Defining resources in CICS control tables

Some CICS® resource are defined in CICS control tables.

The tables and their resource definitions are created by macros. You must use macros to define non-z/OS Communications Server networks and terminals, non-VSAM files, databases, and resources for monitoring and system recovery. You must use RDO for VSAM files, programs, map sets, partition sets, queues, transactions, and profiles.

For each of the CICS tables listed in Introduction to CICS control tables and macros, complete the following steps:
  1. Code the resource definitions you require.
  2. Assemble and link-edit these definitions, using the CICS-supplied procedure DFHAUPLE, to create a load module in the required CICS load library. The load library is either CICSTS55.SDFHLOAD or CICSTS55.SDFHAUTH, which you must specify by the NAME parameter of the DFHAUPLE procedure. The CICS-supplied macros used to create the CICS tables determine whether tables are loaded above the 16MB line. All tables, other than the TCT, are loaded above the 16MB line.
  3. Name the suffix of the load module by a system initialization parameter. For most of the CICS tables, if you do not require the table you can code tablename=NO. The exceptions to this rule are as follows:
    • CLT: specifying CLT=NO causes CICS to try and load DFHCLTNO. The CLT is used only in the alternate CICS, when you are running CICS with XRF, and is always required in that case.
    • SIT: specifying SIT=NO causes CICS to try and load DFHSITNO. The SIT is always needed, and you can specify the suffix by coding the SIT system initialization parameter.
    • TCT: specifying TCT=NO causes CICS to load a dummy TCT, DFHTCTDY.
    • TLT: terminal list tables are specified by program entries in the CSD, and do not have a system initialization parameter.
    • MCT: specifying MCT=NO causes the CICS monitoring domain to dynamically build a default monitoring control table. This ensures that default monitoring control table entries are always available for use when monitoring is on and a monitoring class (or classes) are active.
  4. If you are running CICS with XRF, the active and the alternate CICS regions share the same versions of tables. However, to provide protection against DASD failure, you could run your active and alternate CICS regions from separate sets of load libraries—in which case, you should make the separate copies after generating your control tables.

Table 1 lists all the CICS tables that can be assembled, link-edited, and installed in your CICS libraries.

Table 1. CICS tables that you can assemble, link-edit, and install in CICS libraries
Table Module Name Abbreviation Required load library
Command list table DFHCLTxx CLT SDFHAUTH
Data conversion table DFHCNV CNV SDFHLOAD
File control table DFHFCTxx FCT SDFHLOAD
Monitor control table DFHMCTxx MCT SDFHLOAD
DL/I program specification block DFHPSBxx PSB SDFHLOAD
Recoverable service element table DFHRSTxx RST SDFHAUTH
System initialization table DFHSITxx SIT SDFHAUTH
System recovery table DFHSRTxx SRT SDFHLOAD
Terminal control table DFHTCTxx TCT SDFHLOAD
Terminal list table DFHTLTxx TLT SDFHLOAD
Temporary storage table DFHTSTxx TST SDFHLOAD
Transaction list table DFHXLTxx XLT SDFHLOAD

The Program List Table (PLT) used to be a member of the above table. However, PLTs no longer need to be assembled. CICS reads the source code for PLTs and uses it to define the required PLT processing.

You can generate several versions of each CICS control table by specifying SUFFIX=xx in the macro that generates the table. This suffix is then appended to the default 6-character name of the load module.

To get you started, CICS provides the sample tables listed in Table 2 in the CICSTS55.SDFHSAMP library:

Table 2. Sample CICS system tables in the CICSTS55.SDFHSAMP library
Table Suffix Notes
Command list table (CLT) 1$ XRF regions only
Monitor control table (MCT) A$ For a CICS AOR
Monitor control table (MCT) F$ For a CICS FOR
Monitor control table (MCT) T$ For a CICS TOR
Monitor control table (MCT) 2$
System initialization table (SIT) $$ Default system initialization parameters
System initialization table (SIT) 6$
System recovery table (SRT) 1$
Terminal control table (TCT) 5$ Non-z/OS Communications Server terminals only

Although you can modify and reassemble the tables while CICS is running, you must shut down and restart CICS to make the new tables available to CICS. (The command list table (CLT) is exceptional in that a new table can be brought into use without shutting down either the active CICS region or the alternate CICS region.)