Binding statefulset to local persistent volumes - volume node affinity conflict 错误

Binding statefulset to local persistent volumes - volume node affinity conflict error

我有 3 节点 kubernetes,主机名是 host_1、host_2、host_3。

$ kubectl get nodes
NAME       STATUS    ROLES     AGE       VERSION
host_1     Ready     master    134d      v1.10.1
host_2     Ready     <none>    134d      v1.10.1
host_3     Ready     <none>    134d      v1.10.1

我已经定义了 3 个大小为 100M 的本地持久卷,映射到每个节点上的本地目录。我使用了以下描述符 3 次,其中 <hostname> 是其中之一:host_1、host_2、host_3:

apiVersion: v1
kind: PersistentVolume
metadata:
  name: test-volume-<hostname>
spec:
  capacity:
    storage: 100M
  volumeMode: Filesystem
  accessModes:
  - ReadWriteOnce
  persistentVolumeReclaimPolicy: Delete
  storageClassName: local-storage
  local:
    path: /opt/jnetx/volumes/test-volume
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchExpressions:
        - key: kubernetes.io/hostname
          operator: In
          values:
          - <hostname>

在应用三个这样的 yaml 之后,我有以下内容:

$ kubectl get pv
NAME                 CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS      CLAIM    STORAGECLASS    REASON    AGE
test-volume-host_1   100M       RWO            Delete           Available            local-storage             58m
test-volume-host_2   100M       RWO            Delete           Available            local-storage             58m
test-volume-host_3   100M       RWO            Delete           Available            local-storage             58m

现在,我有一个非常简单的写入文件的容器。该文件应位于本地持久卷上。我通过 statefulset 的 volumeClaimTemplates 将其部署为具有 1 个副本和映射卷的 statefulset:

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: filewriter
spec:
  serviceName: filewriter
  ...
  replicas: 1
  template:
    spec:
      containers:
        - name: filewriter
          ...
          volumeMounts:
          - mountPath: /test/data
            name: fw-pv-claim
  volumeClaimTemplates:
  - metadata:
      name: fw-pv-claim
    spec:
      accessModes:
      - ReadWriteOnce
      storageClassName: local-storage
      resources:
        requests:
          storage: 100M

卷声明似乎已正确创建并绑定到第一台主机上的 pv:

$ kubectl get pv
NAME                 CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS      CLAIM                              STORAGECLASS    REASON    AGE
test-volume-host_1   100M       RWO            Delete           Bound       default/fw-pv-claim-filewriter-0   local-storage             1m
test-volume-host_2   100M       RWO            Delete           Available                                      local-storage             1h
test-volume-host_3   100M       RWO            Delete           Available                                      local-storage             1h

但是,pod 挂起在 Pending 状态:

$ kubectl get pods
NAME                         READY     STATUS    RESTARTS   AGE
filewriter-0                 0/1       Pending   0          4s

如果我们描述,可以看到如下错误:

$ kubectl describe pod filewriter-0
Name:           filewriter-0
...
Events:
  Type     Reason            Age              From               Message
  ----     ------            ----             ----               -------
  Warning  FailedScheduling  2s (x8 over 1m)  default-scheduler  0/3 nodes are available: 1 node(s) had taints that the pod didn't tolerate, 2 node(s) had volume node affinity conflict. 

你能帮我找出问题所在吗?为什么它不能只创建 pod?

似乎 PV 可用的一个节点存在您的 StatefulSet 无法容忍的污点。

我遇到了与上述情况非常相似的情况,并观察到相同的症状(节点关联冲突)。在我的例子中,问题是我有 2 个卷连接到 2 个不同的节点,但试图在 1 个 pod 中使用它们。

我通过使用 kubectl describe pvc name-of-pvc 并注意到 selected-node 注释检测到了这一点。一旦我将 pod 设置为使用同时位于一个节点上的卷,我就不再有问题了。