Kubenetes 中使用 Traefik 作为 Ingress 转发流量

痛定思痛。 2024-04-18 15:12 68阅读 0赞

# Kubenetes 中使用 Traefik 作为 Ingress 转发流量 #

Ingress 就是 Kubernetes 机器外访问集群的入口，将请求的 URL 转发到不同的 Service 上，相当于 Nginx 等代理服务器  
路由信息由 Ingress Controller 提供，Ingress Controller 可以理解为监视器，不断请求 Kubernetes API 实时感知 Service 和 Pod 的状态，结合上下文的 Ingress 生成配置，然后更新反向代理服务器的配置，达到服务发现的作用

Traefik 是一个开源的反向代理与负载均衡工具，能够与常见的微服务系统直接整合，可以实现自动化动态配置

## 通过配置文件部署 Traefik ##

### 配置 ###

*  Ingress-rbac.yaml

用于 Service Account 验证

apiVersion: v1
    kind: ServiceAccount
    metadata:
      name: ingress
      namespace: kube-system
    
    ---
    
    kind: ClusterRoleBinding
    apiVersion: rbac.authorization.k8s.io/v1beta1
    metadata:
      name: ingress
    subjects:
      - kind: ServiceAccount
        name: ingress
        namespace: kube-system
    roleRef:
      kind: ClusterRole
      name: cluster-admin
      apiGroup: rbac.authorization.k8s.io

*  traefik-daemon-set.yaml

使用 DaemonSet 部署 Traefik

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
          serviceAccountName: ingress
          containers:
          - image: traefik
            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
              hostPort: 8580
            args:
            - --web
            - --web.address=:8580
            - --kubernetes

*  traefik-ui.yaml

创建 Traefik 的 UI

apiVersion: v1
    kind: Service
    metadata:
      name: traefik-web-ui
      namespace: kube-system
    spec:
      selector:
        k8s-app: traefik-ingress-lb
      type: NodePort  
      ports:
      - name: web
        port: 80
        targetPort: 8580
    ---
    apiVersion: extensions/v1beta1
    kind: Ingress
    metadata:
      name: traefik-web-ui
      namespace: kube-system
    spec:
      rules:
      - host: traefik-ui.local
        http:
          paths:
          - path: /
            backend:
              serviceName: traefik-web-ui
              servicePort: web

### 部署 ###

kubectl apply -f .

## 通过 Helm 部署 Traefik ##

*  创建 values.yaml

dashboard:
      enabled: true
      domain: dashboard.traefik
    serviceType: LoadBalancer
    rbac:
      enabled: true
    deployment:
      hostPort:
        httpEnabled: true
        httpsEnabled: true
        dashboardEnabled: true

helm install --values values.yaml stable/traefik --name traefik

这样就会启用 Dashboard，更改 Host 指向相应的节点和端口，访问`dashboard.traefik:${PORT}`就可以看到 Dashboard

*  Host

192.168.0.110 dashboard.traefik

*  也可以直接下载 Traefik 的 Helm Release，解压后修改相应的配置后再安装

helm fetch stable/traefik
    
    tar -xvf traefik-1.24.1.tgz
    
    helm install --values values.yaml ./traefik --name traefik

## 部署应用 ##

*  backend-ingress.yaml

apiVersion: extensions/v1beta1
    kind: Ingress
    metadata:
      name: backend-ingress
      namespace: default
    spec:
      rules:
      - host: rest.hellowoodes.com
        http:
          paths:
          - path: /
            backend:
              serviceName: backend
              servicePort: 8080

修改 Host 将域名指向相应的节点 IP

## 测试 ##

*  获取端口

kubectl get service -l app=traefik

NAME               TYPE          CLUSTER-IP      EXTERNAL-IP  PORT(S)                     AGE
    traefik            LoadBalancer  10.106.137.170  <pending>    80:32311/TCP,443:30677/TCP  1s
    traefik-dashboard  ClusterIP     10.108.91.184   <none>       80/TCP                      1s

*  访问相应的 NodeIP 和地址 [http://dashboard.traefik:32311][http_dashboard.traefik_32311]，可以看到 Traefik 的 Dashboard
 *  因为在values.yaml 中已经配置了 `deployment.hostPort.httpEnabled`和`deployment.hostPort.httpsEnabled`，所以也可以直接访问 [dashboard.traefik][]

![traefik-dashboard-page.png][]

*  访问backend 应用

curl http://rest.hellowoodes.com/ping
    Pong%

--------------------

## 参考资料 ##

*  [Helm Traefik][]
 *  [Kubernetes Traefik Installation (helm)][Kubernetes Traefik Installation _helm]
 *  [Kubernetes Ingress Controller][]
 *  [安装traefik ingress][traefik ingress]
 *  [微服务边界路由Traefik：基于京东云Kubernetes集群及Helm Chart][Traefik_Kubernetes_Helm Chart]

[http_dashboard.traefik_32311]: http://dashboard.traefik:32311
[dashboard.traefik]: http://dashboard.traefik
[traefik-dashboard-page.png]: https://imgconvert.csdnimg.cn/aHR0cHM6Ly9oZWxsb3dvb2Rlcy5vc3MtY24tYmVpamluZy5hbGl5dW5jcy5jb20vcGljdHVyZS90cmFlZmlrLWRhc2hib2FyZC1wYWdlLnBuZw?x-oss-process=image/format,png
[Helm Traefik]: https://github.com/helm/charts/tree/master/stable/traefik
[Kubernetes Traefik Installation _helm]: https://8gwifi.org/docs/kube-traefik.jsp
[Kubernetes Ingress Controller]: https://docs.traefik.io/user-guide/kubernetes/#deploy-traefik-using-helm-chart
[traefik ingress]: https://jimmysong.io/kubernetes-handbook/practice/traefik-ingress-installation.html
[Traefik_Kubernetes_Helm Chart]: https://blog.csdn.net/deepbluesolo/article/details/84901427