MF_UCC11

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

When restarting a job, a cataloged data set is presumed to have an initial disposition of MOD rather than NEW. As a result, any new data is appended to the existing data set.

MR

When MF_UCC11=M, any DISP=NEW dataset will be removed and then recreated when a job is run. Also, when the job is restarted, the DISP=NEW is changed to DISP=MOD.

However, your preference might be that the dataset should not be deleted and recreated when the job is first run but the DISP is changed to MOD only when the job is restarted.

To achieve this behavior, set MF_UCC11=MR. This option provides the same functionality as MF_UCC11=Y except that it changes DISP=NEW to DISP=MOD but only when the job is restarted.

N

JCL job restart functionality is disabled.

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 dataset is DISP=NEW, if the DSORG of the dataset 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 dataset will not be replaced, and the JCLCM0200S error message is issued.