Configuration creation - building and maintaining a configuration description that is resource-specific.

Updating configuration information - providing vital product data, topology data, and other configuration data when a change is made to the configuration.

Accessing configuration information - providing information on the actual or planned resources, specific resource attributes, paths to or from a target resource, version information for software, and similar data.

30.7.3Methodology

Configuring the OS/390 hardware, logical connection, and subsystem environment is straightforward and documented in this book. For example, products such as HCD and System Automation for OS/390 (which includes the functions of ESCON manager) can be used to define the hardware configuration and access paths. The critical element is ensuring that related definitions for hardware and software components are kept together somewhere. For example, a DASD volume has a UCB address, I/O device address, and volume name. It is located in a particular hardware device. It is accessible through one or more control units (and associated ESCON ports). It may be dedicated to a particular workload or business organization. It is part of a pool used by a particular storage class. Managing the configuration means pulling this information together so that these relationships are known and understood, and so that systems management activities can be carried out properly using this information. The scope of a problem or change involving that DASD volume is much better known when one can see all the ²pieces² of the system where the volume is defined in some fashion. This applies to all components in the environment.

Centralizing configuration information is best done using a set of files, which may contain both text tables and diagrams. Maintaining this information across these files is important so that the other disciplines have access to accurate information. In fact, if the ²attributes² of a component - the different ways it can be identified or connected within the system - are documented, part of the change management process can verify that all of the attributes are properly accounted for in any changes that affect that component.

TME 10 Information Management provides support for combining configuration definitions for components within its repository; it can be customized to support any attributes for a component that the installation desires. This allows not only direct access to configuration information, but indirect access through change and problem activities; for example, if a problem occurs with a component, TME 10 Information Management can automatically look up the component¢ s configuration record and show what other aspects of the system may be impacted by the problem.

As the environment grows to multiple MVS images it becomes even more important to identify and maintain multiple configurations consistently. Where possible system definitions should be consistent; when they cannot be, a consistent naming convention should be used.

470VSE to OS/390 Migration Workbook

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IBM OS/390 manual Methodology

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.