HP A7533A HP StorageWorks Fabric OS 6.1.1 administrator guide (5697-0235, Dece - Page 254

To represent all iSCSI initiators and sessions, each iSCSI portal has one iSCSI virtual initiator (VI) to the FC fabric that appears as an N_Port device with a special WWN format. Regardless of the number of iSCSI initiators or iSCSI sessions sharing the portal, Fabric OS uses one iSCSI VI per iSCSI portal. Figure 19 shows the interaction of different layers from the iSCSI initiator stack to the FC target stack, including the iSCSI gateway service used during protocol translation. A pplic a tion SCSI iS C S I T C P /IP iS C S I initiator iS C S I T C P /IP iS C S I virtual target (V T ) FC P (FC -4) F C (F C -2/F C -3) iS C S I virtual initiator (V I) S torage (device s erver) SCSI FCP FC F C target iS C S I gateway s ervic e 40. 3 Figure 19 iSCSI-to-FC translation Basic versus advanced LUN mapping Fabric OS provides the following two methods to map physical FC targets (LUNs) to iSCSI virtual targets (VTs): • "Basic LUN mapping" on page 254 • "Advanced LUN mapping" on page 255 Basic LUN mapping Fabric OS provides a mechanism that maps LUNs to iSCSI VTs, a one-to-one mapping with unique iSCSI Qualified Names (IQNs) for each target. It presents an iSCSI VT for each native FC target to the IP network and an iSCSI VI for each iSCSI port to the FC fabric. Figure 20 shows a basic LUN mapping scenario for an FC target with four LUNs. iS C S I virtual target (V T ) F C target LUN LUN 0 0 1 1 2 2 3 3 40. 9 Figure 20 iSCSI VT basic LUN mapping 254 iSCSI Gateway services