I have encountered such problem. Clients want to migrate data from namespace A to namespace B. The data is stored in Ceph and managed by ceph csi. The default reclaim policy is delete. So If I want to complete this, I need to change PV’s reclaim policy from delete to retain and then delete pvc. After this, I can generate new pvc binding with the PV by volumeName field. It works if I operate manually. However, the scale is not that small. I want to make this process automatically. However, it causes data loss.

The pseudo-code is as follow:

func Migrate() {    
    pv := getPV()
    oldPVC := getOldPVC(pvcName, namespaceA)
    pv.ReclaimPolicy = "Retain"
    pvConroller.Update(pv)
    for {
        curPV := pvController.GetPV(pvName)
        if curPV.ReclaimPolicy == "Retain" {
            break
        }
        // retry get for loop
    }
    pvcController.Delete(oldPVC)
    ...
    // genetate new pvc and bind
}

Is there any way to confirm deleting pvc operation after pv has been updated by controller rather than just recording in ETCD