FCoE Cookbook for HP Virtual Connect Version 4.20 Firmware Enhancements May 2014

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FCoE Frames Analysis
For network troubleshooting, capturing frames with a protocol analyzer can be very instructive but it is necessary to
understand the way FCoE works.
FCoE traffic use a different MAC address than the MAC address of the FCoE Adapter, the physical MAC address of the
FCoE adapter (i.e. the MAC displayed in the Virtual Connect interface) is only used during FIP negotiation (FCoE
Initialization Protocol).
Figure 51: MAC address of the FCoE adapter found in the Server profile interface.
During the FIP negotiation, the FCF assigned a Fabric Provided MAC address (FPMA) to the server. This address is used for
FCoE forwarding and is the one Wireshark will detect during FCoE network captures.
The FPMA is built by appending the FCID (assigned by the Fabric to the server) to the Nexus FC-MAP.
Figure 52: The way the FPMA is built.
FC-MAPs
0E-FC-00 to 0E-FC-FF
FC-ID
E5.01.00
FC-MAP
0E-FC-00
FC_ID
E5.01.00
24 Bits
24 Bits
FPMA
48 bits
0E-FC-00-E5-01-00