Fallback unload

You can use the FABHURG1 unload utility to restore HDAM or HIDAM databases that were migrated to PHDAM or PHIDAM.

The procedure for the fallback unload of HALDBs is described in IMS Database Administration. The FABHURG1 unload utility can be used as a replacement of the IMS HD Reorganization Unload utility (DFSURGU0) in the fallback scenario. Note, however, the following considerations:

  • FABHURG1 can be used for the fallback unload of PHDAM or PHIDAM databases.
  • FABHURG1 does not support the fallback unload of partitioned secondary indexes (PSINDEXs). PSINDEXs must be unloaded by the IMS HD Reorganization Unload utility.
  • Start of changeFABHFSU does not support the fallback unload.End of change


Specify the FALLBACK control statement in SYSIN DD to unload a PHDAM or PHIDAM database for a fallback. For more information about the control statement, see FALLBACK control statement.

When fallback unload is designated, FABHURG1 must be executed in the ULU region.

JCL example for fallback unload

To create an unloaded data set that can be used for a fallback of a PHDAM or PHIDAM database, you can use the JCL shown in the following figure. The example uses the IBM®-supplied FABHULU cataloged procedure.

Assume that the database is a PHDAM database and consists of three data set groups.

The DBRC=Y option must be specified on the EXEC statement. The unloaded data set is defined by the SYSUT2 DD statement. You do not need to code any DD statements for database data sets, because all data sets are dynamically allocated by HSSR Engine.

The FALLBACK control statement is specified in the SYSIN DD, which indicates that this is a fallback unload.

//SYSIN    DD *
//            VOL=SER=FBKDS1