kubernetes Service 暴露服务的几种方式

绝地灬酷狼 2022-05-17 07:21 273阅读 0赞

kubernetes service暴露服务到目前为止，一共有以下几种方法

**ClusterIP 方式**

kubernetes 默认就是这种方式，是集群内部访问的方式

spec:
      clusterIP: 10.0.0.1
      ports:
      - name: http

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

**NodePort 方式**

NodePort方式主要通过节点IP加端口的形式暴露端口  
访问方式：protocol://:.

heapster                10.3.129.117   <nodes>       80:30003/TCP    14d
    
    apiVersion: v1
    kind: Service
    metadata:
      annotations:
        kubectl.kubernetes.io/last-applied-configuration: |
          {
       "apiVersion":"v1","kind":"Service","metadata":{
       "annotations":{},"creationTimestamp":"2017-05-24T06:38:16Z","labels":{
       "kubernetes.io/name":"heapster","plugin":"heapster"},"name":"heapster","namespace":"kube-system","resourceVersion":"173906247","selfLink":"/api/v1/namespaces/kube-system/services/heapster","uid":"91470fbb-404b-11e7-ba41-5254eec04736"},"spec":{
       "clusterIP":"10.3.129.117","externalTrafficPolicy":"Cluster","ports":[{
       "nodePort":30003,"port":80,"protocol":"TCP","targetPort":8082}],"selector":{
       "k8s-app":"heapster"},"sessionAffinity":"None","type":"NodePort"},"status":{
       "loadBalancer":{}}}
      creationTimestamp: 2018-07-25T03:22:01Z
      labels:
        kubernetes.io/name: heapster
        plugin: heapster
      name: heapster
      namespace: kube-system
      resourceVersion: "789489505"
      selfLink: /api/v1/namespaces/kube-system/services/heapster
      uid: e56886a2-8fb9-11e8-acd2-5254171bf8db
    spec:
      clusterIP: 10.3.129.117
      externalTrafficPolicy: Cluster
      ports:
      - nodePort: 30003
        port: 80
        protocol: TCP
        targetPort: 8082
      selector:
        k8s-app: heapster
      sessionAffinity: None
      type: NodePort
    status:
      loadBalancer: {}

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

**LoadBalancer 方式**

这种方式主要是利用其他第三方的LB暴露服务的，谷歌或者亚马逊的LB等等

kind: Service
    apiVersion: v1
    metadata:
      name: my-service
    spec:
      selector:
        app: MyApp
      ports:
      - protocol: TCP
        port: 80
        targetPort: 9376
      clusterIP: 10.0.171.239
      loadBalancerIP: 78.11.24.19
      type: LoadBalancer
    status:
      loadBalancer:
        ingress:
        - ip: 146.148.47.155

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

**ExternalName 方式**

这种方式主要是通过CNAME实现的，在kubernetes 1.7.x以及以上才支持这种方式，例如

kind: Service
    apiVersion: v1
    metadata:
      name: my-service
      namespace: prod
    spec:
      type: ExternalName
      externalName: my.database.example.com

访问时，kube-dns服务直接解析到指定的Cname`my.database.example.com`这个域名上

参考：[Publishing services - service types][]

[Publishing services - service types]: https://kubernetes.io/docs/concepts/services-networking/service