确实，k8s的时代，ingress负载用traefik比nginx方便啊

参考文档：

https://mritd.me/2016/12/06/try-traefik-on-kubernetes/#13ingress

由于微服务架构以及 Docker 技术和 kubernetes 编排工具最近几年才开始逐渐流行，所以一开始的反向代理服务器比如 nginx、apache 并未提供其支持，毕竟他们也不是先知；所以才会出现 Ingress Controller 这种东西来做 kubernetes 和前端负载均衡器如 nginx 之间做衔接；即 Ingress Controller 的存在就是为了能跟 kubernetes 交互，又能写 nginx 配置，还能 reload 它，这是一种折中方案；而最近开始出现的 traefik 天生就是提供了对 kubernetes 的支持，也就是说 traefik 本身就能跟 kubernetes API 交互，感知后端变化，因此可以得知: 在使用 traefik 时，Ingress Controller 已经无卵用了！

apiVersion: extensions/v1beta1
kind: DaemonSet
metadata:
  name: traefik-ingress-lb
  namespace: kube-system
  labels:
    k8s-app: traefik-ingress-lb
spec:
  template:
    metadata:
      labels:
        k8s-app: traefik-ingress-lb
        name: traefik-ingress-lb
    spec:
      terminationGracePeriodSeconds: 60
      hostNetwork: true
      restartPolicy: Always
      containers:
      - image: traefik:latest
        imagePullPolicy: IfNotPresent
        name: traefik-ingress-lb
        resources:
          limits:
            cpu: 200m
            memory: 30Mi
          requests:
            cpu: 100m
            memory: 20Mi
        ports:
        - name: http
          containerPort: 80
          hostPort: 80
        - name: admin
          containerPort: 8580
        args:
        - --web
        - --web.address=:8580
        - --kubernetes

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: traefik-ingress
  namespace: kube-system
spec:
  rules:
  - host: cnxxx.cn
    http:
      paths:
      - path: /
        backend:
          serviceName: tomcat-dm
          servicePort: 8087
  - host: cx.cn
    http:
      paths:
      - path: /
        backend:
          serviceName: nginx-dm
          servicePort: 8088