Re-executing steps

The idea of a re-executable step is different from the one of a restartable step, as it can be considered a subset of a restartable step:

• A restartable step is always a re-executable step.
• A re-executable step might be restartable or not.

A step can be re-executed if it does not refer to any data sets or if it includes a DDNAME that is listed in the parameter DDALWAYS (in the RCLOPTS initialization statement). Otherwise, if the step does refer to a data set, it can be re-executed if the data set meets one of the three following conditions:

• The disposition type is NEW. With JES you cannot execute or restart from a step that has a back reference (REF=) in the VOL parameter to a previous step that has not been executed. In HCL Workload Automation for Z you cannot use this type of restart.
• The disposition type is MOD, and the data set is allocated before running the step, unless the step never ran in the previous job runs (flushed or NORUN).
• The disposition type is OLD or SHR, and the data set is either of the following:
  • Allocated before running this step.
  • Available and has one of the following characteristics:
    • The normal disposition is UNCATLG.
    • The data set is not allocated in the JCL before this step.
    • The data set is cataloged before running this step.
    • The data set has been cataloged at the end of the previous run and no catalog action is taken in any of the steps that follow.