rancher中grafana nfs持久化，报Migration failed err:disk I/O error 问题

使用nfs-subdir-external-provisioner 

---
image:
repository: xxx
tag: v4.0.2
pullPolicy: IfNotPresent
nfs:
server: "xxx"
path: "/k8s-storage"
mountOptions:
- vers=3
- noresvport
- timeo=600
- retrans=1
- nolock
storageClass:
reclaimPolicy: Retain
archiveOnDelete: false
accessModes: ReadWriteMany
nodeSelector:
node.type: monitor
tolerations:
- effect: NoSchedule
key: node.access
operator: Equal
value: monitor

一定要设置为nolock