Introduction to the DFSMSdss component of DFSMS

DFSMSdss is a direct access storage device (DASD) data and space management tool. DFSMSdss works on DASD volumes only in the z/OS® environment.

You can use DFSMSdss to do the following tasks:
  • Copy and move data sets between volumes of like and unlike device types. Like devices have the same track capacity and number of tracks per cylinder (for example, 3380 Model D, Model E, and Model K). In contrast, unlike DASD have different track capacities (for example, 3380 and 3390), a different number of tracks per cylinder, or both.
  • Dump and restore z/OS UNIX files, data sets, entire volumes, or specific tracks
  • Convert data sets and volumes to and from storage management subsystem (SMS) management
  • Compress partitioned data sets
  • Release unused space in data sets
  • Reduce or eliminate DASD free space fragmentation by consolidating free space on a volume, or consolidating data set extents.