You created new LUNs for Windows Server cluster; servers can't detect.

• A. The LUNs were not formatted with the correct file system
• B. The LUNs were created but not mapped to an initiator group (igroup)
• C. The cluster nodes do not have multipathing enabled
• D. The LUNs are set to offline status by default

Answer: (B)

The essential idea is that storage must be presented to the hosts, not just created on the NetApp side. LUNs exist on a volume, but they only become visible to Windows servers when they are mapped to an initiator group (igroup) that contains the host’s initiators (the FC WWPNs or iSCSI IQNs). If the LUNs are created but not included in an igroup, there’s no path from the Windows cluster to those LUNs, so the servers won’t detect them at all.

The fix is to add the Windows cluster initiators to an igroup and map the LUNs to that igroup, then rescan disks on the Windows side (and enable multipath if you’re using it). This exposure step is what makes the LUNs appear as usable disks in the OS.