Which statement correctly describes LUN access in SAN environments?

Which statement correctly describes LUN access in SAN environments?

• A. LUNs are accessed using block-level protocols such as iSCSI or FCP.
• B. LUNs are accessed as files over NFS.
• C. LUNs are accessed as objects via HTTP.
• D. LUNs are not accessible over SAN

Answer: (A)

In SAN environments, LUNs are presented as block storage to the host. A LUN is a logical unit of storage that the server sees as a raw block device (like a disk), onto which you can create partitions and filesystems. Access to these LUNs happens through block-level protocols such as Fibre Channel (FCP) or iSCSI, which carry SCSI commands over the network to the storage array. This is why LUNs are described as block storage in SANs. Accessing a LUN as a file over NFS isn’t correct because NFS serves files, not raw block devices; you would first put a filesystem on the LUN and then export that filesystem via NFS. Accessing LUNs as objects via HTTP is also not how SANs present storage—object protocols are for object storage, not block devices. And stating that LUNs are not accessible over SAN contradicts the fundamental purpose of a SAN, which is to provide LUNs to hosts.

In SAN environments, LUNs are presented as block storage to the host. A LUN is a logical unit of storage that the server sees as a raw block device (like a disk), onto which you can create partitions and filesystems. Access to these LUNs happens through block-level protocols such as Fibre Channel (FCP) or iSCSI, which carry SCSI commands over the network to the storage array. This is why LUNs are described as block storage in SANs.

Accessing a LUN as a file over NFS isn’t correct because NFS serves files, not raw block devices; you would first put a filesystem on the LUN and then export that filesystem via NFS. Accessing LUNs as objects via HTTP is also not how SANs present storage—object protocols are for object storage, not block devices. And stating that LUNs are not accessible over SAN contradicts the fundamental purpose of a SAN, which is to provide LUNs to hosts.