Full-volume restore from a dump copy

Full-volume restore is the process of recovering the entire physical contents of a volume. Full-volume restore, an alternative to the DFSMShsm volume recover function, invokes Data Facility Data Set Services (DFSMSdss) to perform full-volume restores. DFSMShsm uses the dump volumes of a dump copy as input to a DFSMSdss full-volume restore request. If the dump copy starts in file 2 or beyond on a stacked dump tape, DFSMShsm supplies the file block ID for high-speed positioning to the start of the dump copy. The following commands can be used to request a full-volume restore: 
RECOVER * TOVOLUME(original_volser) UNIT(unittype) -
   FROMDUMP

RECOVER * TOVOLUME(original_volser) UNIT(unittype) -
   FROMDUMP DATE(date)

RECOVER * TOVOLUME(original_volser) UNIT(unittype) -
   FROMDUMP(DUMPVOLUME(tape_volser))

RECOVER * TOVOLUME(original_volser) UNIT(unittype) -
   FROMDUMP(DUMPCLASS(class))

RECOVER * TOVOLUME(original_volser) UNIT(unittype) -
   FROMDUMP(DUMPCLASS(class)) DATE(yyyy/mm/dd) -

RECOVER * TOVOLUME(original_volser) UNIT(unittype) -
   FROMDUMP(DUMPGENERATION(dgennum)) -
   TARGETVOLUME(spare_volser)
Note:
  1. The TARGETVOLUME(spare_volser) parameter can be used to supply the restore with a volume that has a volume serial number different from the one that is being restored. This saves you the step of changing the volume serial number (clipping a volume) to the lost volser.
  2. A DFSMSdss restriction is that the original source volume of the full-volume dump must be of the same or similar device type (for example, 3390) as the target volume of the full-volume restore.
  3. For more information, see TARGETVOLUME: Specifying the volume to receive the restored data sets and RECOVER command: Recovering a backup version or dump copy of a data set or a volume.
  4. The VTOC and the volume serial on the target volume may have changed as a result of the command. Before the volume can be accessed on any remote system, the UCB must be refreshed. The refresh occurs automatically if the volume is online and the device manager REFUCB function is enabled. You enable the REFUCB function through PARMLIB member DEVSUPxx or the MODIFY DEVMAN command. For more information, refer to the description of the REFUCB keyword in z/OS MVS Initialization and Tuning Reference or z/OS MVS System Commands.

The first form of the command restores the volume from the most recent dump copy. However, DFSMShsm must search its records to determine the most recent dump copy for the particular volume. You should not use this form of the command because of the extensive searching required.

The second form of the command narrows the search for the correct dump copy. If you know the date that the volume was dumped to the copy that you want to restore from (either the most recent or some other copy), you can specify the date. Then DFSMShsm searches only for dump copies made on or before the date you have specified.

Similarly, the other forms of the command allow you to narrow the search by specifying:
  • The volumes to which the source volume was dumped
  • The dump class from which the dump volumes are to be taken
  • The dump generation from which the dump volumes are to be taken

When a full-volume restore is requested, DFSMShsm verifies with the tape operator that the dump volumes are available for mounting. If any dump volume is unavailable, the restore fails. Dump volumes can be stored at a location other than the data processing location.

If the volume being restored is an SMS-managed volume and the dump copy being used to restore the volume was made when the volume was not SMS-managed, DFSMShsm fails the command and issues an error message. Likewise, if an attempt is made to restore a non-SMS-managed volume from a dump copy of the volume when it was SMS-managed, DFSMShsm fails the command and issues an error message.

The dump volumes on which the dump copy resides must have a retention period other than NOLIMIT unless the DUMPCLASS or DUMPVOLUME parameter is specified. DFSMShsm assumes the dump volumes are physically available to be mounted when the RECOVER command is issued. DFSMShsm considers any volume with a retention period of NOLIMIT to be physically not available.

To restore an SMS-managed volume, you must have DFSMSdfp installed at the correct level to support SMS, and SMS must be active.

DFSMSdss restores a volume only if the volume is not allocated to another job. If the volume contains a catalog, the catalog address space in a DFSMSdfp environment may have the catalog (and the volume) allocated. To free the volume before starting the restore, do the following:

  1. Issue the F CATALOG,OPEN(volser) command to determine which catalogs on the target volume are allocated.
  2. For each catalog that is open, issue the F CATALOG,UNALLOCATE (catalogname) to cause the catalog address space to close the catalog and deallocate it. When the last catalog on the volume is deallocated, the target volume is also deallocated by the catalog address space.
  3. Issue a D U,,,addr,1 command to ensure that the volume is not allocated by another user.
  4. If the volume is not now marked as allocated, issue the RECOVER command to DFSMShsm.

Related reading

For more information about a DFSMSdss full-volume restore, see z/OS DFSMSdss Storage Administration.