Installs, configures, upgrades, maintains, and troubleshoots IBM DB2 for z/OS subsystems. Manages ZPARMs, buffer pools, logs, BSDS, catalogs, performance, capacity, Data Sharing environments, Sysplex, Coupling Facility integration, high availability, and disaster recovery. Resolves subsystem failures, dumps, abends, and connectivity issues while supporting JCL, CICS, IMS, MQ, and distributed systems. The role also contributes to modernization, client collaboration, operational documentation, and large-scale DB2 upgrades or migrations.