Kubernetes环境Traefik部署与应用

本作品由Galen Suen采用知识共享署名-非商业性使用-禁止演绎 4.0 国际许可协议进行许可。由原作者转载自个人站点。

更新记录

• 2021-09-17

  1. 部署Traefik时禁用默认Dashboard入口规则；

• 2021-09-30

  1. Traefik版本由v2.5.1更新至v2.5.3；
  2. Traefik Helm Chart版本由v10.3.2更新至v10.3.6；
  3. 修复一些配置文件中的字符转义错误；

概述

本文用于整理基于Kubernetes环境的Traefik部署与应用，实现Ingress Controller、七层/四层反向代理等功能。

本次演练环境为Kubernetes集群环境，环境配置可参考笔者另一篇笔记《Kubernetes集群部署笔记》。

组件版本

• Traefik v2.5.3

• Traefik Helm Chart v10.3.6

配置过程

安装Traefik

• 配置Helm Repo

  helm repo add traefik https://helm.traefik.io/traefik
  helm repo update
  

• 安装Traefik

  本次演练中将traefik安装至kube-system命名空间，可根据需要替换。

  # deployment.replicas=3                设置Traefik部署副本数
  # pilot.dashboard=false                禁用Dashboard中Pilot链接
  # ingressRoute.dashboard.enabled=false 禁用默认Dashboard入口规则（将在后续步骤中手动创建）
  helm upgrade --install --namespace kube-system \
    --set deployment.replicas=3 \
    --set pilot.dashboard=false \
    --set ingressRoute.dashboard.enabled=false \
    traefik traefik/traefik
  

• 其他准备工作

  获取traefik服务的负载均衡器地址。执行该命令，记录返回的EXTERNAL-IP地址备用。本次演练环境中，已将local.choral.io和*.local.choral.io指向该地址。

  kubectl get svc traefik -n kube-system
  

  创建一个用于部署演练用对象的命名空间。本次演练中使用apps-choral命名空间，可根据需要替换。

  kubectl create namespace apps-choral
  

部署Dashboard

• 创建IngressRoute

  创建一个IngressRoute，用于配置api和dashboard的入口规则。

  本次演练中，使用traefik.local.choral.io域名访问Dashboard，可根据需要替换。

  cat <<EOF | kubectl apply -f -
  apiVersion: traefik.containo.us/v1alpha1
  kind: IngressRoute
  metadata:
    name: traefik-dashboard
    namespace: apps-choral
  spec:
    entryPoints:
      - web
    routes:
      - match: Host(\`traefik.local.choral.io\`) && (PathPrefix(\`/dashboard\`) || PathPrefix(\`/api\`))
        kind: Rule
        services:
          - name: api@internal
            kind: TraefikService
  EOF
  

• 启用BasicAuth认证

  首先，创建一个用于保存用户名和密码的Secret，其中的users字段内容可使用htpassword工具生成。本次演练中，认证username和password都是admin。

  cat <<EOF | kubectl apply -f -
  apiVersion: v1
  kind: Secret
  metadata:
    name: traefik-basicauth-secret
    namespace: apps-choral
  data:
    users: |2 # htpasswd -nb admin admin | openssl base64
      YWRtaW46e1NIQX0wRFBpS3VOSXJyVm1EOElVQ3V3MWhReE5xWmM9Cg==
  EOF
  

  创建一个Traefik中间件，用于对请求启用BasicAuth认证。

  cat <<EOF | kubectl apply -f -
  apiVersion: traefik.containo.us/v1alpha1
  kind: Middleware
  metadata:
    name: traefik-basicauth
    namespace: apps-choral
  spec:
    basicAuth:
      realm: traefik.local.choral.io
      secret: traefik-basicauth-secret
  EOF
  

  更新Dashboard的IngressRoute，启用BasicAuth中间件。

  cat <<EOF | kubectl apply -f -
  apiVersion: traefik.containo.us/v1alpha1
  kind: IngressRoute
  metadata:
    name: traefik-dashboard
    namespace: apps-choral
  spec:
    entryPoints:
      - web
    routes:
      - match: Host(\`traefik.local.choral.io\`) && (PathPrefix(\`/dashboard\`) || PathPrefix(\`/api\`))
        kind: Rule
        services:
          - name: api@internal
            kind: TraefikService
        middlewares:
          - name: traefik-basicauth
  EOF
  

