Configuring FCoE VLANs and Virtual Interfaces

This chapter describes how to configure Fibre Channel over Ethernet (FCoE) VLANs and virtual interfaces on Cisco Nexus 5000 Series switches. It contains the following sections:

Information About Virtual Interfaces

Cisco Nexus 5000 Series switches support Fibre Channel over Ethernet (FCoE), which allows Fibre Channel and Ethernet traffic to be carried on the same physical Ethernet connection between the switch and the servers.

The Fibre Channel portion of FCoE is configured as a virtual Fibre Channel interface. Logical Fibre Channel features (such as interface mode) can be configured on virtual Fibre Channel interfaces.

A virtual Fibre Channel interface must be bound to an interface before it can be used. The binding is to a physical Ethernet interface (when the converged network adapter (CNA) is directly connected to the Cisco Nexus 5000 Series switch), a MAC address (when the CNA is remotely connected over a Layer 2 bridge), or an EtherChannel when the CNA connects to the Fibre Channel Forwarder (FCF) over a virtual port channel (vPC).

Guidelines and Limitations for FCoE VLANs and Virtual Interfaces

Follow these guidelines and limitations when configuring FCoE VLANs and Virtual Interfaces:

  • Each virtual Fibre Channel interface must be bound to an FCoE-enabled Ethernet or EtherChannel interface or to the MAC address of a remotely connected adapter. FCoE is supported on 10-Gigabit Ethernet interfaces.

    The Ethernet or EtherChannel interface that you bind the virtual Fibre Channel interface to must be configured as follows:

    • The Ethernet or EtherChannel interface must be a trunk port (use the switchport mode trunk command).

    • The FCoE VLAN that corresponds to a virtual Fibre Channel’s VSAN must be in the allowed VLAN list.

    • You must not configure an FCoE VLAN as the native VLAN of the trunk port.


      Note

      The native VLAN is the default VLAN on a trunk. Any untagged frames transit the trunk as native VLAN traffic.

    • You should use an FCoE VLAN only for FCoE.

    • Do not use the default VLAN, VLAN1, as an FCoE VLAN.

    • You must configure the Ethernet interface as PortFast (use the spanning-tree port type edge trunk command).


      Note

      You are not required to configure trunking on the server interface even if the switch interface is configured with trunking enabled. All non-FCoE traffic from the server will be passed on the native VLAN.

  • Each virtual Fibre Channel interface is associated with only one VSAN.

  • You must map any VSAN with associated virtual Fibre Channel interfaces to a dedicated FCOE-enabled VLAN.

  • FCoE is not supported on private VLANs.

  • If the converged access switches (in the same SAN fabric or in another) need to be connected to each other over Ethernet links for a LAN alternate path, then you must explicitly configure such links to exclude all FCoE VLANs from membership.

  • You must use separate FCoE VLANs for FCoE in SAN-A and SAN-B fabrics.

  • FCoE connectivity to pre-FIP CNAs over virtual port channels (vPCs) is not supported.


Note

Virtual interfaces are created with the administrative state set to down. You must explicitly configure the administrative state to bring the virtual interface into operation.

Configuring Virtual Interfaces

Mapping a VSAN to a VLAN

A unique, dedicated VLAN must be configured at every converged access switch to carry traffic for each Virtual Fabric (VSAN) in the SAN (for example, VLAN 1002 for VSAN 1, VLAN 1003 for VSAN 2, and so on). If MST is enabled, a separate MST instance must be used for FCoE VLANs.

SUMMARY STEPS

    1.    switch# configure terminal

    2.    switch(config)# vlan vlan-id

    3.    switch(config-vlan)# fcoe [vsan vsan-id]

    4.    switch(config-vlan)# exit


DETAILED STEPS
     Command or ActionPurpose
    Step 1 switch# configure terminal
     

    Enters configuration mode.

     
    Step 2 switch(config)# vlan vlan-id
     

    Enters VLAN configuration mode. The VLAN number range is from 1 to 4096.

     
    Step 3 switch(config-vlan)# fcoe [vsan vsan-id]
     

    Enables FCoE for the specified VLAN. If you do not specify a VSAN number, a mapping is created from this VLAN to the VSAN with the same number.

    Configures the mapping from this VLAN to the specified VSAN.

     
    Step 4 switch(config-vlan)# exit
     

    Exits VLAN configuration mode.

     

    This example shows how to map VLAN 200 to VSAN 2: 

    switch(config)# vlan 200
    switch(config-vlan)# fcoe vsan 2

    Creating a Virtual Fibre Channel Interface

    You can create a virtual Fibre Channel interface. You must bind the virtual Fibre Channel interface to a physical interface before it can be used.

