Question

我有3个节点的kubernetes，主机名分别为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

我定义了3个大小为100M的本地持久卷，它们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>是以下主机之一：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>

应用了三种此类Yaml后，我将得到以下信息：

$ 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容器来写入文件。该文件应位于本地永久卷上。我将其部署为具有1个副本的状态集，并通过statefulset的volumeClaimTemplates映射卷：

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

批量声明似乎已经成功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，吊舱处于挂起状态：

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

如果我们进行描述，我们会看到以下错误：

$ 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.

您能帮助我找出问题所在吗？为什么不能只创建吊舱？

Answer 1

似乎PV可用的一个节点有一个污点，您的StatefulSet无法忍受。

Answer 2

我的情况与上述情况非常相似，并观察到相同的症状（节点相似性冲突）。就我而言，问题是我有2个卷连接到2个不同的节点，但试图在1个容器中使用它们。

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。一旦将Pod设置为使用同时在一个节点上的卷，就不再有问题了。

将statefulset绑定到本地持久卷-卷节点相似性冲突错误

2 个答案: