Moving data in an SMS-managed environment

In an SMS-managed environment, ACS routines and VTOC/Data Set Services (VDSS) determine the target volume in an SMS-managed environment.

DFSMSdss moves data sets to different volumes if their storage groups change. However, even if their storage groups do not change, DFSMSdss might move the data sets to a different location on the same volume or to different volumes. Target volumes selected by the user might not be honored.

If a new, empty volume is added to a storage group, data sets moved into that storage group are likely to be placed on that volume.

If a data set’s storage class has the guaranteed-space attribute and the user specifies output volumes, the data set is placed on the SMS volumes specified in the volume list if:

All SMS-managed volumes specified with the OUTDDNAME or OUTDYNAM keyword belong to the same storage group.
The ACS storage group routine assigns the data set to the storage group that contains the specified SMS volumes.

Note: SMS-managed data sets must be cataloged in the standard order of search.

Related reading: For more information about SMS, see z/OS DFSMSdfp Storage Administration.