    SUMMARY STEPS

      1.    switch# configure terminal

      2.    switch(config)# interface vfc vfc-id

      3.    switch(config-if)# bind {interface {ethernet slot/port | port-channel channel-number} | mac-address MAC-address}

      4.    (Optional) switch(config-if)# no bind {interface {ethernet slot/port | port-channel channel-number} | mac-address MAC-address}

      5.    (Optional) switch(config)# no interface vfc vfc-id


    DETAILED STEPS
       Command or ActionPurpose
      Step 1 switch# configure terminal
       

      Enters configuration mode.

       
      Step 2 switch(config)# interface vfc vfc-id
       

      Creates a virtual Fibre Channel interface (if it does not already exist) and enters interface configuration mode.

      The virtual Fibre Channel interface ID range is from 1 to 8192.

       
      Step 3 switch(config-if)# bind {interface {ethernet slot/port | port-channel channel-number} | mac-address MAC-address}
       

      Binds the virtual Fibre Channel interface to the specified interface.

       
      Step 4 switch(config-if)# no bind {interface {ethernet slot/port | port-channel channel-number} | mac-address MAC-address}
              		(Optional)

      Unbinds the virtual Fibre Channel interface from the specified interface.

       
      Step 5 switch(config)# no interface vfc vfc-id
              		(Optional)

      Deletes a virtual Fibre Channel interface.

       

      This example shows how to bind a virtual Fibre Channel interface to an Ethernet interface: 

      switch# configure terminal
      switch(config)# interface vfc 4
      switch(config-if)# bind interface ethernet 1/4

      This example shows how to bind a virtual Fibre Channel interface to create a vPC: 

      switch# configure terminal
      switch(config)# interface vfc 3
      switch(config-if)# bind interface port-channel 1

      This example shows how to bind a virtual Fibre Channel interface to a MAC address: 

      switch# configure terminal
      switch(config)# interface vfc 2
      switch(config-if)# bind mac-address 00:0a:00:00:00:36

      This example shows how to delete a virtual Fibre Channel interface: 

      switch# configure terminal
      switch(config)# no interface vfc 4

      Associating a Virtual Fibre Channel Interface to a VSAN

      A unique, dedicated VLAN must be configured at every converged access switch to carry traffic for each Virtual Fabric (VSAN) in the SAN (for example, VLAN 1002 for VSAN 1, VLAN 1003 for VSAN 2, and so on). If MST is enabled, a separate MST instance must be used for FCoE VLANs.

      SUMMARY STEPS

        1.    switch# configure terminal

        2.    switch(config)# vsan database

        3.    switch(config-vsan)# vsan vsan-id interface vfc vfc-id

        4.    (Optional) switch(config-vsan)# no vsan vsan-id interface vfc vfc-id


      DETAILED STEPS
         Command or ActionPurpose
        Step 1 switch# configure terminal
         

        Enters configuration mode.

         
        Step 2switch(config)# vsan database
         

        Enters VSAN configuration mode.

         
        Step 3switch(config-vsan)# vsan vsan-id interface vfc vfc-id
         

        Configures the association between the VSAN and virtual Fibre Channel interface.

        The VSAN number must map to a VLAN on the physical Ethernet interface that is bound to the virtual Fibre Channel interface.

         
        Step 4switch(config-vsan)# no vsan vsan-id interface vfc vfc-id
                  		(Optional)

        Disassociates the connection between the VSAN and virtual Fibre Channel interface.

         

        This example shows how to associate a virtual Fibre Channel interface to a VSAN: 

        switch# configure terminal
        switch(config)# vsan database
        switch(config-vsan)# vsan 2 interface vfc 4

        Verifying the Virtual Interface

        To display configuration information about virtual interfaces, perform one of the following tasks:

        Command

        Purpose

        switch# show interface vfc vfc-id

        Displays the detailed configuration of the specified Fibre Channel interface.

        switch# show interface brief

        Displays the status of all interfaces.

        switch# show vlan fcoe

        Displays the mapping of FCoE VLANs to VSANs.

