Information About Virtual Interfaces
Cisco Nexus devices 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 device), 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).
Information About Shutting Down LAN Traffic
Converged Network Adapters (CNA) enable both FCoE and LAN traffic (Unified I/O) to co-exist over a physical link.
In vPC configurations with CNAs, network parameters need to be consistent across peer switches. If the system detects an inconsistency, the secondary vPC leg goes down. Since vPC legs carry both FCOE and LAN traffic, the FCoE link goes down also.
To avoid having the FCoE link go down in this situation, you can use the shutdown lan command to shutdown only the LAN traffic on port-channels and individual Ethernet ports.
Note |
When vPC triggers the vPC secondary leg to be brought down, only the Ethernet VLANs are brought down for the secondary vPC leg. FCoE/storage VLANs of the secondary vPC leg remain up. |
Notes About the shutdown lan Command
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The shutdown lan command is only configurable on port-channel interfaces, FEX HIF ports, or on individual Ethernet interfaces that vFC interfaces are bound upon.
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The shutdown lan command is only configurable on port-channel interfaces or on individual Ethernet interfaces that are in an operational trunking state.
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The shutdown lan command cannot be enabled on the secondary vPC leg, if the vPC enabled shutdown lan is applied on the secondary vPC leg.
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A vPC enabled shutdown LAN is not operable if the shutdown lan command is applied on the secondary vPC leg.
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The shutdown lan command is not configurable on port-channel members.
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The shutdown lan command default is no shutdown lan (shutdown lan is disabled).
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The shutdown lan command has a prerequisite that the Link Layer Discovery Protocol (LLDP) feature be enabled.
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A port with a shutdown LAN configuration enabled cannot be added to a port channel.
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The shutdown LAN enable/disable configuration is on a per interface basis.
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If a shutdown lan is configured on an interface, a no shut command on the interface does not bring up LAN VLANs.
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A shutdown LAN is triggered when a Type-1 inconsistency occurs in a VPC network.
Examples of Shutdown LAN Traffic
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Shutdown the LAN traffic on port-channel.
switch(config)#interface port-channel 955 switch(config-if)# shutdown lan
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Shutdown the LAN traffic on individual Ethernet port.
switch(config)#interface Ethernet 2/5 switch(config-if)# shutdown lan
Examples of Verifying Shutdown LAN Traffic
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Verifying when the shutdown lan command is issued on port-channel 955 with Ethernet interface 2/5 as member.
switch# sh interface port-channel 955 | grep LAN All LAN VLANs are administratively shut switch# sh interface ethernet 2/5 | grep LAN All LAN VLANs are administratively shut switch# sh run interface port-channel 955 | grep shut shutdown lan switch# sh run interface e2/5 | grep shut shutdown lan
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Verifying when the vPC triggers shutdown LAN on the secondary vPC leg (port-channel 231 with Ethernet 2/31 as member).
switch# sh interface port-channel 231 | grep LAN All LAN VLANs are administratively shut