Kubernetes的Ingress是啥

目录

• 一、什么是Ingress
• 二、部署Nginx Ingress Controller
• 三、部署一个Service将Nginx服务暴露出去
• 四、部署一个我们自己的服务Cafe
• 五、部署ingress依赖的证书
• 六、部署ingress对象
• 七、访问ingress代理的服务
  • 1.访问coffee
  • 2.访问tea
  • 3.访问不存在的页面cqh

一、什么是Ingress

Ingress对象，其实就是对“反向代理”的一种抽象，简单的说就是一个全局的负载均衡器，可以通过访问URL定位到后端的Service

有了Ingress这个抽象，K8S就不需要关心Ingress的细节了，实际使用时，只需要选择一个具体的Ingress Controller部署就行了，业界常用的反向代理项目有：Nginx、HAProxy、Envoy、Traefik，都已经成为了K8S专门维护的Ingress Controller
一个Ingress对象的主要内容，就类似Nginx的配置文件描述，对应的转发规则就是ingressRule，
有了Ingress这个对象，用户就可以根据自己的需求选择Ingress Controller，例如，如果应用对代理服务的中断非常敏感，可以使用Treafik这样的Ingress Controller

Ingress工作在七层，Service工作在四层，当想要在Kubernetes里为应用进行TLS配置等HTTPS相关操作时，都必须通过Ingress来进行

LoadBalancer的Service也会在公有云创建负载均衡，但是是一个Servcie对应一个，太浪费了

以下以演示部署一个Nginx Ingress Controller，并代理一个我们自己创建的服务coffee

Nginx Ingress Controller 官网地址：https://kubernetes.github.io/ingress-nginx
依赖的其他github相关yaml文件：https://github.com/nginxinc/kubernetes-ingress/tree/master/examples/complete-example

二、部署Nginx Ingress Controller

kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/master/deploy/static/mandatory.yaml

内容如下

apiVersion: v1
kind: Namespace
metadata:
  name: ingress-nginx
  labels:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx

---

kind: ConfigMap
apiVersion: v1
metadata:
  name: nginx-configuration
  namespace: ingress-nginx
  labels:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx

---
kind: ConfigMap
apiVersion: v1
metadata:
  name: tcp-services
  namespace: ingress-nginx
  labels:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx

---
kind: ConfigMap
apiVersion: v1
metadata:
  name: udp-services
  namespace: ingress-nginx
  labels:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx

---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: nginx-ingress-serviceaccount
  namespace: ingress-nginx
  labels:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx

---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
  name: nginx-ingress-clusterrole
  labels:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx
rules:
  - apiGroups:
      - ""
    resources:
      - configmaps
      - endpoints
      - nodes
      - pods
      - secrets
    verbs:
      - list
      - watch
  - apiGroups:
      - ""
    resources:
      - nodes
    verbs:
      - get
  - apiGroups:
      - ""
    resources:
      - services
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - ""
    resources:
      - events
    verbs:
      - create
      - patch
  - apiGroups:
      - "extensions"
      - "networking.k8s.io"
    resources:
      - ingresses
    verbs:
      - get
      - list
      - watch
  - apiGroups:
      - "extensions"
      - "networking.k8s.io"
    resources:
      - ingresses/status
    verbs:
      - update

---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: Role
metadata:
  name: nginx-ingress-role
  namespace: ingress-nginx
  labels:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx
rules:
  - apiGroups:
      - ""
    resources:
      - configmaps
      - pods
      - secrets
      - namespaces
    verbs:
      - get
  - apiGroups:
      - ""
    resources:
      - configmaps
    resourceNames:
      # Defaults to "<election-id>-<ingress-class>"
      # Here: "<ingress-controller-leader>-<nginx>"
      # This has to be adapted if you change either parameter
      # when launching the nginx-ingress-controller.
      - "ingress-controller-leader-nginx"
    verbs:
      - get
      - update
  - apiGroups:
      - ""
    resources:
      - configmaps
    verbs:
      - create
  - apiGroups:
      - ""
    resources:
      - endpoints
    verbs:
      - get

