Brocade Network OS Administrator’s Guide v4.1.1 - Manual (Page 339)

and the network happens to the router’s MAC address at Layer 2. This means VN1 is always
communicating with VF1 at Layer 2.
2. In a Brocade VCS Fabric implementation, all FC services are available on every cluster unit. This
means there is Fibre Channel Network Switch (FCNS) available on both FCF1 and FCF2. The FCNS
service functions identically as it does in an FC SAN. As a result, VN1 discovers VN2.
3. VN1 attempts an N_Port Login (PLOGI) to VN2, with the frame information shown at point 1 in the
following figure. The Layer 2 header contains VF1 as the destination MAC address. The Layer 3
header (in this case, the FC header) contains the actual DID and SID of the initiator and the target
respectively.
In this example, because VN1 is connected to the FCF with a Domain ID of 1, its PID is 010100.
Similarly, because VN2 is connected to FCF3, its FC address is 030100.
FIGURE 41 FCoE end-to-end header process
4. When FCF-A receives the frame on VF1, it performs a Layer 3 lookup. It looks up the DID in the FC
header and determines that the frame is destined to a non-local domain. FCF-A decodes the next
hop needed to reach the destination domain of 3, based on Fabric Shortest Path First (FSPF). It is at
this point that it does something different than a normal IP router.
5. FCF-A now knows that it needs to reach FCF-C. Each FCF in the Brocade VCS Fabric is assigned
an FCF MAC address. FCF-A constructs the Layer 2 header based on this information. So, the
Configuring FCoE interfaces
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