Active IQ OneCollect is the appropriate discovery tool when the engineer needs an end-to-end inventory of a SAN environment. NetApp describes OneCollect as a structured data-collection utility that gathers information across storage systems, hosts, fabrics, and switches. That scope is specifically useful when existing documentation is missing and the engineer must understand initiators, HBAs, zoning or fabric details, host configuration, and storage targets before remediation or migration work. Upgrade Advisor is intended for ONTAP upgrade planning, while Unified Manager focuses on monitoring and management rather than broad discovery collection. Config Advisor validates configuration and cabling against supported practices, but it is not the primary end-to-end inventory collector described in this scenario. Relevant SAN ONTAP topics are SAN discovery, OneCollect data collection, host and fabric inventory, configuration assessment, and implementation documentation.