---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: RoleBinding
metadata:
  name: nginx-ingress-role-nisa-binding
  namespace: ingress-nginx
  labels:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: nginx-ingress-role
subjects:
  - kind: ServiceAccount
    name: nginx-ingress-serviceaccount
    namespace: ingress-nginx

---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
  name: nginx-ingress-clusterrole-nisa-binding
  labels:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: nginx-ingress-clusterrole
subjects:
  - kind: ServiceAccount
    name: nginx-ingress-serviceaccount
    namespace: ingress-nginx

---

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-ingress-controller
  namespace: ingress-nginx
  labels:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx
spec:
  replicas: 1
  selector:
    matchLabels:
      app.kubernetes.io/name: ingress-nginx
      app.kubernetes.io/part-of: ingress-nginx
  template:
    metadata:
      labels:
        app.kubernetes.io/name: ingress-nginx
        app.kubernetes.io/part-of: ingress-nginx
      annotations:
        prometheus.io/port: "10254"
        prometheus.io/scrape: "true"
    spec:
      # wait up to five minutes for the drain of connections
      terminationGracePeriodSeconds: 300
      serviceAccountName: nginx-ingress-serviceaccount
      nodeSelector:
        kubernetes.io/os: linux
      containers:
        - name: nginx-ingress-controller
          image: quay.io/kubernetes-ingress-controller/nginx-ingress-controller:0.26.1
          args:
            - /nginx-ingress-controller
            - --configmap=$(POD_NAMESPACE)/nginx-configuration
            - --tcp-services-configmap=$(POD_NAMESPACE)/tcp-services
            - --udp-services-configmap=$(POD_NAMESPACE)/udp-services
            - --publish-service=$(POD_NAMESPACE)/ingress-nginx
            - --annotations-prefix=nginx.ingress.kubernetes.io
          securityContext:
            allowPrivilegeEscalation: true
            capabilities:
              drop:
                - ALL
              add:
                - NET_BIND_SERVICE
            # www-data -> 33
            runAsUser: 33
          env:
            - name: POD_NAME
              valueFrom:
                fieldRef:
                  fieldPath: metadata.name
            - name: POD_NAMESPACE
              valueFrom:
                fieldRef:
                  fieldPath: metadata.namespace
          ports:
            - name: http
              containerPort: 80
            - name: https
              containerPort: 443
          livenessProbe:
            failureThreshold: 3
            httpGet:
              path: /healthz
              port: 10254
              scheme: HTTP
            initialDelaySeconds: 10
            periodSeconds: 10
            successThreshold: 1
            timeoutSeconds: 10
          readinessProbe:
            failureThreshold: 3
            httpGet:
              path: /healthz
              port: 10254
              scheme: HTTP
            periodSeconds: 10
            successThreshold: 1
            timeoutSeconds: 10
          lifecycle:
            preStop:
              exec:
                command:
                  - /wait-shutdown

---

1.上面的YAML文件，定义了一个使用nginx-ingress-controller镜像的Pod，Pod的启动命令需要使用Pod的Namespace作为参数，Pod本身，本身就一个监听ingress对象以及它所代理的后端Service变化的控制器

2.当一个新的Ingress对象由用户创建后，nginx-ingress-controller就会根据ingress对象里的内容，生成一份对应的Nginx配置文件，并使用这个配置文件启动一个Nginx服务
如果Ingress对象是被更新，nginx-ingress-controller就会更新这个配置文件
注意：如果只是被代理的Service对象被更新，nginx-ingress-controller所管理的服务是不需要重新加载的，因为nginx-ingress-controller通过Nginx Lua方案实现了Nginx Upstream的动态配置

3.nginx-ingress-controller允许通过K8S的ConfigMap对象对上述Nginx配置文件定制，ConfigMap名字需要以参数方式传递给nginx-ingress-controller，在ConfigMap里添加的字段会生成到nginx配置文件当中

一个Nginx Ingress Controller其实是一个可以根据Ingress对象和被代理后端Service的变化，来自动更新的Nginx负载均衡器

三、部署一个Service将Nginx服务暴露出去

为了让用户能访问这个Nginx，我们创建一个Service把Nginx服务暴露出去，通过NodePort方式

kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/master/deploy/static/provider/baremetal/service-nodeport.yaml

