MF_UCC11

Enables emulation of UCC11, the JCL job restart functionality.
Note: This environment variable works independently of the JCL RESTART parameter.

Syntax:

MF_UCC11=Y|YA|M|MA|MR|N

Properties:

Y
When restarting a job with DISP=(NEW,CATLG), it will not result in job failure caused by the data set already being cataloged.
YA
When running a job with DISP=(NEW,CATLG), it will not result in job failure caused by the data set already being cataloged.
M, MA, MR
When restarting a job any data set that has an inital disposition of NEW is changed to MOD. Therefore, data will be appended to the data set if it already exists.
N

MF_UCC11 is not set so a data set with an initial disposition of NEW may cause an error when restarting the job if the data set already exists.

The setting of the MF_UCC11 value can be made on a job-by-job basis using either the JCL user exit, MFJUXIT, or the Advanced Restart Functionality.

Default: N

Comments:

  • When set to Y or YA, if the job uses GDG data sets, the GDG generation is reset to the level used in the previous job, ensuring that the restart will automatically pick up the correct GDG generation.
  • GDG Restart information is usually only written when MF_UCC11=Y, YA or M and ES_JES_RESTART=Y. You can ensure that it is always written by setting ES_JES_RESTART=Y and GDG_RESTART_UCC11_ONLY=N - this will ensure that the restart information is available if a job is restarted at a later date.
  • When restarting a job with restart functionality enabled (that is, values Y, YA, or M), COND Code Processing and IF/THEN logic that is dependent upon COND codes from prior steps that are skipped by the RESTART, will work as expected with no changes to the JCL.
  • When set to YA or M and the disposition of the data set is DISP=NEW, if the DSORG of the data set is defined on the DD Card, it will be checked against the catalog record, if the latter exists. If there is a mismatch, or if the catalog record refers to a GDG base, the data set will not be replaced, and the JCLCM0200S error message is issued.