hi guys,I met a problem while creating "New Domain" iso/nfs storage,it prints "Error while executing action New NFS Storage Domain: Storage domain remote path not mounted"  and  the error code is 477.anyone can give some hits?

 I followed the "http://wiki.ovirt.org/wiki/Troubleshooting_NFS_Storage_Issues" and find that the vdsm user can't now use mount."mount: only root can do that"

the version I use:
oVirt Engine Version: 3.1.0-2.fc17 
oVirt Node Hypervisor 2.5.4-0.1.fc17 

the error log:
2012-11-08 09:15:00,004 INFO  [org.ovirt.engine.core.bll.AutoRecoveryManager] (QuartzScheduler_Worker-77) Checking autorecoverable storage domains done
2012-11-08 09:17:28,920 WARN  [org.ovirt.engine.core.bll.GetConfigurationValueQuery] (ajp--0.0.0.0-8009-2) calling GetConfigurationValueQuery (StorageDomainNameSizeLimit) with null version, 
using default general for version
2012-11-08 09:17:29,333 INFO  [org.ovirt.engine.core.vdsbroker.vdsbroker.ValidateStorageServerConnectionVDSCommand] (ajp--0.0.0.0-8009-3) [7720b88f] START, ValidateStorageServerConnectionVDSCommand(vdsId = 12bcf124-29a4-11e2-bcba-00505680002a, storagePoolId = 00000000-0000-0000-0000-000000000000, storageType = NFS, connectionList = [{ id: 6556c55d-42a4-4dcc-832c-4d8987ebe6bd, connection: 200.200.101.219:/usr/lwq/iso };]), log id: 52777a80
2012-11-08 09:17:29,388 INFO  [org.ovirt.engine.core.vdsbroker.vdsbroker.ValidateStorageServerConnectionVDSCommand] (ajp--0.0.0.0-8009-3) [7720b88f] FINISH, ValidateStorageServerConnectionVDSCommand, return: {6556c55d-42a4-4dcc-832c-4d8987ebe6bd=0}, log id: 52777a80
2012-11-08 09:17:29,392 INFO  [org.ovirt.engine.core.bll.storage.AddStorageServerConnectionCommand] (ajp--0.0.0.0-8009-3) [7720b88f] Running command: AddStorageServerConnectionCommand internal: false. Entities affected :  ID: aaa00000-0000-0000-0000-123456789aaa Type: System
2012-11-08 09:17:29,404 INFO  [org.ovirt.engine.core.vdsbroker.vdsbroker.ConnectStorageServerVDSCommand] (ajp--0.0.0.0-8009-3) [7720b88f] START, ConnectStorageServerVDSCommand(vdsId = 12bcf124-29a4-11e2-bcba-00505680002a, storagePoolId = 00000000-0000-0000-0000-000000000000, storageType = NFS, connectionList = [{ id: 6556c55d-42a4-4dcc-832c-4d8987ebe6bd, connection: 200.200.101.219:/usr/lwq/iso };]), log id: 36cb94f
2012-11-08 09:17:29,656 INFO  [org.ovirt.engine.core.vdsbroker.vdsbroker.ConnectStorageServerVDSCommand] (ajp--0.0.0.0-8009-3) [7720b88f] FINISH, ConnectStorageServerVDSCommand, return: {6556c55d-42a4-4dcc-832c-4d8987ebe6bd=477}, log id: 36cb94f
2012-11-08 09:17:29,658 ERROR [org.ovirt.engine.core.bll.storage.NFSStorageHelper] (ajp--0.0.0.0-8009-3) [7720b88f] The connection with details 200.200.101.219:/usr/lwq/iso failed because of
 error code 477 and error message is: 477
2012-11-08 09:17:29,717 INFO  [org.ovirt.engine.core.bll.storage.AddNFSStorageDomainCommand] (ajp--0.0.0.0-8009-11) [1661aa36] Running command: AddNFSStorageDomainCommand internal: false. En
tities affected :  ID: aaa00000-0000-0000-0000-123456789aaa Type: System
2012-11-08 09:17:29,740 INFO  [org.ovirt.engine.core.vdsbroker.vdsbroker.CreateStorageDomainVDSCommand] (ajp--0.0.0.0-8009-11) [1661aa36] START, CreateStorageDomainVDSCommand(vdsId = 12bcf12
4-29a4-11e2-bcba-00505680002a, storageDomain=org.ovirt.engine.core.common.businessentities.storage_domain_static@4a900545, args=200.200.101.219:/usr/lwq/iso), log id: 50b803a0
2012-11-08 09:17:35,233 ERROR [org.ovirt.engine.core.vdsbroker.vdsbroker.BrokerCommandBase] (ajp--0.0.0.0-8009-11) [1661aa36] Failed in CreateStorageDomainVDS method
2012-11-08 09:17:35,234 ERROR [org.ovirt.engine.core.vdsbroker.vdsbroker.BrokerCommandBase] (ajp--0.0.0.0-8009-11) [1661aa36] Error code StorageDomainFSNotMounted and error message VDSGeneri
cException: VDSErrorException: Failed to CreateStorageDomainVDS, error = Storage domain remote path not mounted: ('/rhev/data-center/mnt/200.200.101.219:_usr_lwq_iso',)
2012-11-08 09:17:35,260 INFO  [org.ovirt.engine.core.vdsbroker.vdsbroker.BrokerCommandBase] (ajp--0.0.0.0-8009-11) [1661aa36] Command org.ovirt.engine.core.vdsbroker.vdsbroker.CreateStorageD
omainVDSCommand return value