Ingress是什么
Ingress :简单理解就是个规则定义;比如说某个域名对应某个 service,即当某个域名的请求进来时转发给某个 service;这个规则将与 Ingress Controller 结合,然后 Ingress Controller 将其动态写入到负载均衡器配置中,从而实现整体的服务发现和负载均衡
Ingress Controller
实质上可以理解为是个监视器,Ingress Controller 通过不断地跟 kubernetes API 打交道,实时的感知后端 service、pod 等变化,比如新增和减少 pod,service 增加与减少等;当得到这些变化信息后,Ingress Controller 再结合Ingress 生成配置,然后更新反向代理负载均衡器,并刷新其配置,达到服务发现的作用
安装Ingress
kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/master/deploy/mandatory.yaml #安装ingress-Controller
创建一后端pod service:
[root@master ingress]# kubectl apply -f deploy-demo.yaml[root@master ingress]# cat deploy-demo.yaml apiVersion: v1kind: Servicemetadata: name: myapp namespace: defaultspec: selector: app: myapp release: canary ports: - name: http targetPort: 80 port: 80---apiVersion: apps/v1kind: Deploymentmetadata: name: myapp-deploy namespace: defaultspec: 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
创建一个用于暴露端口的service
[root@master baremetal]# kubectl apply -f service-nodeport.yaml[root@master baremetal]# cat service-nodeport.yaml apiVersion: v1kind: Servicemetadata: name: ingress-nginx namespace: ingress-nginx labels: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginxspec: 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
创建Ingress文件
[root@master ingress]# kubectl apply -f ingress-myapp.yaml[root@master ingress]# cat ingress-myapp.yaml apiVersion: extensions/v1beta1kind: Ingressmetadata: name: ingress-myapp namespace: default annotations: kubernetes.io/ingress.class: "nginx"spec: rules: - host: myapp.template.com http: paths: - path: backend: serviceName: myapp servicePort: 80
查看信息
[root@master ingress]# kubectl get ingressNAME HOSTS ADDRESS PORTS AGEingress-myapp myapp.template.com 80 5h55[root@master ingress]# kubectl get svcNAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGEmyapp ClusterIP 10.98.30.144
80/TCP 4h7m[root@master ingress]# kubectl get podsNAME READY STATUS RESTARTS AGEmyapp-deploy-7b64976db9-lfnlv 1/1 Running 0 6h30mmyapp-deploy-7b64976db9-nrfgs 1/1 Running 0 6h30mmyapp-deploy-7b64976db9-pbqvh 1/1 Running 0 6h30m#访问[root@master ingress]# curl myapp.template.com:30080Hello MyApp | Version: v2 | Pod Name
Ingress使用ssl
[root@master ingress]# cat tomcat-deploy.yaml apiVersion: v1kind: Servicemetadata: name: tomcat namespace: defaultspec: selector: app: tomcat release: canary ports: - name: http targetPort: 8080 port: 8080 - name: ajp targetPort: 8009 port: 8009 ---apiVersion: apps/v1kind: Deploymentmetadata: name: tomcat-deploy namespace: defaultspec: replicas: 3 selector: matchLabels: app: tomcat release: canary template: metadata: labels: app: tomcat release: canary spec: containers: - name: tomcat image: tomcat:8.5-alpine ports: - name: http containerPort: 8080 - name: ajp containerPort: 8009[root@master ingress]# kubectl apply -f tomcat-deploy.yaml [root@master ingress]# openssl genrsa -out tls.key 2048[root@master ingress]# openssl req -new -x509 -key tls.key -out tls.crt -subj /C=CN/ST=Beijing/L=Beijing/O=DevOps/CN=tomcat.template.com[root@master ingress]# kubectl create secret tls tomcat-ingress-secret --cert=tls.crt --key=tls.key[root@master ingress]# kubectl get secretNAME TYPE DATA AGEdefault-token-962mh kubernetes.io/service-account-token 3 32htomcat-ingress-secret kubernetes.io/tls 2 66m[root@master ingress]# cat ingress-tomcat-tls.yaml apiVersion: extensions/v1beta1kind: Ingressmetadata: name: ingress-tomcat-tls namespace: default annotations: kubernetes.io/ingress.class: "nginx"spec: tls: - hosts: - tomcat.template.com secretName: tomcat-ingress-secret rules: - host: tomcat.template.com http: paths: - path: backend: serviceName: tomcat servicePort: 8080[root@master ingress]# kubectl apply -f ingress-tomcat-tls.yaml[root@master ingress]# curl -k https://tomcat.template.com:30443 #测试访问