R21xx-HP FlexFabric 11900 FCoE Configuration Guide

Procedure for receiving and sending FC frames over Ethernet

An FC frame is transmitted over Ethernet using the following workflow:

• FIP establishes a virtual link between the VFC interface of the FCF switch and the VN interface of the

ENode or between VFC interfaces of two FCF switches.

• After the virtual link is established, the FCF switch encapsulates the FC frame in an FCoE frame and

sends it out.

• After receiving the FCoE frame, the FCF switch removes its Ethernet header to send the original FC

frame to the upper layer for processing.

How FIP works

FIP sets up and maintains virtual links between a VFC interface and a VN interface or between VFC

interfaces.

Two categories of packets are used in FIP: Discovery Solicitation and Discovery Advertisement. There are

two types of Discovery Advertisement:

• Solicited Discovery Advertisement—A reply for a Discovery Solicitation.

• Unsolicited Discovery Advertisement—Periodically sent.

The following example shows how a virtual link is set up between an FCF switch and an ENode.

Figure 9 FIP operation

As shown in Figure 9, the following workflow is used to set up a virtual link:

1. The ENode sends a Discovery Solicitation containing its FCoE MAC address.

2. After receiving the Discovery Solicitation, the FCF switch acts differently depending on whether the

receiving VFC interface is bound to the FCoE MAC address:

{ If it is not bound, the switch learns the FCoE MAC address and replies with a solicited

Discovery Advertisement, whose fcf priority field carries the FCF priority of the VFC interface.

{ If it is bound, the switch checks whether the FCoE MAC address matches the bound FCoE MAC

address. If they match, it replies with a solicited Discovery Advertisement, whose fcf priority

(1) Send Discovery Solicitation

Learn FCoE MAC address

FCF

ENode

(2) Send solicited Discovery

(3) Send solicited Discovery

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(4) Send FLOGI request

Check FCoE MAC address

(5) Send FLOGI LS_ACC

(6) Send solicited Discovery

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