根据K8S官方文档:
我已经创建了一个带有RWO访问模式的持久卷。我已经应用了PVC:
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
name: readwriteonce-test
spec:
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 8Gi
storageClassName: ""
和部署:
apiVersion: apps/v1beta2
kind: Deployment
metadata:
name: test-deployment
spec:
selector:
matchLabels:
app: test-deployment
replicas: 3
template:
metadata:
labels:
app: test-deployment
spec:
containers:
- name: test-pod
image: "gcr.io/google_containers/busybox:1.24"
command:
- "/bin/sh"
args:
- "-c"
- "rm -R /data/*; while :; do ls /data/; name=$(date '+%s'); echo \"some data in file ${name}\" >> \"/data/${name}.txt\" ; sleep 10; cat \"/data/${name}.txt\"; done"
imagePullPolicy: IfNotPresent
volumeMounts:
- mountPath: /data
name: test-volume
restartPolicy: Always
volumes:
- name: test-volume
persistentVolumeClaim:
claimName: readwriteonce-test
持续体积:
Name: readwriteonce-test
Labels: volume-name=readwriteonce-test
Annotations: kubectl.kubernetes.io/last-applied-configuration:
{"apiVersion":"v1","kind":"PersistentVolume","metadata":{"annotations":{},"labels":{"volume-name":"readwriteonce-test"},"name":"readwriteo...
Finalizers: [kubernetes.io/pv-protection]
StorageClass:
Status: Bound
Claim: ***/readwriteonce-test
Reclaim Policy: Retain
Access Modes: RWO
VolumeMode: Filesystem
Capacity: 8Gi
Node Affinity: <none>
Message:
Source:
Type: NFS (an NFS mount that lasts the lifetime of a pod)
Server: ***.efs.eu-west-1.amazonaws.com
Path: /readwriteonce-test
ReadOnly: false
Events: <none>
问题是:
谁能解释我，为什么这样的配置没有错误？如您所见，每个Pod已安装在不同的节点上。每个 Pane 都可以查看其他 Pane 创建的文件。
screenshot
最佳答案
我只能确认，使用基于EFS的持久卷(在PVC请求规范中动态创建)基于EFS的持久卷时，我与您在测试EKS集群上具有相同的观察结果。
如下所示，我可以从两个不同的Pod(分别安排在不同的节点上)同时写入同一文件:
Hello from test-deployment-6f954f9f67-ljghs at 1583239308 on ip-192-168-68-xyz.us-west-2.compute.internal node
Hello from test-deployment-6f954f9f67-bl99s at 1583239308 on ip-192-168-49-abc.us-west-2.compute.internal node
相反，我宁愿期待类似的行为*，例如在其他PV类型支持所有类型的accessMode(RWO，RWX，ROX)的情况下:
Warning FailedAttachVolume 103s attachdetach-controller Multi-Attach error for volume "pvc-badb4724-5d5a-11ea-8395-42010aa80131"
Multi-Attach error for volume "pvc-badb4724-5d5a-11ea-8395-42010aa80131" Volume is already used by pod(s) test-deployment-xyz-...
*在调度程序尝试使用同一PV调度Pod的第二个副本时发生。
我认为这是基于NFS的存储的本质，它是EFS-provisioner的基础存储类型。
似乎我们不是唯一在那件事上理解官方文档有问题的人，请检查这些开放的github问题:#18714，#60903。
关于kubernetes - Kubernetes PersistentVolumes访问模式，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/60420095/