Changing the WADS mode from single to dual

You can change the write-ahead data set (WADS) mode from single to dual. The WADS can be dynamically allocated and deallocated.

To reflect the new mode for WADSs, you must update the following parameters:

  • Skeletal JCL for the Log Recovery utility (LOGCLJCL member).
  • LOGGER section of the DFSDFxxx member of the IMS.PROCLIB data set (WADSDEF statement).
  • All recovery procedures implemented to recover WADS errors or to close unclosed OLDSs using WADS.

Procedure

  1. Shut down IMS.
  2. Allocate new WADS.
  3. Define a DFSMDA member.
  4. Add DD statement in IMS JCL, if necessary.
  5. Update WADSDEF specification in the LOGGER section of the DFSDFxxx member of IMS.PROCLIB.
  6. Modify operating procedures.
  7. Restart IMS with FORMAT WADS keywords.