SAN addressing

To access a device within a Fibre Channel SAN the following addressing parameters are required (see Figure 1):

• The device number of the FCP device (the device-bus ID without the leading "0.0"). This is a two-byte hexadecimal number specifying the FCP device, and, indirectly, the port at the local FCP channel. This is the only addressing parameter configured within the IODF. The device-bus ID is the way out of the mainframe.
• The worldwide port name (WWPN) of your target port. There can be several hundred storage devices with several ports each within your storage area network. You must specify the storage device and the entry port into this storage device. For this reason, each port has a unique number, called the worldwide port name. This WWPN is eight bytes in length and is, as the name says, unique worldwide.
• The logical unit (LUN). This parameter specifies the device within the storage controller. There could be several hundred disks in your storage controller.