Hardware Configuration Definition (HCD) provides an interactive interface that allows you to define the hardware configuration for both a processor's channel subsystem and the operating system running on the processor.
The configuration you define with HCD may consist of multiple processors with multiple channel subsystems, each containing multiple partitions. HCD stores the entire configuration data in a central repository, the input/output definition file (IODF).
The IODF as single source for all hardware and software definitions for a multi-processor system eliminates the need to maintain several independent MVSCP or IOCP data sets. That means that you enter the information only once using an interactive dialog.
The z/OS and z/VM Hardware Configuration Manager (HCM) is a PC based client/server interface to HCD that combines the logical and physical aspects of hardware configuration management. In addition to the logical connections, you can also manage the physical aspects of a configuration. For example, you can effectively manage the flexibility offered by the FICON infrastructure (cabinet, cabling).
All updates to your configuration are done via HCM’s intuitive graphical user interface and, most important, due to the client/server relationship with HCD, all changes of the logical I/O configuration are written into the IODF and fully validated and checked for accuracy and completeness by HCD, thus avoiding unplanned system outages due to incorrect definitions.
For z/OS only, HCM also allows you to display operational data such as system status information and operate on the switch via an interface to the I/O Operations function of System Automation on the host.