格式如下

apiVersion: v1
kind: Service
metadata:
  name: ingress-nginx
  namespace: ingress-nginx
  labels:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx
spec:
  type: NodePort
  ports:
    - name: http
      port: 80
      targetPort: 80
      protocol: TCP
    - name: https
      port: 443
      targetPort: 443
      protocol: TCP
  selector:
    app.kubernetes.io/name: ingress-nginx
    app.kubernetes.io/part-of: ingress-nginx
---

这个service的工作，就是将带有ingress-nginx标签的Pod的80和443端口暴露出去

我们查看一下这个svc

 ~ kubectl get svc -n ingress-nginx
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
ingress-nginx NodePort 10.43.33.55 <none> 80:30164/TCP,443:32229/TCP 107m

通过Node的30164这个端口就可以访问这个servcie，随便选择一个Node就可以，这里使用72.17.0.215访问一下

curl 172.17.0.215:30164
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>openresty/1.15.8.2</center>
</body>
</html>

四、部署一个我们自己的服务Cafe

这是会创建Deployment和Servcie，cafe.yaml

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: coffee
spec:
  replicas: 2
  selector:
    matchLabels:
      app: coffee
  template:
    metadata:
      labels:
        app: coffee
    spec:
      containers:
      - name: coffee
        image: nginxdemos/hello:plain-text
        ports:
        - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: coffee-svc
spec:
  ports:
  - port: 80
    targetPort: 80
    protocol: TCP
    name: http
  selector:
    app: coffee
---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: tea
spec:
  replicas: 3
  selector:
    matchLabels:
      app: tea 
  template:
    metadata:
      labels:
        app: tea 
    spec:
      containers:
      - name: tea 
        image: nginxdemos/hello:plain-text
        ports:
        - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: tea-svc
  labels:
spec:
  ports:
  - port: 80
    targetPort: 80
    protocol: TCP
    name: http
  selector:
    app: tea

运行

➜ ingress-test kubectl apply -f cafe.yaml
deployment.extensions/coffee created
service/coffee-svc created
deployment.extensions/tea created
service/tea-svc created
➜ ingress-test kubectl get deployment
NAME READY UP-TO-DATE AVAILABLE AGE
coffee 2/2 2 2 66s
tea 3/3 3 3 66s
➜ ingress-test kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
coffee-svc ClusterIP 10.43.216.45 <none> 80/TCP 70s
kubernetes ClusterIP 10.43.0.1 <none> 443/TCP 69d
tea-svc ClusterIP 10.43.208.95 <none> 80/TCP 69s

可以看到对应的tea-svc和coffee-svc被创建出来了

五、部署ingress依赖的证书

cafe-secret.yaml

apiVersion: v1
kind: Secret
metadata:
  name: cafe-secret
type: Opaque
data:
  tls.crt: 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
  tls.key: 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

执行创建

➜ ingress-test kubectl apply -f cafe-secret.yaml
secret/cafe-secret created
➜ ingress-test kubectl get secrets
NAME TYPE DATA AGE
cafe-secret Opaque 2 17s

六、部署ingress对象

文件如下,cafe-ingress.yaml

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: cafe-ingress
spec:
  tls:
  - hosts:
    - cafe.example.com
    secretName: cafe-secret
  rules:
  - host: cafe.example.com
    http:
      paths:
      - path: /tea
        backend:
          serviceName: tea-svc
          servicePort: 80
      - path: /coffee
        backend:
          serviceName: coffee-svc
          servicePort: 80

可以看到，该ingress指定了/conffee和/tea这两个path，分别指向coffee-svc和tea-svc，我们执行部署

➜ ingress-test kubectl apply -f cafe-ingress.yaml
ingress.extensions/cafe-ingress created
➜ ingress-test kubectl get ingress
NAME HOSTS ADDRESS PORTS AGE
cafe-ingress cafe.example.com 10.43.33.55 80, 443 7s

