Results of recalling GUARANTEED SPACE VSAM data sets

When DFSMShsm is the data mover, data sets recalled with the GUARANTEED SPACE attribute are normally placed on the volume from which they migrated. Consider the effects on a migrated, multiple-volume VSAM data set. A subsequent recall preserves the volume-to-component relationship that originally existed as long as the data set remains SMS-managed. For a data set in a GUARANTEED SPACE storage class, the relationship includes returning the data set to the same volumes from which it migrated. Thus, if a data set was originally defined with the data component on one volume and the index component on another, a migrate/recall sequence preserves the relationship between the components and the volumes. Similarly, if a key range data set has three key ranges on three separate volumes, the relationship is preserved.

If a volume is specified on the RECALL command, that volume is passed to IMPORT. When the IMPORT function redefines the VSAM data set, the specified volume overrides the volume or volumes from which the data set has been exported. If the specified volume is eligible, the data set is imported to that single volume. If there is not enough space, the recall fails. If the volume is not eligible, another volume may be selected. If the data set resides on multiple volumes when it is migrated, it is recalled to a single volume.