Question

我需要在azure k8s上配置Ingress Nginx，我的问题是是否有可能在一个命名空间中配置ingress等。 ingress-nginx和其他名称空间中的某些服务，例如。资源？我的文件看起来像这样：

# ingress-nginx.yaml
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: nginx-ingress-controller
  namespace: ingress-nginx
spec:
  replicas: 3
  selector:
    matchLabels:
      app: ingress-nginx
  template:
    metadata:
      labels:
        app: ingress-nginx
      annotations:
        prometheus.io/port: '10254'
        prometheus.io/scrape: 'true' 
    spec:
      containers:
        - name: nginx-ingress-controller
          image: quay.io/kubernetes-ingress-controller/nginx-ingress-controller:0.12.0
          args:
            - /nginx-ingress-controller
            - --default-backend-service=$(POD_NAMESPACE)/default-http-backend
            - --configmap=$(POD_NAMESPACE)/nginx-configuration
            - --tcp-services-configmap=$(POD_NAMESPACE)/tcp-services
            - --udp-services-configmap=$(POD_NAMESPACE)/udp-services
            - --annotations-prefix=nginx.ingress.kubernetes.io
            - --publish-service=$(POD_NAMESPACE)/ingress-nginx
          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: 1
          readinessProbe:
            failureThreshold: 3
            httpGet:
              path: /healthz
              port: 10254
              scheme: HTTP
            periodSeconds: 10
            successThreshold: 1
            timeoutSeconds: 1

# configmap.yaml
kind: ConfigMap
apiVersion: v1
metadata:
  name: nginx-configuration
  namespace: ingress-nginx
  labels:
    app: ingress-nginx
---
kind: ConfigMap
apiVersion: v1
metadata:
  name: tcp-services
  namespace: ingress-nginx
---
kind: ConfigMap
apiVersion: v1
metadata:
  name: udp-services
  namespace: ingress-nginx
---
# default-backend.yaml
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: default-http-backend
  labels:
    app: default-http-backend
  namespace: ingress-nginx
spec:
  replicas: 1
  selector:
    matchLabels:
      app: default-http-backend
  template:
    metadata:
      labels:
        app: default-http-backend
    spec:
      terminationGracePeriodSeconds: 60
      containers:
      - name: default-http-backend
        # Any image is permissible as long as:
        # 1. It serves a 404 page at /
        # 2. It serves 200 on a /healthz endpoint
        image: gcr.io/google_containers/defaultbackend:1.4
        livenessProbe:
          httpGet:
            path: /healthz
            port: 8080
            scheme: HTTP
          initialDelaySeconds: 30
          timeoutSeconds: 5
        ports:
        - containerPort: 8080
        resources:
          limits:
            cpu: 10m
            memory: 20Mi
          requests:
            cpu: 10m
            memory: 20Mi
---
apiVersion: v1
kind: Service
metadata:
  name: default-http-backend
  namespace: ingress-nginx
  labels:
    app: default-http-backend
spec:
  ports:
  - port: 80
    targetPort: 8080
  selector:
    app: default-http-backend

kind: Service
apiVersion: v1
metadata:
  name: ingress-nginx
  namespace: ingress-nginx
  labels:
    app: ingress-nginx
spec:
  externalTrafficPolicy: Local
  type: LoadBalancer
  selector:
    app: ingress-nginx
  ports:
  - name: http
    port: 80
    targetPort: http
  - name: https
    port: 443
    targetPort: https

        # app-ingress.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: app-ingress
  namespace: ingress-nginx
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/rewrite-target: /
spec:
  tls:
    - hosts:
      - api-sand.fake.com
  rules:
  - host: api-sand.fake.com
    http:
      paths:
      - backend:
          serviceName: api-sand
          servicePort: 80
        path: /

然后我在 resources名称空间中运行了一些应用程序，问题是我遇到了以下错误

error obtaining service endpoints: error getting service resources/api-sand from the cache: service resources/api-sand was not found

如果我将api-sand部署在与ingress相同的名称空间中，则该服务可以正常工作。

Answer 1

对于那些不熟悉Kubernetes尤其是其入口选项的人，我想进一步简化答案。为了使Ingress正常工作，需要提供2个单独的条件：

入口控制器（基本上是一个单独的Pod / Deployment和可用于利用路由和代理的服务。基于例如nginx容器）；
进入规则（单独的Kubernetes 与kind: Ingress合作。仅当Ingress生效控制器已经deployed）

现在， Ingress Controller可以部署在任何名称空间中，并且实际上通常部署在与应用服务分开的名称空间中。它可以立即查看集群中所有名称空间中的Ingress规则，并将其提取。
但是，Ingress规则必须位于其配置的应用程序所在的名称空间中。

有一些解决方法，但这是最常见的方法。

Answer 2

与其在app-ingress命名空间中创建入口ingress-nginx，不应该在拥有服务api-sand和pod的命名空间中创建入口。

或者有一种方法可以通过externalName。checkout Kubernetes Cross Namespace Ingress Network

进入一个命名空间并在另一个命名空间中实现服务。

以下是here中引用的示例。

kind: Service
apiVersion: v1
metadata:
  name: my-service
spec:
  type: ExternalName
  externalName: test-service.namespacename.svc.cluster.local

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: example-ingress
  annotations:
    kubernetes.io/ingress.class: "nginx"
spec:
  rules:
  - host: example.com
    http:
      paths:
      - path: /
        backend:
          serviceName: my-service
          servicePort: 80

Answer 3

实际上有可能，您可以在名称空间A中使用ExternalName类型定义入口和服务，而ExternalName则在名称空间B中指向服务的DNS。有关更多详细信息，请参考以下答案：https://stackoverflow.com/a/51899301/2995449 < / p>

Answer 4

每个入口资源都有一个 way to configure 默认后端，尽管文档说它通常在入口控制器级别配置。

例如：

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: myingress
  namespace: myns
spec: 
  defaultBackend:
    service:
      name: default-http-backend
      port: 
        number: 80
...

此处 default-http-backend 必须定义在与入口资源相同的命名空间中。

不同名称空间中k8的入口配置

4 个答案: