Exam NS0-185 Topic 1 Question 103 Discussion

This question checks how ONTAP exposes LUN paths across nodes after cluster expansion. ONTAP SAN pathing is governed bySelective LUN Map (SLM)behavior. ONTAP documentation states that SLM reduces host-to-LUN paths by making a LUN accessible only through paths on the node owning the LUN and its HA partner (unless configured otherwise). That means that after you add nodes, hosts will not automatically gain paths through the new nodes for existing LUNs unless you intentionally adjust LUN reporting.
ONTAP provides the lun mapping add-reporting-nodes command for exactly this purpose: it is used before or after data mobility events that modify the owning node of the LUN, to add optimized nodes (and therefore paths) to the LUN mapping's reporting-nodes list. In other words, if the administrator wants existing LUNs to
"use paths on the new nodes," the ONTAP-side requirement is to add those nodes (and their partners, as applicable) as reporting nodes for the relevant LUN mappings or volumes/aggregates that host those LUNs.
Options A and D (port/host rescans) arehost-side discovery actions. They can only discover paths that ONTAP is already presenting. Without adding reporting nodes, ONTAP may not advertise those LUNs through the new nodes, so host rescans alone do not satisfy the requirement. Option C ("lun bind create") is not the appropriate ONTAP mechanism for enabling additional node paths for existing LUNs and is not the documented workflow for SLM path expansion.
Therefore, the required step isB. Use the lun mapping add-reporting-nodes command.