FDRMOVE target volume initialization

The target volumes must be prepared. We recommend that you create brand-new target volumes, initializing them with appropriate sized VTOCs for the number of data sets you expect to place on the volumes.

FDRMOVE includes a volume initialization utility, FDRINITV, that can easily initialize many target volumes with simple control statements. Although volume initialization can be done with the IBM ICKDSF utility, it requires coding an INIT statement for each volume to be processed. FDRINITV is much more convenient.

Here is a sample FDRINITV job to initialize many 3390-27 DASD volumes very quickly.

//FDRINITV EXEC PGM=FDRINITV,REGION=0M//STEPLIB DD DISP=SHR,DSN=fdrpas.loadlib//SYSPRINT DD SYSOUT=*//FDRSUMM DD SYSOUT=*//SYSUDUMP DD SYSOUT=*//SYSIN DD * INITVTOC TYPE=FULL,VARYON=AFTER,CHECKTARGET=YES MOUNT INITUNIT=21C*,CHANGEVOL=DB////, VTOCLOC=15,VTOCSIZE=750/*

FDRINITV is based on the EMPTYVTOC function of FDRERASE, except that the main statement is INITVTOC instead of EMPTYVTOC. For more information on the options available with FDRINITV, please read the information on EMPTYVTOC Statement.

In the FDRINITV example above, the DASD volumes must be offline before FDRINITV starts but VARYON=AFTER varies them online after initialization. DASD volumes 21C0-21CF are initialized as non SMS-managed volumes, with volume serials from DB0000 to DB0015. VTOCLOC=15 starts the VTOC at cylinder 1 and VTOCSIZE=750 causes it to occupy 50 full cylinders (750 tracks). FDRINITV calculates an appropriate size for the VTOCIX based on the VTOC size. CHECKTARGET=YES verifies that the volumes to be initialized do not contain any data sets.

To initialize SMS-managed volumes, add the STORAGEGROUP operand to the MOUNT statement, for example,

MOUNT INITUNIT=21C*,CHANGEVOL=DB////,VTOCLOC=15,VTOCSIZE=750, STORAGEGROUP

After initializing the SMS-managed volumes, you must use ISMF to add those volumes to a storage group. We recommend that this be the same storage group used by the input data sets to be moved with FDRMOVE.

There are 50 Data Set Control Blocks (DSCBs) per track on a 3390 VTOC; each DSCB describes one data set or VSAM component. Extra DSCBs are required for data sets over three extents. Therefore, a 30 track (two cylinder) VTOC holds about 400 data sets/components. A 750 track VTOC holds over 35,000 data sets. The VTOCIX needs to be only fraction of the size of the VTOC. Please read an appendix in the IBM Device Support Facilities (ICKDSF) User’s Guide and Reference (GC35-0033) for more information on VTOC and VTOCIX sizes.

If you are initializing a smaller DASD (for example, 3390-9) or a larger DASD (for example, 3390-54) you can adjust the VTOC size appropriately. If you expect the volume to hold only a few large data sets, you may want to make the VTOC smaller.

It is possible to use FDRPAS to move some volumes to the target DASD volumes and then use FDRMOVE to add data sets from other volumes to fill up the free space on the larger DASD. However, the VTOCs on the volumes moved with FDRPAS must be large enough to accommodate the extra data sets. The example (see Consolidate Volumes with FDRPAS and FASTMOVE) shows how to consolidate volumes with FDRPAS and FDRMOVE with notes on checking VTOC sizes and expanding VTOCs. FDRPAS is recommended only for moving volumes containing data sets that FDRMOVE cannot handle, such as catalogs (see FDRMOVE Special Considerations).