IMS High Availability Large Database (HALDB) Toolkit

The IMS HALDB Toolkit's architecture is centered around a batch processing model, designed to operate within the z/OS environment. The main components include the Partition Management Utility, the Index Healing Utility, and the Database Merge Utility. These utilities are accessed through JCL and ISPF panels, providing a user-friendly interface for database administrators.

The Partition Management Utility allows for the consolidation or splitting of HALDB partitions. This utility processes the HALDB structure, updates DBRC, and manages the physical data sets. The Index Healing Utility is used to rebuild secondary indexes after database reorganizations.

It reads the database data, reconstructs the index entries, and updates the index data sets. The Database Merge Utility combines multiple HALDBs into a single database. It merges the data sets, updates DBRC, and ensures data consistency.

Communication between components is primarily through the z/OS operating system and IMS control blocks. The toolkit utilizes DBRC for database metadata and control information, ensuring data integrity and consistency. The toolkit does not expose any APIs.

The toolkit integrates with the z/OS security infrastructure, using RACF or equivalent for authentication and access control. All operations are logged, providing a detailed audit trail of database changes and administrative actions. The toolkit's design emphasizes efficiency and reliability, ensuring that database operations are performed with minimal downtime and risk.

The toolkit's architecture is optimized for batch processing, making it suitable for large-scale database environments.