install required CICS and IMS adapters

define queues

set up distributed queuing

Customization is described in detail in the MQSeries for MVS/ESA System Management Guide. Only the steps which are related to migration are discussed in some more detail in the following sections.

After the installation and customization has been completed, you can use an installation verification program (IVP) supplied with the product to verify that the installation has been completed successfully. Details of the IVP and customization are given in the MQSeries for MVS/ESA System Management Guide.

9.5.1.3 CICS Considerations

The CICS execution environment is the only environment for VSE/ESA based MQSeries applications. Naturally it will, therefore, be the main migration target environment.

There is a major difference between MQSeries under VSE/ESA and under OS/390:

Under VSE/ESA MQSeries itself and MQSeries applications run under CICS. Therefore, MQSeries resources (such as programs, queues) must be defined in CICS/VSE. Access to both MQSeries and CICS resources from an application (which includes both CICS commands and MQI calls) does not require additional installation or customization effort.

Under OS/390 MQSeries runs in an address space independent of CICS. To allow CICS applications to access MQSeries resources (through API calls) the CICS adapter must be installed and customized in the respective CICS region. The CICS adapter connects a CICS subsystem to an MQSeries subsystem, enabling CICS application programs to participate in message-driven processing.

The CICS adapter provides two main facilities:

a set of control functions for use by system programmers and administrators to manage the adapter.

Control functions let you manage the connections between CICS and MQSeries dynamically. They may be invoked using the CICS adapter

panels, from the command line, or from a CICS application. You can use the adapters control function to:

-start, stop and modify a connection to a queue manager

-display the current status and statistics of a connection

-start and stop an instance of the task initiator transaction, CKTI

-display details of the current instances of CKTI

-display details of the CICS tasks currently using the adapter.

MQI support for CICS applications.

For performance, the CICS adapter can handle up to eight MQI calls concurrently. For transaction integrity, the adapter fully supports syncpointing under the control of the CICS syncpoint manager. The adapter also supports security checking of MQSeries resources when used with an appropriate security management product, such as RACF. The adapter provides high availability with automatic reconnection after

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IBM OS/390 manual Cics Considerations

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.