[Users] Exports : many success, one failure

Hi, I was NFS-exporting many VMs from a 3.1 (iscsi) to a 3.3 (iscsi) oVirt and it was running fine. On a linux VM with 2 disks, I see the export process smoothly filling up the NFS tree. When its seems to reach the data expected size, the web gui tells me the export has failed. The engine.log shows this, which does not help me much. 2013-10-14 16:23:12,603 ERROR [org.ovirt.engine.core.bll.SPMAsyncTask] (QuartzScheduler_Worker-82) BaseAsyncTask::LogEndTaskFailure: Task f931d5cf-1b73-408a-8149-2c4bada047ec (Parent Command ExportVm, Parameters Type org.ovirt.engine.core.common.asynctasks.AsyncTaskParameters) ended with failure: -- Result: cleanSuccess -- Message: VDSGenericException: VDSErrorException: Failed to HSMGetAllTasksStatusesVDS, error = low level Image copy failed, -- Exception: VDSGenericException: VDSErrorException: Failed to HSMGetAllTasksStatusesVDS, error = low level Image copy failed There is still plenty of disk space on the nfs export domain. Network has not been interrupted or whatever. There are snapshots but I checked the collapse box when exporting. What should I look at? -- Nicolas Ecarnot