3.1 Map devices
After getting an IP address and entering ATTO ExpressNAV, you must map devices so that the FibreBridge can access the devices in your network.
The ATTO FibreBridge allows parallel SCSI devices to participate in a Fibre Channel arbitrated loop or on a fabric. Fibre Channel and parallel SCSI use different models to address devices. The FibreBridge translates between these addressing models.
FibreBridge mapping
On a Fibre Channel Arbitrated Loop, the FibreBridge appears at a single Arbitrated Loop Port Address (AL_PA). Each device on an arbitrated loop is assigned a unique AL_PA during loop initialization. The FibreBridge supports both modes of AL_PA assignment, commonly referred to as hard and soft addressing.
WWN: To identify each Fibre Channel device while addressing, each Fibre Channel device is assigned a unique World Wide Name (WWN). The
Field | WWN | Company ID | Device ID | |||||
Name | Format |
|
|
|
|
|
| |
|
|
|
|
|
|
|
|
|
Byte | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
|
|
|
|
|
|
|
|
|
Value | 20 | 00 | 00 | 10 | 86 | xx | xx | xx |
|
|
|
|
|
|
|
|
|
Soft addressing allows the loop initialization master to assign the FibreBridge a unique address during the loop initialization process. The address assigned cannot be determined before loop initialization. Adding new devices to an arbitrated loop may change the address assigned to the FibreBridge.
Hard addressing allows a predetermined address to be assigned to the FibreBridge. The FibreBridge tries to acquire the desired hard address. If another device has already been assigned the specified address, the FibreBridge acquires a currently unassigned address.
Note
The default mode is soft addressing.
SCSI device mapping
SCSI devices connected to the FibreBridge are viewed as Fibre Channel LUNs to the host computer. SCSI devices must be on the same addressing level as the SCSI portion of the FibreBridge. The FibreBridge SCSI ID must be set to a different SCSI ID from the other devices on the same bus.
The ATTO ExpressNAV interface graphically shows you current mapping and the SCSI devices available for mapping. Refer to Interface options on page 25.
Use the ExpressNAV interface to map devices automatically or to customize mapping. You may modify the mapping as needed to make a device inaccessible to a host or to replace a non- functioning mapped unit.
Note
It is not necessary to set all mapped devices online: SCSI commands sent to offline devices are rejected.
17
ATTO Technology Inc. FibreBridge Installation and Operation Manual
