Disabling the vSAN iSCSI Target Service stops the service that presents iSCSI targets and LUNs to initiators, but it does not automatically delete the targets or LUNs. The vSAN administration guidance states that if an administrator wants to remove vSAN iSCSI objects and reclaim capacity, the LUNs and targets must be deleted manually before or after disabling the service. Therefore, when the service is disabled, the existing targets and LUNs remain in the vSAN datastore but are no longer accessible to the clustered legacy application. This behavior prevents accidental deletion of application or quorum data simply because the service is turned off. The targets are not archived for a fixed retention period, and they are not automatically migrated to another namespace for retention. They are also not deleted automatically. Operationally, administrators should confirm that the legacy application no longer depends on the LUNs before disabling the service or should remove the iSCSI objects through the supported workflow when decommissioning is complete. Reference topics: vSAN iSCSI Target Service, Disable iSCSI Target Service, LUN and Target Lifecycle, vSAN Object Retention.

Explanation:
LUN Masking = A security process performed on the storage array by which specific storage components are hidden to prevent unauthorized access to data; Datastore Cluster = A collection of shared resources with a shared management interface that enables resource allocation policies; SAN Fabric = A dedicated high-performance network infrastructure for storage devices; Datastore = A manageable storage entity used as a repository for Virtual Machine files including log files, scripts, configuration files and virtual disks; Host Bus Adapter (HBA) = Added to an ESX host server to allow the host access to the dedicated storage area network; Zoning = A security process completed on the Storage Area Network to ensure only certain devices can communicate with each other.
These definitions describe the core components of a Fibre Channel SAN design in a VCF Workload Domain. LUN masking is performed on the storage array and controls which hosts can see specific LUNs, preventing unauthorized access to storage. A datastore cluster is a collection of datastores managed as a shared resource pool, allowing placement and balancing policies through Storage DRS. A SAN fabric is the dedicated high-performance network that interconnects ESX hosts, Fibre Channel switches, and storage arrays. A datastore is the vSphere logical storage container where VM configuration files, virtual disks, logs, and related files reside. A Host Bus Adapter is the physical or virtual adapter in the ESX host that connects the host to the Fibre Channel storage area network.
Zoning is performed on the Fibre Channel fabric and controls which initiators and targets can communicate. Together, zoning and LUN masking provide layered access control, while datastores and datastore clusters provide the vSphere consumption model. Reference topics: Fibre Channel SAN Concepts, SAN Fabric, Zoning, LUN Masking, VMFS Datastores, Datastore Clusters.