The symptoms are as follows:
When an initiator is added to the storage device, the WWN of the server cannot be detected.
Step 1 Log in to the ISM and select the storage device node in the navigation tree.
Step 2 Choose Device Information > Port. In the function pane, select the Fiber Channel host port that is connected to the application server.
Step 3 Right-click the Fiber Channel host port and choose Modify from the shortcut menu.
Step 4 In the Modify FC Port Information dialog box that is displayed, set the configuration mode to Loop. Then, proceed as prompted.
Step 5 On the application server, set the HBA mode to point to point .
Step 6 On the ISM, re-detect the WWN of the application server.
otherwise a switch can be used in between with Fabric or Loop Mode
When Connecting the Server and SAN Storage FC port directly back to back in fabric or Loop Mode the port is not up
Therefore, we have the following conclusion:
The WWN of the application server at the storage device side cannot be detected if the port mode is set to Fabric or Loop with back to back connection