        This example shows how to display a virtual Fibre Channel interface bound to an Ethernet interface: 

        switch# show interface vfc 3
        vfc3 is up
            Bound interface is Ethernet1/37
            Hardware is Virtual Fibre Channel
            Port WWN is 20:02:00:0d:ec:6d:95:3f
            Admin port mode is F, trunk mode is on
            snmp link state traps are enabled
            Port mode is F, FCID is 0x490100
            Port vsan is 931
            1 minute input rate 0 bits/sec, 0 bytes/sec, 0 frames/sec
            1 minute output rate 0 bits/sec, 0 bytes/sec, 0 frames/sec
              0 frames input, 0 bytes
                0 discards, 0 errors
              0 frames output, 0 bytes
                0 discards, 0 errors
            Interface last changed at Thu May 21 04:44:42 2009

        This example shows how to display a virtual Fibre Channel interface bound to a MAC address: 

        switch# show interface vfc 1001
        vfc1001 is down
            Bound MAC is 00:0a:00:00:00:01
            Hardware is Virtual Fibre Channel
            Port WWN is 23:e8:00:0d:ec:6d:95:3f
            Admin port mode is F, trunk mode is on
            snmp link state traps are enabled
            Port vsan is 901
            1 minute input rate 0 bits/sec, 0 bytes/sec, 0 frames/sec
            1 minute output rate 0 bits/sec, 0 bytes/sec, 0 frames/sec
              0 frames input, 0 bytes
                0 discards, 0 errors
              0 frames output, 0 bytes
                0 discards, 0 errors

        This example shows how to display the status of all the interfaces on the switch (some output has been removed for brevity): 

        switch# show interface brief
        -------------------------------------------------------------------------------
        Interface  Vsan   Admin  Admin   Status          SFP    Oper  Oper   Port
                          Mode   Trunk                          Mode  Speed  Channel
                                 Mode                                 (Gbps)
        -------------------------------------------------------------------------------
        fc3/1      1      auto   on      trunking         swl    TE      2    --
        fc3/2      1      auto   on      sfpAbsent        --     --           --
        ...
        fc3/8      1      auto   on      sfpAbsent        --     --           --
        -------------------------------------------------------------------------------
        Interface                Status     IP Address        Speed    MTU   Port
                                                                             Channel
        -------------------------------------------------------------------------------
        Ethernet1/1              hwFailure  --                --       1500  --
        Ethernet1/2              hwFailure  --                --       1500  --
        Ethernet1/3              up         --                10000    1500  --
        ...
        Ethernet1/39             sfpIsAbsen --                --       1500  --
        Ethernet1/40             sfpIsAbsen --                --       1500  --
        -------------------------------------------------------------------------------
        Interface                Status     IP Address        Speed    MTU
        -------------------------------------------------------------------------------
        mgmt0                    up         172.16.24.41      100      1500
        -------------------------------------------------------------------------------
         
        -------------------------------------------------------------------------------
        Interface  Vsan   Admin  Admin   Status          SFP    Oper  Oper   Port
                          Mode   Trunk                          Mode  Speed  Channel
                                 Mode                                 (Gbps)
        -------------------------------------------------------------------------------
        vfc 1        1      F      --      down             --     --           --
        ...

        This example shows how to display the mapping between the VLANs and VSANs on the switch: 

        switch# show vlan fcoe
        VLAN      VSAN      Status
        --------  --------  --------
        15        15        Operational
        20        20        Operational
        25        25        Operational
        30        30        Non-operational

        Mapping VSANs to VLANs Example Configuration

        The following example shows how to configure the FCoE VLAN and a virtual Fibre Channel interface:

        SUMMARY STEPS

          1.    Configure the VLAN on a physical Ethernet address.

          2.    Create a virtual Fibre Channel interface and bind it to a physical Ethernet interface.

          3.    Enable the associated VLAN and map the VLAN to a VSAN.

          4.    Associate the virtual Fibre Channel interface to the VSAN.


        DETAILED STEPS
          Step 1   Configure the VLAN on a physical Ethernet address. 
          switch# configure terminal
          switch(config)# interface ethernet 1/4
          switch(config-if)# spanning-tree port type edge trunk
          switch(config-if)# switchport mode trunk
          switch(config-if)# switchport trunk allowed vlan 1,200
          switch(config-if)# exit
          Step 2   Create a virtual Fibre Channel interface and bind it to a physical Ethernet interface. 
          switch(config)# interface vfc 4
          switch(config-if)# bind interface ethernet 1/4
          switch(config-if)# exit
          Step 3   Enable the associated VLAN and map the VLAN to a VSAN. 
          switch(config)# vlan 200
          switch(config-vlan)# fcoe vsan 2
          switch(config-vlan)# exit
          Step 4   Associate the virtual Fibre Channel interface to the VSAN. 
          switch(config)# vsan database
          switch(config-vsan)# vsan 2 interface vfc 4
          switch(config-vsan)# exit