kubernetes - 如何获得对我的服务分配给我的部署的NodePort的更多控制？

Question

我有5个副本的部署。全部都有ssh和telnet。它们不应负载均衡。我希望每个人都从5个可预测的列表中进行选择。

这是我的部署

apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp
spec:
  selector:
    matchLabels:
      app: myapp
  replicas: 5
  template:
    metadata:
      labels:
        app: myapp
    spec:
      containers:
      - name: myapp
        image: myapp:1.0
        ports:
        - name: ssh
          protocol: TCP
          containerPort: 22
        - name: telnet
          protocol: TCP
          containerPort: 23

这是我的服务，具有无效的nodePort值，仅供说明。

apiVersion: v1
kind: Service
metadata:
  name: myapp
  labels:
    app: myapp
spec:
  type: NodePort
  ports:
  - name: ssh
    port: 22
    nodePort: [30022, 30122, 30222, 30322, 30422, 30522]
  - name: telnet
    port: 23
    nodePort: [30023, 30123, 30223, 30323, 30423, 30523]

我希望能够完成两件事:

每个pod副本实例仅从[30022、30122、30222、30322、30422、30522]获得ssh端口，并从[30023、30123、30223、30323、30423、30523]获得telnet端口。

获得ssh端口为30022的pod副本实例也获得telnet端口30023。获得ssh端口为30122的pod副本实例获得telnet端口30123，依此类推。

谢谢!

Answer 1

您可以使用StatefulSet代替Deployment:

Like a Deployment, a StatefulSet manages Pods that are based on an identical container spec. Unlike a Deployment, a StatefulSet maintains a sticky identity for each of their Pods. These pods are created from the same spec, but are not interchangeable: each has a persistent identifier that it maintains across any rescheduling.

StatefulSets的特别有用的功能是，您将获得可预测地为每个 pods 生成的唯一标签:

When the StatefulSet controller creates a Pod, it adds a label, statefulset.kubernetes.io/pod-name, that is set to the name of the Pod. This label allows you to attach a Service to a specific Pod in the StatefulSet. [source]

然后，您将创建 五个不同的服务，每个 pods 一个，格式如下:

apiVersion: v1
kind: Service
metadata:
  name: myapp-${n}
  labels: { ... } # whatever you want
spec:
  type: NodePort
  selector: 
    statefulset.kubernetes.io/pod-name: myapp-${n} # assuming you keep the name
                                                   # "myapp" and just switch kind
                                                   # from Deployment to StatefulSet
  ports:
  - name: ssh
    port: 22
    nodePort: 30${n}22
  - name: telnet
    port: 23
    nodePort: 30${n}23

通过 ${n}将 0替换为 4。