Exporting MODBLKS resource and descriptor definitions to an RDDS

Use the automatic export function or the EXPORT DEFN TARGET(RDDS) command to save your current MODBLKS resource and descriptor definitions to a resource definition data set (RDDS).

When exporting to a system RDDS, all the IMS MODBLKS resource and descriptor definitions must be exported. All definitions in the system RDDS are overwritten with the definitions being exported.
When exporting to a non-system RDDS, all or some of the IMS MODBLKS resource and descriptor definitions can be exported. You can either overwrite the existing definitions with the new definitions or append the new definitions to the end of the data set.
Definitions for IMS resources such as the Fast Path utility (DBF#FPU0) and the IMS defined descriptors (DBFDSRT1, DFSDSDB1, DFSDSPG1, and DFSDSTR1) cannot be exported.

Exporting MODBLKS resource and descriptor definitions with automatic export

Perform the following procedure to set up automatic export of MODBLKS resource and descriptor definitions to an RDDS:

Define two or more system resource definition data sets to IMS by using the RDDSDSN() parameter in the DYNAMIC_RESOURCES section of the DFSDFxxx member in the IMS PROCLIB data set.
If you are using automatic import or automatic export, each IMS system must have its own set of system RDDSs.
Specify AUTOEXPORT=AUTO or AUTOEXPORT=RDDS in the DYNAMIC_RESOURCES section in the DFSDFxxx member of the IMS PROCLIB data set.

Resource and descriptor definitions are exported to the oldest RDDS at checkpoint time if the definitional attributes of one or more resources has changed since the last checkpoint.

XRF considerations:

An XRF active and alternate can be enabled to use autoexport to the IMSRSC repository. The active and alternate must explicitly specify AUTOEXPORT=AUTO or REPO in the DFSDFxxx member. The AUTOEXPORT= and AUTOEXPORT_IMSID= values in the DFSDFxxx members at the active and alternate must be the same because IMS does not validate that the same value is specified for the active and alternate. If they are different, the results are unpredictable.

When AUTOEXPORT_IMSID=THIS_IMS is specified in the DFSDFxxx member, the XRF active and the XRF alternate write the resource definition changes to the repository. When AUTOEXPORT_IMSID=ALL is specified in the DFSDFxxx member and the XRF alternate is defined to the repository, the XRF active writes the resource definition changes to the repository for the XRF alternate as well. The XRF alternate also tries to write the resource definition changes, but because the changes are already in the repository, the write is treated as successful (even though no physical write to the IMSRSC repository is made).

No X'22' map byte X'51' autoexport log record is written on the XRF alternate, because no logger services are available on the XRF alternate.

Exporting MODBLKS resource and descriptor definitions with the EXPORT command

Use the EXPORT DEFN TARGET(RDDS) command to export MODBLKS resource and descriptor definitions to an RDDS.

MODBLKS resource and descriptor definitions are either written to the data set specified by the RDDSDSN() command keyword, or to the system RDDS containing the oldest data. A system RDDS is one of the RDDS data sets that is defined with the RDDSDSN= parameter in the DYNAMIC_RESOURCES section of the DFSDFxxx member of the IMS PROCLIB data set. A system RDDS contains all the MODBLKS resource and descriptor definitions for a single IMS system.