DSS uses different Volume Manager so you will not be able to use the same Logical Volumes that originally was created from the iSCSI Enterprise product. You will need to back up your data then install the DSS then create new Logical Volumes (iSCSI Volumes) then restore data onto the new DSS Logical Volumes. Currently all iSCSI-R3 and DSS will perform this but not the iSCSI Enterprise to DSS.