Information About Fibre Channel Interfaces
The following commands will enable the default QoS configuration which must be configured for native FC
or FCoE or FC and FCoE:
switch(config)# system qos
switch(config-sys-qos)# service-policy type queuing input fcoe-default-in-policy
switch(config-sys-qos)# service-policy type queuing output fcoe-default-out-policy
switch(config-sys-qos)# service-policy type qos input fcoe-default-in-policy
switch(config-sys-qos)# service-policy type network-qos fcoe-default-nq-policy
Physical Fibre Channel Interfaces
Cisco Nexus devices support up to sixteen physical Fibre Channel (FC) uplinks through the use of two, optional
explansion modules. The first module contains eight FC interfaces. The second module includes four Fibre
Channel ports and four Ethernet ports.
Each Fibre Channel port can be used as a downlink (connected to a server) or as an uplink (connected to the
data center SAN network). The Fibre Channel interfaces support the following modes: E, F, NP, TE, TF,
TNP, SD, and Auto.
Virtual Fibre Channel Interfaces
Fibre Channel over Ethernet (FCoE) encapsulation allows a physical Ethernet cable to simultaneously carry
Fibre Channel and Ethernet traffic. In Cisco Nexus devices, an FCoE-capable physical Ethernet interface can
carry traffic for one virtual Fibre Channel (vFC) interface.
Like any interface in Cisco NX-OS, vFC interfaces are manipulable objects with properties such as configuration
and state. Native Fibre Channel and vFC interfaces are configured using the same CLI commands.
vFC interfaces support only F mode and operate in trunk mode only.
The following capabilities are not supported for virtual Fibre Channel interfaces:
• SAN port channels.
• The SPAN destination cannot be a vFC interface.
• Buffer-to-buffer credits.
• Exchange link parameters (ELP), or Fabric Shortest Path First (FSPF) protocol.
• Configuration of physical attributes (speed, rate, mode, transmitter information, MTU size).
• Port tracking.
VF Port
vFC interfaces always operate in trunk mode; vFC interfaces do not operate in any other mode. You can
configure allowed VSANs on a vFC by using the switchport trunk allowed vsan command under the vfc
interface (which is similar to FC TF and TE ports). For vFC interfaces that are connected to hosts, port VSAN
is the only VSAN that supports logins (FLOGI). We recommend that you restrict the allowed VSANs for
such vFC interfaces to the port VSAN by using the switchport trunk allowed vsan command in the interface
mode to configure a VF port.
Includes support for 160 vFC interfaces.
The vFC VSAN assignment and the global VLAN-to-VSAN mapping table enables the Cisco Nexus device
to choose the appropriate VLAN for a VF port.
Cisco Nexus 5000 Series NX-OS SAN Switching Configuration Guide, Release 5.2(1)N1(1)
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Configuring Fibre Channel Interfaces
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