to 3, the FibreBridge will be at
If Address Translation is off, the FibreBridge LUN is set from jumpers on the circuit board. The factory default jumper value is LUN 14.
Fibre Channel Connect Mode (default = Arbitrated Loop (FL_Port))
Sets the FibreBridge to either Arbitrated Loop (FL_Port) mode or Point to Point (F_Port) mode. F_Port mode can only be used when connecting directly to a F_Port on a host adapter or a switch. FL_Port mode must be used when the FibreBridge is connected to a hub or there are other devices daisy chained off of the second GBIC port of the FibreBridge. F_Port mode will result in slight performance improvements. The initiator must be set to the same mode as the FibreBridge for proper operation.
Fibre Channel Frame Length (default = 2048)
Modifies the maximum number of payload data bytes in a Fibre Channel frame. Select 512 bytes, 1024 bytes or 2048 bytes. Experimenting with this value may increase performance depending on both the application and connected devices.
Open Full Duplex (default = Enabled)
Used to enable or disable Full Duplex transfer, a mode in which a Fibre Channel port can receive and transmit data at the same time, resulting in improved performance under certain conditions. The initiator must also be set for Full Duplex transfers.
Physical Device Addressing Method (default = LLLL TTTB)
If the Address Translation field is set to enabled, modifies the SCSI Address translation pattern for the FibreBridge. The number of B, T and L bits defined in the pattern will determine the number of FibreBridge busses, targets, and LUNs addressed. The position of the B, T and L bits will determine how they are mapped into the Fibre Channel LUN. A binary translation is used to convert the eight BTL bits into 256 possible unique Fibre Channel LUNs.
Using the default pattern of LLLL TTTB will allow two FibreBridge busses to be addressed. One B bit can have a value of 0 or 1. With three T bits, there is a possibility for eight unique targets on each bus. Four LUN bits allow sixteen LUNs on each target, on each bus. The decimal value of this BTL byte is what is used to determine the Fibre Channel LUN value of your connected SCSI device.
For example, if the addressing pattern is set to LLLL TTTB and a SCSI drive is set at Target ID 4 LUN 0 connected to FibreBridge bus 1. The B bit is set to binary 1, the T bits are set to binary 4 (100), the L bits are set to binary 0 (0000). The LLLL TTTB pattern will be filled in as 0000 1001 which translates to Fibre Channel LUN 9.
To modify the BTL pattern, click on the bar that contains the BTL bits. An edit window will pop up.
Use the tool to select the position and number of bits for the Bus, Target, and LUN bits. BridgeTools will indicate if an inappropriate bit pattern is selected. Each BTL designator can have any number of defined bits. Do not leave undefined bits unless they are at the most significant positions. For example, if only 5 bits need to be defined they must be in positions 0 through 4. Leaving bit 0 undefined and then assigning bits 1 through 5 is not allowed. Any one bit position cannot be assigned to more than one BTL designator. When more than one bit is required for any of the B, T or L designators, they must be next to each other. Three T bits must be assigned in consecutive positions.
A translation tool will help determine the Fibre Channel LUN for a device. Click on the View FC LUNs tab. Find the SCSI Target ID the device is set at down the
The table calculates the Fibre LUN based upon the current BTL pattern set within the Editor tab, with a separate table for devices connected to FibreBridge bus 1 and bus 2. The grayed out LUNs are “unreachable” because this is the SCSI ID the bridge SCSI port is set to. The Fibre Channel LUN in red is the ID the FibreBridge itself will assume.
Refer to the Fibre Channel to SCSI Addressing chapter in the FibreBridge manual or contact ATTO Technical Support for further assistance.
Unprocessed SCSI Command Returns (default = Queue Full)
Used to select the SCSI status command returned by the FibreBridge when it is unable to accept a new command from a host because of a temporary lack of internal resources, a rare condition. This option is available because some UNIX operating systems do not use the Queue Full command and the FibreBridge will need to send a Busy instead. Using Busy instead of Queue Full slows data transfer rates.
17 ATTO Technology BridgeTools Installation and Operation Manual