Multivolume data sets

If you do not specify SELECTMULTI, all volumes must be included in DDNAME or DYNAM volume lists.

If you specify input volumes (with either the DDNAME or DYNAM volume list), a data set is selected based on the following criteria:

When you either specify SELECTMULTI(ALL) or specify input volumes without specifying the SELECTMULTI keyword, all of the volumes that contain a part of the non-VSAM data set or VSAM base cluster must be in the volume list.
When you specify SELECTMULTI(ANY), any part of the non-VSAM data set or VSAM base cluster can be on a volume in the volume list.
When you specify SELECTMULTI(FIRST), the volume list must include the volume that contains either the first part of the non-VSAM data set or the primary data component of the base cluster for a VSAM sphere.

Multivolume data sets are not eligible for conversion if any part of the data set resides on volumes that:

Do not have indexed VTOCs
Are not defined in an SMS storage group
Are defined to a different storage group
Are not permanently mounted and online

If the previous requirements are satisfied, DFSMSdss verifies that all the volumes on which the data set resides:

Are permanently mounted and online
Have indexed VTOCs
Are defined to the same storage group

If all these criteria are met, the data set is converted to SMS management.

Note:

If SELECTMULTI(FIRST) or SELECTMULTI(ANY) is specified, volumes not specified in the DDNAME or DYNAM volume lists are put in the INITIAL state following a successful conversion of the data set to SMS (unless the volume is already in the INITIAL or SMS state.)
If SELECTMULTI is not specified or if SELECTMULTI(ALL) is specified, volumes not specified in the DDNAME or DYNAM volume lists are not put in the INITIAL state.

DFSMSdss cannot determine whether or not a volume being converted is a candidate volume for one or more data sets in the system. If such a volume is converted, DFSMSdss cannot ensure consistent conversion for all of the volumes of the data set (or sets) for which the volume is a candidate. This can result in a data set having both SMS-managed and non-SMS-managed volumes in its volume list, which can cause the data set to become unusable.

To avoid this situation when performing CONVERTV operations, if you specify any volume of a multivolume data set in the list of volumes to be converted, ensure that you also include at least one of the primary volumes of the data set. This allows DFSMSdss to ensure that all of the volumes of the data set are converted consistently.