Chapter 21: Configure the Mainframe

This chapter provides an overview of the areas which need to be changed on your mainframe to support Remote IMS. It is not a complete description of the issues which may arise for your installation. You need to refer to your mainframe product manuals for a complete description of the installation and configuration process. The following IBM manuals are a good starting point:

GC28-1807 MVS Planning APPC/MVS Management
SC26-3060 IMS/ESA V4 DC Administration Guide
SC26-8014 IMS/ESA V5 Administration Guide:TM
SC26-8731 IMS/ESA V6 Administration Guide:TM

21.1 APPC/MVS

You need to define the APPC/MVS TP Profile for the Remote IMS Server. The Transaction Program Name (TPN) must match the TP-Name defined in the PC's CPI-C Side File or the TPNAME= parameter in Mainframe Manager Server configuration. For example:

TPADD TPSCHED_EXIT(DFSTPPE0) 
           TPNAME(MFDBTPN)
           SYSTEM

           ACTIVE(YES)
           TPSCHED_DELIMITER(##)
              TRANCODE=MFDBSRVR

              CLASS=15
              MAXRGN=20
              RACF=NONE
              ##

The CLASS value must be a valid dependent region class for IMS/ESA.

The MAXRGN value indicates the number of regions, servicing the CLASS, into which this transaction can be scheduled. You should set this value large enough for the number of concurrent Remote IMS users you want. In general, you should not set this value larger than the number of available dependent regions you have running for this CLASS. However, this general rule does not apply if you are dynamically starting or stopping dependent regions based on Remote IMS (or other) usage.

The TRANCODE-name becomes the IMS/ESA Trancode-name and must match the load module-name for the Remote IMS Server.

The RACF setting should be chosen to meet your company's requirements.

You must also define an APPC/MVS LU for IMS/ESA APPC. For example:

LUADD
          ACBNAME(IMSLU62)
          SCHED(IMSID)
          BASE

          TPDATA(SYS1.APPCTP)
          TPLEVEL(SYSTEM)

The ACBNAME must match the Partner-LU defined in the PC's CPI-C Side File or the LUNAME= parameter in Mainframe Manager Server configuration.

The IMSID is the name of your IMS/ESA system and is used by APPC/MVS to match your IMS system with the LU. Refer to your IMS/ESA installation for this name.

21.2 VTAM

A VTAM APPL must be defined which is used by APPC/MVS to manage the LU for IMS/ESA APPC applications. This APPL-name must be different than the one used by IMS/ESA for non-LU 6.2 devices. This APPL-name must match the ACBNAME in the APPC/MVS LU definition and either the LU-name in the Partner-LU defined in the PC's CPI-C Side File or the LUNAME= parameter in Mainframe Manager Server configuration. For example:

IMSLU62 APPL ACBNAME=IMSLU62 
                  APPC=Y
                  .....

21.3 IMS/ESA

There are no Trancode definitions required in IMS/ESA for CPI-C driven transactions. The Trancode definition is created dynamically by IMS/ESA for these types of transactions. The Trancode-name in IMS/ESA is the TRANCODE-name defined in the APPC/MVS TP Profile. The Trancode-name must match the name of the load module you created for the Remote IMS Server program. Once the Trancode is dynamically created by IMS, you can display it the same as any other Trancode, for example, using /DIS TRAN MFDBSRVR.

IMS/ESA must be started with APPC active (APPC=Y) or you can start APPC dynamically after IMS/ESA is started using operator commands.

You must have dependent regions available which can service the CLASS indicated for this Trancode in your APPC/MVS definitions. You should consider setting up dedicated dependent regions and a unique class for this transaction, or CPI-C driven transactions in general, as the regions may be occupied for long periods of time, especially during unit testing.