Specifying system initialization parameters before startup

You usually specify the system initialization parameters that CICS® is to use in the following ways, before starting CICS.

Procedure

  • In the system initialization table, loaded from a library in the STEPLIB concatenation of the CICS startup procedure
  • In the PARM parameter of the EXEC PGM=DFHSIP statement of the CICS startup procedure
  • In the SYSIN data set defined in the startup procedure, but only if SYSIN is coded in the PARM parameter.

Results

The system initialization parameters are processed in the order outlined above, with later system initialization parameter values overriding those specified earlier.

Example

For example, if your CICS startup procedure specifies: 
//INITCICS  EXEC PGM=DFHSIP,REGION=&REG,
//        PARM=('SYSIDNT=HTH1,SIT=6$,SYSIN,CN')
//*
//SYSIN    DD DISP=SHR,DSN=&libpfx..CICSH###.SYSIN(CICS&CLONE)
CICS uses system initialization parameters from the following sources, with later system initialization parameters overriding earlier ones:
  1. The system initialization table, DFHSIT6$, from the STEPLIB concatenation.
  2. The member CICSH### of the CICSTS53.CICS.CICSH###.SYSIN data set.
  3. The system console.

What to do next

In particular, you can specify a new value for the START system initialization parameter.