七层反向代理

HTTP应用示例

• 部署whoami应用

  创建Deployment，部署whoami应用。

  cat <<EOF | kubectl apply -f -
  apiVersion: apps/v1
  kind: Deployment
  metadata:
    name: whoami
    namespace: apps-choral
  spec:
    replicas: 3
    selector:
      matchLabels:
        app: whoami
    template:
      metadata:
        labels:
          app: whoami
      spec:
        containers:
          - name: whoami
            image: traefik/whoami:latest
            imagePullPolicy: IfNotPresent
            ports:
              - containerPort: 80
  EOF
  

  创建一个用于访问whoami应用的服务。

  cat <<EOF | kubectl apply -f -
  apiVersion: v1
  kind: Service
  metadata:
    name: whoami
    namespace: apps-choral
  spec:
    type: ClusterIP
    ports:
      - protocol: TCP
        port: 80
    selector:
      app: whoami
  EOF
  

  创建一个Ingress，用于配置whoami应用的入口规则。

  cat <<EOF | kubectl apply -f -
  apiVersion: networking.k8s.io/v1
  kind: Ingress
  metadata:
    name: whoami
    namespace: apps-choral
    annotations:
      traefik.ingress.kubernetes.io/router.entrypoints: web
  spec:
    rules:
      - host: local.choral.io
        http:
          paths:
            - path: /
              pathType: Prefix
              backend:
                service:
                  name: whoami
                  port:
                    number: 80
  EOF
  

启用TLS（HTTPS）

本次演练使用静态证书配置TLS，该证书被手动创建，应用于local.choral.io和*.local.choral.io域名。

有关自动证书管理，可参考Cert Manager项目文档。

• 更新Traefik运行参数

  # ports.web.redirectTo=websecure                          启用Web跳转至WebSecure
  # additionalArguments[0]=--entrypoints.websecure.http.tls Ingress默认启用TLS
  helm upgrade --install --namespace kube-system \
    --set deployment.replicas=3 \
    --set pilot.dashboard=false \
    --set ingressRoute.dashboard.enabled=false \
    --set ports.web.redirectTo=websecure \
    --set additionalArguments[0]=--entrypoints.websecure.http.tls \
    traefik traefik/traefik
  

• 创建TLS证书Secret

  从已准备好的证书key文件和crt文件创建Secret。

  kubectl create secret tls local-choral-io-tls -n kube-system --key=local.choral.io.key --cert=local.choral.io.crt
  

• 更新Dashboard的IngressRoute

  更新Dashboard的IngressRoute，启用TLS配置。

  cat <<EOF | kubectl apply -f -
  apiVersion: traefik.containo.us/v1alpha1
  kind: IngressRoute
  metadata:
    name: traefik-dashboard
    namespace: apps-choral
  spec:
    entryPoints:
      - websecure
    routes:
      - match: Host(\`traefik.local.choral.io\`) && (PathPrefix(\`/dashboard\`) || PathPrefix(\`/api\`))
        kind: Rule
        services:
          - name: api@internal
            kind: TraefikService
        middlewares:
          - name: traefik-basicauth
    tls:
      secretName: local-choral-io-tls
  EOF
  

• 更新whoami的Ingress

  更新whoami的Ingress，启用TLS配置。

  cat <<EOF | kubectl apply -f -
  apiVersion: networking.k8s.io/v1
  kind: Ingress
  metadata:
    name: whoami
    namespace: apps-choral
    annotations:
      traefik.ingress.kubernetes.io/router.entrypoints: websecure
  spec:
    tls:
      - secretName: local-choral-io-tls
    rules:
      - host: local.choral.io
        http:
          paths:
            - path: /
              pathType: Prefix
              backend:
                service:
                  name: whoami
                  port:
                    number: 80
  EOF
  

四层反向代理

TCP应用示例

• 更新Traefik运行参数

  更新Traefik运行参数，创建新的EntryPoint。

  # ports.whoamitcp.protocol=TCP     网络协议
  # ports.whoamitcp.port=8081        监听端口
  # ports.whoamitcp.exposedPort=8081 服务公开端口
  # ports.whoamitcp.expose=true      是否暴露端口
  helm upgrade --install --namespace kube-system \
    --set deployment.replicas=3 \
    --set pilot.dashboard=false \
    --set ingressRoute.dashboard.enabled=false \
    --set ports.web.redirectTo=websecure \
    --set additionalArguments[0]=--entrypoints.websecure.http.tls \
    --set ports.whoamitcp.protocol=TCP \
    --set ports.whoamitcp.port=8081 \
    --set ports.whoamitcp.exposedPort=8081 \
    --set ports.whoamitcp.expose=true \
    traefik traefik/traefik
  

