Also, you should remove the parameters such as REUSE, RSL, and DEVICE from the DCT specification; these parameter are obsolete.

Note: CICS TS provides a facility that allows an extrapartition data set to be used to submit jobs to MVS.

FCT Remove the CSD entry from FCT (it is now in the SIT), plus all VSAM entries (VSAM resource entries are autoinstall) from the FCT, then re-assemble the FCT and migrate the table to the CSD.

JCT ²INPUT² JOUROPT and BUFSUV parameters are obsolete. CICS Transaction Server does not support tape logging. Also, note that log format is SMF only.

MCT Additional control over what is monitored is available with CICS/ESA. Measuring CPU time is no longer an option, CICS always measures CPU time. Also, parameter CONV is replaced by SIT parameter MNCONV. If your existing MCT specifies CONV=YES, you should remove this and specify MNCONV as a system initialization parameter (or you can set the option dynamically using a CEMT SET MONITOR or EXEC CICS SET MONITOR command).

NLT is obsolete.

PCT is obsolete, you must use RDO. Be sure to migrate all PCT entries to CSD on VSE before migrating to CICS/ESA.

PLT The sequence of events during initialization is changed in CICS/ESA. In particular, there are now two phases of program list table (PLT) processing during initialization. These two phases are separated in the same way as the first and second quiesce PLT shutdown programs, by the inclusion of DFHPLT TYPE=ENTRY,PROGRAM=DFHDELIM at the appropriate point among the DFHPLT TYPE=ENTRY macros for the programs. During the first phase, you can run only the programs that enable your user exits for restart processing. Another result of the change to PLT processing during startup is in the way CICS loads the PLT. This change means that you no longer need an RDO entry for the PLT itself. However, you must continue to define to CICS the PLT programs listed in the table by suitable program entries in the CSD. Please note that the

first-phase PLTPI programs must run in AMODE 31 mode, otherwise they fail with an ABEND 0C4.

PPT is obsolete, you must use RDO. You are recommended not to migrate the definitions, but use the new autoinstall facility for programs and maps instead. Plus, you should review all resident programs on your CICS/VSE system. If the only reason a program was made resident was due to high usage, this reason is now eliminated (CICS/ESA uses an LRU algorithm for compression).

SNT DFHSNT macro is obsolete and no longer supplied. To define user attributes you must add them to the user profiles maintained by your external security manager. If you are using RACF, you define user attributes in the CICS segment of the user profiles in the RACF database.

SRT review the default CICS/ESA table for additional entries, other than the standard MVS error codes.

Chapter 6. CICS 141

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IBM OS/390 manual Cics

OS/390 specifications

IBM OS/390, a versatile operating system, was a cornerstone in enterprise environments and played a pivotal role in mainframe computing. Released in the mid-1990s, OS/390 combined the strengths of IBM's MVS (Multiple Virtual Storage) with new features and enhancements, targeting scalability, reliability, and performance in demanding business applications.

One of the key features of OS/390 was its robust support for multiple users and processes. The system allowed thousands of concurrent users to access applications and data, ensuring high availability and minimizing downtime—a critical requirement for many large organizations. This scalability was supported through various enhancements in memory management and processor scheduling, enabling optimal resource allocation across diverse workloads.

OS/390 was known for its superior workload management capabilities. The Workload Manager (WLM) component allowed administrators to define service policies, specifying how system resources would be allocated according to the priority of tasks. This ensured that critical business processes received the necessary resources while less critical tasks were managed more flexibly.

Another significant characteristic of OS/390 was its commitment to security. The operating system provided comprehensive security features, including user authentication, data encryption, and auditing capabilities. This focus on security was vital for organizations handling sensitive data, ensuring compliance with regulations and safeguarding against unauthorized access.

OS/390 also supported advanced technologies that facilitated integration and development. The system included features like the IBM CICS (Customer Information Control System) for transaction processing and IMS (Information Management System) for database management. These technologies allowed organizations to build robust, high-performance applications tailored to specific business needs.

The ease of network integration was another strength of OS/390. With the advent of the Internet and global connectivity, OS/390 systems could easily interface with various network protocols, enabling businesses to operate in a connected world. This inclusion paved the way for many organizations to expand their capabilities and offer new services, driving digital transformation.

In conclusion, IBM OS/390 represented a significant advancement in mainframe technology, combining scalability, security, and robust workload management. Its rich feature set and support for critical enterprise applications solidified its role as a vital component of many organizations' IT infrastructures, ensuring they could meet their operational challenges head-on while supporting future growth. As technology continues to evolve, the legacy of OS/390 remains influential in the realm of computing.