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ATTO Technology Inc. FibreBridge Installation and Operation Manual
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 64-bit WWN has the following format:
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.
Field
Name
WWN
Format
Company ID
Device ID
Byte
0
1
2
3
4
5
6
7
Value
20
00
00
10
86
xx
xx
xx
