The CICS parameter manager domain

In addition to loading the system initialization table at the start of initialization, and reading any other parameters from PARM, SYSIN, or the system console, the parameter manager domain is responsible for the management of the SIT.

With the exception of the application domain (AP) which uses the SIT directly, the parameter manager domain passes system initialization parameters to the other CICS domains on request.

The domain initialization process is as follows:

Query the type of startup

With the exception of the trace domain, each domain asks the parameter manager for the type of startup—initial, cold, or warm. (For this purpose, the parameter manager domain treats an emergency restart as a warm start.)

Startup is initial or cold

If startup is initial or cold, domains do not read their domain records from the catalogs. Instead, they request system initialization parameters from the parameter manager domain. Because it is a cold start, the parameter manager domain returns all system initialization parameters from the SIT, modified by any overrides.

Startup is warm

If startup is warm, domains try to perform a warm start by reading their domain records from the catalogs:

• If they succeed in reading their status records, domains perform a warm start. Where applicable, they also request system initialization parameters from the parameter manager domain. Because it is a warm start, the parameter manager domain returns only those system initialization parameters supplied as overrides by PARM, SYSIN, or the system console.
• If they fail for any reason to read their status records, domains perform a cold start. They do this either by requesting all system initialization parameters from the parameter manager domain, or by using system default values if the domain does not have any system initialization parameters.

NEWSIT or new suffix

Although a START=AUTO may resolve to a warm start, parameter manager enforces most system initialization parameters if:

• You specify NEWSIT=YES as a system initialization parameter in PARM, SYSIN, or through the console.
• You specify a different SIT suffix from the previous run of CICS. Parameter manager saves the suffix from each run in the global catalog, and, if it detects a new suffix, it forces the NEWSIT=YES option.

For details of the parameters that are ignored when you specify NEWSIT=YES, see the NEWSIT parameter description in NEWSIT system initialization parameter.