Service Proxy

ingress => gateway api

• envoy
• contour
• traefik proxy
• haproxy
• metaLB
• nginx
• openelb

ingress controller

• Ingress-nginx(nginx)
• aws-load-balancer-controller(alb)
• ingress-gce
• Traefik

The kubernetes.io/ingress.class annotation is deprecated from kubernetes v1.22+.通过IngressClasses来选择ingress controller。

ingressClassName: nginx

ingress 语法

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: minimal-ingress
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /
spec:
  ingressClassName: nginx-example
  defaultBackend:
    resource:
      apiGroup: k8s.example.com
      kind: StorageBucket
      name: static-assets
  rules:
  - http:
      paths:
      - path: /testpath
        pathType: Prefix
        backend:
          service:
            name: test
            port:
              number: 80

ImplementationSpecific：对于这种路径类型，匹配方法取决于 IngressClass。 具体实现可以将其作为单独的 pathType 处理或者与 Prefix 或 Exact 类型作相同处理。

Exact：精确匹配 URL 路径，且区分大小写。

Prefix：基于以 / 分隔的 URL 路径前缀匹配。匹配区分大小写，并且对路径中的元素逐个完成。 路径元素指的是由 / 分隔符分隔的路径中的标签列表。 如果每个 p 都是请求路径 p 的元素前缀，则请求与路径 p 匹配。

ingressclass没有namespace。

gateway api controller

• cilium
• contour
• GKE
• EKS
• kong
• traefik

ingress-nginx

https://github.com/kubernetes/ingress-nginx

// 部署
 $ kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v0.34.1/deploy/static/provider/baremetal/deploy.yaml

// 验证部署
$ kubectl get pods --all-namespaces -l app.kubernetes.io/name=ingress-nginx --watch

// Detect installed version
POD_NAMESPACE=ingress-nginx
POD_NAME=$(kubectl get pods -n $POD_NAMESPACE -l app.kubernetes.io/name=ingress-nginx -o jsonpath='{.items[0].metadata.name}')
$ kubectl exec -it $POD_NAME -n $POD_NAMESPACE -- /nginx-ingress-controller --version

tls:

https://kubernetes.github.io/ingress-nginx/user-guide/tls/

https://kubernetes.io/zh-cn/docs/concepts/services-networking/ingress/

traefik

traefik2.2+

https://github.com/traefik/traefik

install with helm:

helm repo add traefik https://helm.traefik.io/traefik
helm repo update
helm install --create-namespace traefik -n traefik traefik traefik/traefik -f ./value.yaml

# expose dashboard:
kubectl port-forward -n traefik $(kubectl get pods -n traefik --selector "app.kubernetes.io/name=traefik" --output=name) 9000:9000 --address 0.0.0.0

请求模型

Client => Traefik => Backend

端口:

9000: traefik管理页面端口

重要组件

• Providers: 自动发现平台上的服务.
• Entrypoints: 监听传入的流量，定义接受请求的端口.
• Routers: 分析请求，负责将传入请求连接到负责处理的服务上.
• Middlewares: 在routers转给services之前修改请求.
• Services/LB: 将请求转给应用, 负责配置处理请求的实际服务.

配置

两种配置类型

• 静态配置: 启动时的配置，通过配置文件(/etc/traefik/traefik.[toml|yaml]，环境变量或命令行参数配置 providers和entrypoints等.
• 动态配置: 动态的路由配置，定义系统如何处理请求,从providers获取动态配置.

静态配置:

• entrypoints
• providers
• servertransport
• certificatesresolvers
• api
• ping
• experimental
• hostresolver
• accesslog
• log
• metrics(datadog, influxdb, prometheus,statsd)
• tracing(datadog, elastic, haystack, instana, jaeger, zipkin)

全局配置:

--global.checknewversion
--global.sendanonymoususagge

控制Traefik到Backend的连接的参数serversTransport:

--serversTransport.insecureSkipVerify=true
# self-signed TLS CA.
--serversTransport.rootCAs=foo.crt,bar.crt
--serversTransport.maxIdleConnsPerHost=7
--serversTransport.forwardingTimeouts.dialTimeout=1s
--serversTransport.forwardingTimeouts.responseHeaderTimeout=1s
--serversTransport.forwardingTimeouts.idleConnTimeout=1s

kubernetes provider

kubernetes provider有三种类型

• Ingress
• IngressRoute
• Gateway API

https & tls

traefik的证书可以是手动创建证书，也可以通过let’s encrypt自动创建

---
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
  name: name
  namespace: ns
spec:
  tls:
    secretName: my-tls

通过Let’s encrypt来自动创建证书有三种验证方式（tls, http, dns).

- "--certificatesresolvers.myresolver.acme.httpchallenge=true"
- "--certificatesresolvers.myresolver.acme.httpchallenge.entrypoint=web"
- "--certificatesresolvers.myresolver.acme.tlschallenge=true"
- "--certificatesresolvers.myresolver.acme.tlschallenge.entrypoint=websecure"
- "--certificatesresolvers.myresolver.acme.email=canux.cheng@arm.com"
- "--certificatesresolvers.myresolver.acme.storage=acme.json"