GDG Limit Change

Server Enterprise Edition 6.0 WrapPack 2, and subsequent software releases change the GDG-LIMIT value for Generation Datasets.

After you install the WrapPack or new software releases that include this change, the GDG-LIMIT value conversion is handled automatically. The GDG-LIMIT values are changed over time from the old pic 99 format to the new comp field, as individual catalog records are accessed and updated.

However, if you revert to a previous release, the new-format System Catalog is not readable by the old version of the product. If you revert to a previous release, you can revert the System Catalog so that the system can use it.

To revert the catalog to GDG_LIMIT 99:

1. Backup your system catalog.
2. Run the catalog scan utility mfcatrvt with no parameters.

   This identifies all GDGs where the LIMIT is greater than 99, or has been cycled more than 99 times.

3. Run the catalog revert utility mfcatrvt with the command line parameter REVERT.

   This changes the comp value of the GDG-LIMIT field back to the original PIC 99 representation. Note that the process also converts values greater than 99 back to 99.

When this process completes, the System catalog is readable in older versions of Server Enterprise Edition.