HP StorageWorks 8/80 HP StorageWorks Fabric OS 6.1.x administrator guide (5697 - Page 298

If an FR4-18i blade is attached to an edge fabric using an EX_Port, it will create translate phantom domains in the fabric corresponding to the imported edge fabrics with active LSANs defined. If you import devices into the backbone fabric, then a translate phantom domain is created in the backbone device in addition to the one in the edge fabric. If you lose connectivity to the edge fabric due to link failures or disabling the IFL, by issuing the portDisable command from the switch in the attached fabric, translate phantom domains remain visible. This prevents unnecessary fabric disruptions caused by translate phantom domains repeatedly going offline and online due to corresponding IFL failures. To remove the translate phantom domain from the backbone, disable all EX_Ports or VEX_Ports through which the translate phantom domain was created. Figure 33 shows another metaSAN consisting of a host in Edge SAN 1 connected to storage in Edge SAN 2 through a backbone fabric connecting two 4/256 SAN Director, each containing an FR4-18i. 4/256 SAN Director ISL with FR4-18i blade 4/256 SAN Director with FR4-18i blade EX_Port EX_Port E_Port Backbone fabric IFL IFL Edge SAN 1 Edge SAN 2 E_Port = LSAN Figure 33 Edge SANs connected through a backbone fabric Proxy devices A 400 MP Router, 4/256 SAN Director or DC Director with an FR4-18i achieves interfabric device connectivity by creating proxy devices (hosts and targets) in attached fabrics that represent real devices in other fabrics. For example, a host in Fabric 1 can communicate with a target in Fabric 2 as follows: • A proxy target in Fabric 1 represents the real target in Fabric 2. • Likewise, a proxy host in Fabric 2 represents the real host in Fabric 1. The host discovers and sends Fibre Channel frames to the proxy target. The 400 MP Router, 4/256 SAN Director or DC Director with an FR4-18i receives these frames, translates them appropriately, then delivers them to the destination fabric for delivery to the target. The target responds by sending frames to the proxy host. Hosts and targets are exported from the edge SAN to which they are attached and, correspondingly, imported into the edge SAN reached through Fibre Channel routing. Figure 34 illustrates this concept. 298 Using the FC-FC Routing Service