Hi folks, I'm already searching on internet and any related documentation with ovirt, but i'm still facing the problem. I've 3 hosts and 1 storage using netapp. After create new LUN and deleting the new one. The Data Centers is down, but VM guests still running. Step to reproduce : 1. Create new LUN. 2. Attach new LUN to existing iscsi storage data (master) 3. The space on the existing iscsi storage would be increase 4. Remove the new LUN from existing iscsi storage 5. Storage domain would be Non-Responsive I've already reboot the rhev-m and also rhev-host. But the Data Centers status is still Non-Responsive. Below the related log : engine.log 2015-03-02 07:55:47,884 WARN [org.ovirt.engine.core.bll.storage.ExtendSANStorageDomainCommand] (ajp-/127.0.0.1:8702-4) [70555e6d] CanDoAction of action ExtendSANStorageDomain failed. Reasons:VAR__TYPE__STORAGE__DOMAIN,VAR__ACTION__EXTEND,ERROR_CANNOT_EXTEND_CONNECTION_FAILED,$lun 2015-03-02 08:05:35,214 ERROR [org.ovirt.engine.core.vdsbroker.vdsbroker.SpmStatusVDSCommand] (DefaultQuartzScheduler_Worker-5) [241bd724] Failed in SpmStatusVDS method 2015-03-02 08:05:35,214 ERROR [org.ovirt.engine.core.vdsbroker.vdsbroker.SpmStatusVDSCommand] (DefaultQuartzScheduler_Worker-5) [241bd724] Error code GeneralException and error message VDSGenericException: VDSErrorException: Failed to SpmStatusVDS, error = [Errno 19] Could not find dm device named `unknown device` 2015-03-02 08:05:35,214 ERROR [org.ovirt.engine.core.vdsbroker.vdsbroker.SpmStatusVDSCommand] (DefaultQuartzScheduler_Worker-5) [241bd724] Command SpmStatusVDS execution failed. Exception: VDSErrorException: VDSGenericException: VDSErrorException: Failed to SpmStatusVDS, error = [Errno 19] Could not find dm device named `unknown device` 2015-03-02 08:05:49,332 ERROR [org.ovirt.engine.core.vdsbroker.irsbroker.IrsBrokerCommand] (DefaultQuartzScheduler_Worker-92) [65ea552c] SPM Init: could not find reported vds or not up - pool:ISCSI_DATA_CENTER vds_spm_id: 2 Thanks.