RESTART keyword

The RESTART keyword specifies whether to enable Checkpoint Restart for automatic restart of image copy processing.

Functions that support this keyword
Image Copy function
Statements that support this keyword
GLOBAL statement
Site default option
Supported
Related keyword
None.
Format
Read syntax diagramSkip visual syntax diagramRESTART=N or (Y,COUNT=5)YNC(YC,HASH,COUNT= nn)
Y
Enables both checkpoint and restart. To specify Y, you must supply the checkpoint file with the CHDPTDD DD statement.
N
Does not enable checkpoint restart processing. When the job step ends, the checkpoint file is reset.
C
Enables checkpoint processing but not restart processing.

The following optional parameters can be specified as subparameters for Y or C. These optional parameters are ignored when used with parameter N.

HASH
Specifies whether to run the restart processing based on the type of the pointer error detected by HASH Check.
  • When the detected pointer error is an unidentified error, the restart processing is run.
  • When the detected pointer error is a severe error, the restart processing is not run.
You can check the type of the pointer errors in the Image Copy Process Summary report.
If the HASH subparameter is not specified, pointer errors that are detected by HASH Check are not considered in the restart processing.
COUNT=nn
Specifies the maximum number for restart attempts. nn is a value in the range of 1 - 99. When the number of restart attempts exceeds this value, no more restart processing is done, and the checkpoint file will be reset.
Default value
  • If a valid checkpoint data set is provided with the CHKPTDD DD statement, RESTART=(Y,COUNT=5).
  • If there is no valid checkpoint data set, RESTART=N.
Usage notes
This keyword operates at the job-step level. Multiple image copy job steps require multiple Checkpoint Restart data sets, one for each job step.

In order for a restart to begin, the image copy environment must be precisely the same as the one existing at the time of the checkpoint. If any image copies have been added or subtracted, the restart is invalidated.

When a restart is initiated, all databases or stacks that failed will be image copied again, including any jobs that were restarted previously. DBDSs or stacks which have successfully completed image copies, will be bypassed. The unit of restart is specified by the RSTTYPE keyword and the behavior of the restart processing is specified by the RSTTYPE_STK keyword.

If you want to cancel the restart processing, you must discard the current checkpoint record in the checkpoint file that is specified on the CHKPTDD DD statement. To discard current checkpoint record, you must delete the checkpoint file or run IMS HP Image Copy job with RESTART=C or RESTART=N.
If a severe pointer error is detected in RESTART=(Y,HASH) processing, the database will not be restarted. In this case, you must check the error in the database and, if needed, repair the database. To reprocess the database that had a severe error with the Checkpoint Restart function, you must recreate the checkpoint file with the preceding method.