Start options

When you start a queue manager, a special routine called the system parameter module is invoked. We can specify the name of a system parameter module if you use the PARM keyword. A system parameter module provides information specified when the queue manager was customized. In Figure 82, the user message CSQY001I indicates the name of the system parameter module that was used, in this case, CSQ1ZPRM. For more information about this, see the WebSphere MQ for z/OS System Setup Guide.

We can also use the ENVPARM option to substitute one or more parameters in the JCL procedure for the queue manager.

For example, we can update your queue manager startup procedure, so that the DDname CSQINP2 is a variable. This means that we can change the CSQINP2 DDname without changing the startup procedure. This is very useful for implementing changes, providing backouts for operators, and so on.

Suppose your start-up procedure for queue manager CSQ1 looked like Figure 4.

Figure 4. Sample start-up procedure

//CSQ1MSTR PROC INP2=NORM
//MQMESA   EXEC PGM=CSQYASCP
//STEPLIB  DD   DISP=SHR,DSN=thlqual.SCSQANLE
//         DD   DISP=SHR,DSN=thlqual.SCSQAUTH
//         DD   DISP=SHR,DSN=db2qual.SDSNLOAD
//BSDS1    DD   DISP=SHR,DSN=myqual.BSDS01
//BSDS2    DD   DISP=SHR,DSN=myqual.BSDS02
//CSQP0000 DD   DISP=SHR,DSN=myqual.PSID00
//CSQP0001 DD   DISP=SHR,DSN=myqual.PSID01
//CSQP0002 DD   DISP=SHR,DSN=myqual.PSID02
//CSQP0003 DD   DISP=SHR,DSN=myqual.PSID03
//CSQINP1  DD   DISP=SHR,DSN=myqual.CSQINP(CSQ1INP1)
//CSQINP2  DD   DISP=SHR,DSN=myqual.CSQINP(CSQ1&INP2.)
//CSQOUT1  DD   SYSOUT=*
//CSQOUT2  DD   SYSOUT=*

If you then start the your queue manager with the command:

    +CSQ1 START QMGR

the CSQINP2 actually used is a member called CSQ1NORM.

However, suppose you are putting a new suite of programs into production so that the next time you start queue manager CSQ1, the CSQINP2 definitions are to be taken from member CSQ1NEW. To do this, you would start the queue manager with this command:

    +CSQ1 START QMGR ENVPARM('INP2=NEW')

and CSQ1NEW would be used instead of CSQ1NORM. Note that z/OS limits the

KEYWORD=value specifications for symbolic parameters (as in INP2=NEW) to 255 characters.