When data is created you can select an appropriate retention method for a volume set. The basic choice is either VRSEL retention method or EXPDT retention method. See the "Retention Methods" topic in z/OS DFSMSrmm Managing and Using Removable Media, SC23-6873 for considerations when deciding which retention method to use.

A system-wide default retention method can be specified in parmlib. This is applied by default to volumes added to DFSMSrmm and for each new volume set created during OCE. In addition, for each new volume set created during OCE, you can use installation exit EDG_EXIT100 to select the retention method.

Volumes and data sets retained by the EXPDT retention method are not subject to VRSEL. Only inventory management expiration processing determines whether the volumes are retained or expired. Volume sets retained by the EXPDT retention method can be retained by VOLUME, SET, or FIRSTFILE. Return to scratch is attempted in a single run of inventory management EXPROC processing, as if the scratchimmediate VRS release option had been used for these volumes. Any movement of EXPDT managed volumes must be done with a manual move.

Volumes and data sets retained by the VRSEL retention method are processed by VRSEL processing, which tries to match data sets and volumes to vital record specifications, and if a match is found, to determine whether the data sets or volumes are to be retained by vital record specifications. When the volume is no longer retained by any vital record specification, it is a subject for expiration processing. With vital record specifications and vital record specification chains, you can also specify movement policies to automate the movement of your volumes through locations.