Falling back from MODBLKS data sets defined as PDSEs

You can fall back from an IMS system that has MODBLKS data sets defined as partitioned data sets extended (PDSEs) to an earlier version of IMS.

  1. Define the staging MODBLKS data set as a partitioned data set (PDS), if the original staging MODBLKS data set that was defined as a PDS was not saved.
  2. Define the first MODBLKS PDS data set, if the original first MODBLKS PDS data set was not saved.
  3. Define the second MODBLKS PDS data set, if the original second MODBLKS PDS data set was not saved.
  4. Perform a MODBLKS system definition to generate new resource definitions into the staging MODBLKS PDS. Ensure that the number of resources that are generated do not exceed the maximum number that is supported by MODBLKS PDS data sets.
  5. Run the Online Change Copy utility (DFSUOCU0) to copy the staging MODBLKS PDS members to the first MODBLKS PDS.
  6. Shut down IMS.
  7. Change IMS procedure to specify the first MODBLKS PDS data set as the inactive MODBLKS data set.
  8. Warm start IMS with the first MODBLKS PDS as the inactive MODBLKS data set.
  9. Issue the appropriate online change command sequence to make online change to the first differently named MODBLKS PDS data set.
  10. Perform a MODBLKS system definition to generate new resource definitions into staging MODBLKS PDS. Ensure that the number of resources that are generated do not exceed the maximum number that is supported by MODBLKS PDS data sets.
  11. Run the Online Change Copy utility (DFSUOCU0) to copy staging MODBLKS PDS members to the second MODBLKS PDS.
  12. Shut down IMS.
  13. Change IMS procedure to specify the second MODBLKS PDS data set as the inactive MODBLKS data set.
  14. Remove APAR PI90417.
  15. Warm start IMS with the second MODBLKS PDS as the inactive MODBLKS data set.
  16. Issue the appropriate online change command sequence to make online change to the second MODBLKS PDS data set.