H3C Technologies H3C S5830V2 Series Switches - Manual (Page 127)

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Configuring FIP snooping
Overview
A node must register with an FC fabric to communicate with devices in the FC SAN. An FC switch has
point-to-point connections with nodes and brings up an interface connected to a node only after the
node completes fabric login on the interface.
In an FCoE implementation, Transit switches can be present between ENodes and FCF switches, so the
connections between ENodes and FCF switches are no longer point-to-point. In this case, a node that has
not performed fabric login might communicate with the FC SAN. For example, two ENodes are
connected to one FCF switch through a Transit switch. After one ENode has registered with the FCF
switch and the corresponding interface is brought up, the other ENode can also communicate with the
FC SAN.
FCoE Initialization Protocol Snooping (FIP snooping) is a security feature that can run only on Transit
switches in an FCoE network. By checking source MAC addresses of FCoE frames, FIP snooping enables
a Transit switch to forward FCoE frames only between the ENode that has performed fabric login and the
FCF switch that has accepted its fabric login.
FIP snooping network diagram
Figure 36 shows a typical FIP snooping network diagram.
Figure 36 FIP snooping network diagram
Ethernet interfaces on a Transit switch can operate in ENode or FCF mode. An Ethernet interface
connected to an ENode must be configured to operate in ENode mode, and an Ethernet interface
connected to an FCF switch must be configured to operate in FCF mode.
To control packet exchange between ENodes and FCF switches, enable FIP snooping and configure the
Ethernet interfaces to operate in a correct mode on the Transit switch.
How FIP snooping works
After FIP snooping is enabled for a VLAN, Ethernet interfaces on the Transit switch establish FIP snooping
rules according to FIP frames (with EtherType as 0x8914) and then control the forwarding of FCoE frames
(with EtherType as 0x8906) based on the FIP snooping rules.
FCF
mode ENode
mode
ENode
mode
FCF switch
Transit switch
Fabric
ENode
FCF switch
FCF
mode