Redis Pods无法加入Redis集群

Question

我想在Kubernetes中创建6个节点的Redis集群。我正在使用 Minikube 运行 kubernetes 。

以下是我创建6节点群集的实现。

kind: StatefulSet
metadata:
  generation: 1
  labels:
    app: demo-app
  name: demo-app
  namespace: default
spec:
  podManagementPolicy: OrderedReady
  replicas: 6
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      app: demo-app
  serviceName: ""
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: demo-app
    spec:
      containers:
      - command:
        - redis-server
        - --port 6379
        - --cluster-enabled yes
        - --cluster-node-timeout 5000
        - --appendonly yes
        - --appendfilename appendonly-6379.aof
        image: redis:latest
        imagePullPolicy: Always
        name: demo-app
        resources: {}
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
        volumeMounts:
         - name: redis-pvc
           mountPath: /var
      - image: nginx:1.12
        imagePullPolicy: IfNotPresent
        name: redis-exporter
        resources: {}
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
      dnsPolicy: ClusterFirst
      restartPolicy: Always
      schedulerName: default-scheduler
      securityContext: {}
      terminationGracePeriodSeconds: 30
  updateStrategy:
    rollingUpdate:
      partition: 0
    type: RollingUpdate

  volumeClaimTemplates:
    - metadata: 
        name: redis-pvc
      spec: 
          accessModes: 
           - ReadWriteOnce
          resources:
             requests:
                 storage: 1Gi

创建有状态集之后，我将从一个Pod内部执行redis create cluster命令。

 redis-cli --cluster create 172.17.0.4:6379 172.17.0.5:6379  172.17.0.6:6379  172.17.0.7:6379  172.17.0.8:6379  172.17.0.9:6379 --cluster-replicas 1

这些都是pod的ips。有了这个，我就能启动集群了。但是一旦我手动删除使用

kubernetes delete pod <podname>

例如，删除IP地址为172.17.0.6:6379的Redis节点（假设该节点为主节点），删除Redis集群后的状态为：

127.0.0.1:6379> cluster nodes
1c8c238c58d99181018b37af44c2ebfe049e4564 172.17.0.9:6379@16379 slave 4b75e95772887e76eb3d0c9518d13def097ce5fd 0 1579496695000 6 connected
96e6be88d29d847aed9111410cb0f790db068d0e 172.17.0.8:6379@16379 slave 0db23edf54bb57f7db1e2c9eb182ce956229d16e 0 1579496696596 5 connected
c8be98b16a8fa7c1c9c2d43109abafefc803d345 172.17.0.7:6379@16379 master - 0 1579496695991 7 connected 10923-16383
0db23edf54bb57f7db1e2c9eb182ce956229d16e 172.17.0.4:6379@16379 myself,master - 0 1579496694000 1 connected 0-5460
4daae1051e6a72f2ffc0675649e9e2dad9430fc4 172.17.0.6:6379@16379 master,fail - 1579496680825 1579496679000 3 disconnected
4b75e95772887e76eb3d0c9518d13def097ce5fd 172.17.0.5:6379@16379 master - 0 1579496695000 2 connected 5461-10922

一段时间后更改为：

127.0.0.1:6379> cluster nodes
1c8c238c58d99181018b37af44c2ebfe049e4564 172.17.0.9:6379@16379 slave 4b75e95772887e76eb3d0c9518d13def097ce5fd 0 1579496697529 6 connected
96e6be88d29d847aed9111410cb0f790db068d0e 172.17.0.8:6379@16379 slave 0db23edf54bb57f7db1e2c9eb182ce956229d16e 0 1579496696596 5 connected
c8be98b16a8fa7c1c9c2d43109abafefc803d345 172.17.0.7:6379@16379 master - 0 1579496698031 7 connected 10923-16383
0db23edf54bb57f7db1e2c9eb182ce956229d16e 172.17.0.4:6379@16379 myself,master - 0 1579496697000 1 connected 0-5460
4daae1051e6a72f2ffc0675649e9e2dad9430fc4 :0@0 master,fail,noaddr - 1579496680825 1579496679000 3 disconnected
4b75e95772887e76eb3d0c9518d13def097ce5fd 172.17.0.5:6379@16379 master - 0 1579496697028 2 connected 5461-10922

当redis集群提供自动故障转移，但是pod的redis无法自动加入集群吗？

还是我应该手动将该吊舱加入集群？

Answer 1

我已经解决了这个问题，并使用此状态集yaml创建了redis集群。问题是我没有在持久卷中装入 集群配置
文件。群集配置文件包含其他节点的位置。现在，群集配置文件将在Pod重新启动后持续存在。

由于redis集群适用于八卦协议。它只需要一个活动节点即可获得整个集群的配置。

现在，有状态集的最终配置为：

apiVersion: apps/v1
kind: StatefulSet
metadata:
  generation: 1
  labels:
    app: demo-app
  name: demo-app
  namespace: default
spec:
  podManagementPolicy: OrderedReady
  replicas: 6 
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      app: demo-app
  serviceName: ""
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: demo-app
    spec:
      containers:
      - command:
        - redis-server
        - --port 6379
        - --cluster-enabled yes
        - --cluster-node-timeout 5000
        - --appendonly yes
        - --cluster-config-file /var/cluster-config.conf
        - --appendfilename appendonly-6379.aof
        image: redis
        imagePullPolicy: Always
        name: demo-app
        resources: {}
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
        volumeMounts:
         - name: redis-pvc
           mountPath: /var
      - image: nginx:1.12
        imagePullPolicy: IfNotPresent
        name: redis-exporter
        resources: {}
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
      dnsPolicy: ClusterFirst
      restartPolicy: Always
      schedulerName: default-scheduler
      securityContext: {}
      terminationGracePeriodSeconds: 30
  updateStrategy:
    rollingUpdate:
      partition: 0
    type: RollingUpdate

  volumeClaimTemplates:
    - metadata: 
        name: redis-pvc
      spec: 
          accessModes: 
           - ReadWriteOnce
          resources:
             requests:
                 storage: 1Gi

我所做的唯一更改是在启动redis-server时添加了 --cluster-config-file /var/cluster-
config.conf
参数。