A new LUN from an existing storage array is presented to a vSphere cluster. A vSphere
administrator determines that the LUN is visible on all but one ESXi host in the cluster. The
affected host is able to see existing LUNs presented from the same storage array.
What is the most likely cause?
A.
LUN Masking is improperly configured on the storage array.
B.
The SAN fabric is improperly zoned.
C.
The ESXi host has NOT been rebooted.
D.
The HBA in the host is incompatible with ESXi.
Explanation:
A is correct
LUN masking, which is commonly used for permission management. LUN masking is a process that makes a LUN available to some hosts and unavailable to other hosts.
http://pubs.vmware.com/vsphere-55/index.jsp?topic=%2Fcom.vmware.vsphere.storage.doc%2FGUID-39A4551F-4B03-43A6-BEDF-FAB1528C070D.html&resultof=%22Lun%22%20%22lun%22%20%22masking%22%20%22mask%22
-“…that the LUN is visible…” rules out Answer D.
-“…all but one ESXi host in the cluster…” rules out B.
-“The affected host is able to see existing LUNs presented from the SAME storage array.” rules out C.
So A. is the only option 😉