• 部署whoamitcp应用

  创建Deployment，部署whoamitcp应用。

  cat <<EOF | kubectl apply -f -
  apiVersion: apps/v1
  kind: Deployment
  metadata:
    name: whoamitcp
    namespace: apps-choral
  spec:
    replicas: 3
    selector:
      matchLabels:
        app: whoamitcp
    template:
      metadata:
        labels:
          app: whoamitcp
      spec:
        containers:
          - name: whoamitcp
            image: traefik/whoamitcp:latest
            imagePullPolicy: IfNotPresent
            ports:
              - protocol: TCP
                containerPort: 8080
  EOF
  

  创建一个用于访问whoamitcp应用的服务。

  cat <<EOF | kubectl apply -f -
  apiVersion: v1
  kind: Service
  metadata:
    name: whoamitcp
    namespace: apps-choral
  spec:
    type: ClusterIP
    ports:
      - protocol: TCP
        port: 8080
    selector:
      app: whoamitcp
  EOF
  

  创建一个IngressRouteTCP，用于配置whoamitcp应用的入口规则。

  cat <<EOF | kubectl apply -f -
  apiVersion: traefik.containo.us/v1alpha1
  kind: IngressRouteTCP
  metadata:
    name: whoamitcp
    namespace: apps-choral
  spec:
    entryPoints:
      - whoamitcp
    routes:
      - match: HostSNI(\`*\`)
        services:
          - name: whoamitcp
            port: 8080
  EOF
  

  验证反向代理和服务运行状态。

  # `10.0.0.201`是`traefik`服务的负载均衡器地址（kubectl get svc traefik -n kube-system）
  echo "Hello" | socat - tcp4:10.0.0.201:8081
  # 终端回显如下内容
  Received: Hello
  

UDP应用示例

• 更新Traefik运行参数

  更新Traefik运行参数，创建新的EntryPoint。

  # ports.whoamiudp.protocol=UDP     网络协议
  # ports.whoamiudp.port=8082        监听端口
  # ports.whoamiudp.exposedPort=8082 服务公开端口
  # ports.whoamiudp.expose=true      是否暴露端口
  helm upgrade --install --namespace kube-system \
    --set deployment.replicas=3 \
    --set pilot.dashboard=false \
    --set ingressRoute.dashboard.enabled=false \
    --set ports.web.redirectTo=websecure \
    --set additionalArguments[0]=--entrypoints.websecure.http.tls \
    --set ports.whoamitcp.protocol=TCP \
    --set ports.whoamitcp.port=8081 \
    --set ports.whoamitcp.exposedPort=8081 \
    --set ports.whoamitcp.expose=true \
    --set ports.whoamiudp.protocol=UDP \
    --set ports.whoamiudp.port=8082 \
    --set ports.whoamiudp.exposedPort=8082 \
    --set ports.whoamiudp.expose=true \
    traefik traefik/traefik
  

• 部署whoamiudp应用

  创建Deployment，部署whoamiudp应用。

  cat <<EOF | kubectl apply -f -
  apiVersion: apps/v1
  kind: Deployment
  metadata:
    name: whoamiudp
    namespace: apps-choral
  spec:
    replicas: 3
    selector:
      matchLabels:
        app: whoamiudp
    template:
      metadata:
        labels:
          app: whoamiudp
      spec:
        containers:
          - name: whoamiudp
            image: traefik/whoamiudp:latest
            imagePullPolicy: IfNotPresent
            ports:
              - protocol: UDP
                containerPort: 8080
  EOF
  

  创建一个用于访问whoamiudp应用的服务。

  cat <<EOF | kubectl apply -f -
  apiVersion: v1
  kind: Service
  metadata:
    name: whoamiudp
    namespace: apps-choral
  spec:
    type: ClusterIP
    ports:
      - protocol: UDP
        port: 8080
    selector:
      app: whoamiudp
  EOF
  

  创建一个IngressRouteUDP，用于配置whoamiudp应用的入口规则。

  cat <<EOF | kubectl apply -f -
  apiVersion: traefik.containo.us/v1alpha1
  kind: IngressRouteUDP
  metadata:
    name: whoamiudp
    namespace: apps-choral
  spec:
    entryPoints:
      - whoamiudp
    routes:
      - services:
          - name: whoamiudp
            port: 8080
  EOF
  

  验证反向代理和服务运行状态。

  # `10.0.0.202`是`traefik-udp`服务的负载均衡器地址（kubectl get svc traefik-udp -n kube-system）
  echo "Hello" | socat - udp4:10.0.0.202:8082
  # 终端回显如下内容
  Received: Hello
  

参考资料

• https://github.com/traefik/traefik-helm-chart

• https://doc.traefik.io/traefik/providers/kubernetes-crd/

• https://doc.traefik.io/traefik/providers/kubernetes-ingress/

• https://doc.traefik.io/traefik/middlewares/http/basicauth/