➜ ingress-test kubectl describe ingress cafe-ingres
Name: cafe-ingress
Namespace: default
Address: 10.43.33.55
Default backend: default-http-backend:80 (<none>)
TLS:
  cafe-secret terminates cafe.example.com
Rules:
  Host Path Backends
  ---- ---- --------
  cafe.example.com
                    /tea tea-svc:80 (10.42.0.41:80,10.42.0.42:80,10.42.2.185:80)
                    /coffee coffee-svc:80 (10.42.0.40:80,10.42.2.184:80)
Annotations:
  field.cattle.io/publicEndpoints: [{"addresses":["10.43.33.55"],"port":443,"protocol":"HTTPS","serviceName":"default:tea-svc","ingressName":"default:cafe-ingress","hostname":"cafe.example.com","path":"/tea","allNodes":true},{"addresses":["10.43.33.55"],"port":443,"protocol":"HTTPS","serviceName":"default:coffee-svc","ingressName":"default:cafe-ingress","hostname":"cafe.example.com","path":"/coffee","allNodes":true}]
  kubectl.kubernetes.io/last-applied-configuration: {"apiVersion":"extensions/v1beta1","kind":"Ingress","metadata":{"annotations":{},"name":"cafe-ingress","namespace":"default"},"spec":{"rules":[{"host":"cafe.example.com","http":{"paths":[{"backend":{"serviceName":"tea-svc","servicePort":80},"path":"/tea"},{"backend":{"serviceName":"coffee-svc","servicePort":80},"path":"/coffee"}]}}],"tls":[{"hosts":["cafe.example.com"],"secretName":"cafe-secret"}]}}

Events:
  Type Reason Age From Message
  ---- ------ ---- ---- -------
  Normal CREATE 2m13s nginx-ingress-controller Ingress default/cafe-ingress
  Normal UPDATE 2m13s (x2 over 2m13s) nginx-ingress-controller Ingress default/cafe-ingress

可以看到，这个Ingress的核心部署是Rule字段

Rules:
  Host Path Backends
  ---- ---- --------
  cafe.example.com
                    /tea tea-svc:80 (10.42.0.41:80,10.42.0.42:80,10.42.2.185:80)
                    /coffee coffee-svc:80 (10.42.0.40:80,10.42.2.184:80)

定义的HOST是cafe.example.com，分别对应两条转发规则/tea和/coffee

七、访问ingress代理的服务

拉下来，我们就可以通过访问这个ingress的地址和端口，访问到我们部署的应用了
地址分别是https://cafe.example.com/coffee:443和https://cafe.example.com/tea:443

我们先把设置一下入口的环境变量导入，指定Node的IP和HTTPS对应的端口号

IC_IP=172.17.0.215
IC_HTTPS_PORT=32229

1.访问coffee

curl --resolve cafe.example.com:$IC_HTTPS_PORT:$IC_IP https://cafe.example.com:$IC_HTTPS_PORT/coffee --insecur
Server address: 10.42.0.40:80
Server name: coffee-bbd45c6-jp6bz
Date: 23/Oct/2019:06:35:35 +0000
URI: /coffee
Request ID: df63447fcacfc2ff0acd1f8a9b30d334

2.访问tea

curl --resolve cafe.example.com:$IC_HTTPS_PORT:$IC_IP https://cafe.example.com:$IC_HTTPS_PORT/tea --insecure
Server address: 10.42.2.185:80
Server name: tea-5857f7786b-qkpn7
Date: 23/Oct/2019:06:37:17 +0000
URI: /tea
Request ID: a5da5ff4d869c3978aed450738b44706

3.访问不存在的页面cqh

curl --resolve cafe.example.com:$IC_HTTPS_PORT:$IC_IP https://cafe.example.com:$IC_HTTPS_PORT/cqh --insecure
<html>
<head><title>404 Not Found</title></head>
<body>
<center><h1>404 Not Found</h1></center>
<hr><center>openresty/1.15.8.2</center>
</body>
</html>

可以看到，当我们请求没有匹配任何一条IngressRule，会返回一个Nginx的404页面

到这，我们已经成功的部署并使用ingress代理了我们的服务