iSR6200 Intelligent Storage Router Installation Guide - QLogic

2–PlanningFibre Channel Switches Required for VPGroupsFibre ChannelThe Fibre Channel ports automatically discover all Fibre Channel target devices,whether connected directly (loop) or by fabric (switch).iSCSIThe iSCSI ports automatically present targets discovered on the Fibre Channelports. If the Fibre Channel target’s LUN 0 is a controller LUN, it becomesaccessible (mapped) to all iSCSI initiators. All data LUNs are inaccessible untilmapped. The exception is if LUN 0 is a controller LUN, it is mapped automaticallyto allow for management of the Fibre Channel target controller.When an iSCSI initiator logs on, the router records the initiator’s iSCSI name andIP address. The management interface—CLI and SANsurfer RouterManager—uses the initiator information to simplify the mapping process.Fibre Channel Switches Required for VPGroupsiSR6200 uses QLogic Host Bus Adapter technology and is compatible with allFibre Channel switches from Brocade, Cisco, McData, and QLogic. If you want touse more than one VPGroup, you must use Fibre Channel switches.Fibre Channel PerformanceDistanceThe iSR6200 router supports Fibre Channel service at transmission rates of 2, 4,or 8 Gbps with a maximum frame size of 2,148 bytes. Related performancecharacteristics include the following:• Distance• Bandwidth• LatencyConsider the physical distance between Fibre Channel devices. Choose SFPtransceivers that are compatible with the cable type and distance.Each Fibre Channel port is supported by a data buffer with a three-credit capacity;that is, three maximum-sized frames. For fibre optic cables, this enables fullbandwidth over approximately 2.5 kilometers at 2Gbps (1.2 credits/Km).Beyond these distances, however, the connection loses some efficiency becausethe transmitting port must wait for an acknowledgement before sending the nextframe.2-2 ISR651101-00 G