ingress-myapp.yaml

在外部主机上配置好host文件

然后在浏览器中再访问，发现已经可以访问到后端pod了

二、使用https

1、创建k8s证书（要注意和后端的pod使用相同的namespace）

kubectl -n default  create secret tls ingress-test --key /home/centos/cert/cash432.key --cert /home/centos/cert/cash432.crt

2、创建ingress规则

注意namespace的相同性，要不然证书无法生效

vim ingress-myapp-cash432.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: ingress-myapp
  namespace: default
  annotations:
    kubernetes.io/ingress.class: "nginx"
    kubernetes.io/secure-backends: "true"
    kubernetes.io/ssl-passthrough: "true"
spec:
  tls:
  - hosts:
    - myapp.cash432.xyz
    secretName: ingress-test
  rules:
  - host: myapp.cash432.xyz
    http:
      paths:
      - path:
        backend:
          serviceName: myapp
          servicePort: 80

#应用配置
kubectl apply -f ingress-myapp-cash432.yaml

浏览器访问