Brocade Fabric OS Administrators Guide (Supporting Fabric OS v7.3.0) - Manual (Page 66)

• 0f is the domain ID.
• 1e is the area ID.
• 00 is the assigned AL_PA.
From this information, you can determine which switch the device resides on from the domain ID,
which port the device is attached to from the area ID, and if this device is part of a loop from the
AL_PA number.
Fixed addressing mode
With fixed addressing mode, each port has a fixed address assigned by the system based on the port
number.
This address does not change unless you choose to swap the address using the portSwap command.
Fixed addressing mode is the default addressing mode used in all platforms that do not have Virtual
Fabrics enabled. When Virtual Fabrics is enabled on the Brocade Backbone, fixed addressing mode is
used only on the default logical switch.
10-bit addressing (mode 0)
The 10-bit addressing mode is the default mode for all the logical switches. This addressing scheme is
flexible to support a large number of F_Ports. In the regular 10-bit addressing mode, the portAddress
--auto command supports addresses from 0x00 to 0x8F.
NOTE
The default switch in the Brocade Backbones uses the fixed addressing mode.
The 10-bit addressing mode utilizes the 8-bit area ID and the borrowed upper two bits from the AL_PA
portion of the PID. Areas 0x00 through 0x8F use only 8 bits for the port address and support up to 256
NPIV devices. A logical switch can support up to 144 ports that can each support 256 devices. Areas
0x90 through 0xFF use an additional two bits from the AL_PA for the port address. Therefore, these
ports support only 64 NPIV devices per port.
10-bit addressing mode provides the following features:
• A PID is dynamically allocated only when the port is first moved to a logical switch and thereafter it
is persistently maintained.
• PIDs are assigned in each logical switch starting with 0xFFC0, and can go to 0x8000 in the case of
64-port blades.
• Shared area limitations are removed on 48-port and 64-port blades.
• Any port on a 48-port or 64-port blade can support up to 256 NPIV devices (in fixed addressing
mode, only 128 NPIV devices are supported in non-VF mode and 64 NPIV devices in VF mode on a
48-port blade).
• Any port on a 48-port blade can support loop devices.
• Any port on a 48-port or 64-port blade can support hard port zoning.
• Port index is not guaranteed to be equal to the port area ID.
256-area addressing (mode 1 and mode 2)
The 256-area addressing mode is available only in a logical switch on the Brocade Backbone. In this
mode, only 256 ports are supported and each port receives a unique 8-bit area address. This mode
can be used in FICON environments, which have strict requirements for 8-bit area FC addresses.
Fixed addressing mode
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