Which mechanism allows you to make LUNs available to some initiators and unavailable to others?

• A. LUN hiding
• B. LUN cloning
• C. LUN masking
• D. LUN grouping

Answer: (C)

Controlling which hosts can see and access a LUN is done with LUN masking. In ONTAP 7-mode you define initiator groups (igroups) that specify which initiators are allowed. You associate the LUN with a particular igroup, so hosts inside that group can see and access the LUN, while hosts outside the group cannot see it at all. This selective visibility is what enables you to present LUNs only to the intended initiators and keep them invisible to others, which is essential in multi-host environments to prevent unauthorized access and misprovisioning.

Other options don’t fit as well because cloning creates a duplicate of the data, not access control; grouping is about organizing LUNs for management, not restricting access; while hiding is a related concept, the standard mechanism used to control visibility and access in this context is LUN masking through igroups.