As per CA Disk User Guide, Chapter 5: Reports, section General Information:
The catalog-based reports are formatted identically to the VTOC-based reports; however, the results can differ for multivolume data sets.
VTOC-based reports will show only the volumes specified in the selection criteria, whereas the catalog-based reports will show all volumes the data set resides on even if the primary volume is the only volume selected.
Here some MVD report samples to illustrate the two options:
Given a multi-volume Datei ABC.MULTIVOL located on the volumes VOL011, VOL012, VOL013 and VOL014, also in this volume sequence:
1) The VTOC based report via SCAN REALVOLS does only show the data set parts from selected volumes, for example from VOL012 and VOL013:
2) A catalog based report like
or (even quicker):
finds all 4 parts of the multi-volume data set.
3) However, all parts of the multi-volume data set are only found if the primary volume of the multi-volume data set is in the selection list.
That means for our example data set, if the primary volume (VOL011) of the sample data set is not selected, the data set will not be selected at all: