F Commands

feature adapter-fex

To enable the Adapter Fabric Extender (Adapter-FEX), use the feature adapter-fex command. To disable Adapter-FEX, use the no form of this command.

feature adapter-fex

no feature adapter-fex

Syntax Description

This command has no arguments or keywords.

Command Default

Disabled

Command Modes

Global configuration mode

Command History

Release

Modification

5.1(3)N1(1)

This command was introduced.

Usage Guidelines

Before you disable this feature on the switch, do the following:

  • Remove all virtual Ethernet interface configurations on the switch.
  • Remove all port profiles of type vethernet.
  • Change the port mode to access by using the switchport mode access command.

If you attempt to disable the Adapter-FEX feature with virtual Ethernet interface or port profile configurations enabled, the switch returns an error message.

Before you use a virtual Ethernet interface, you must enable Cisco Virtual Machine Fabric Extender (VM-FEX) on the switch by using the feature vmfex command.

Examples

This example shows how to enable Adapter-FEX on the switch: 

switch# configure terminal
switch(config)# feature adapter-fex
Virtualization Plugin license checked out successfully
Virtualization Plugin extracted successfully
All Virtualization processes enabled successfully
switch(config)#

This example shows how to disable Adapter-FEX on the switch: 

switch# configure terminal
switch(config)# no feature adapter-fex
Disabled feature adapter-fex successfully.
You should save the configuration and Reload.
switch(config)#

This example shows the error message that appears when you attempt to disable Adapter-FEX on a switch with virtual Ethernet interface configurations enabled: 

switch# configure terminal
switch(config)# no feature adapter-fex
Disabling of NIV failed.veth and vntag configs found
Shutdown all veths and Remove them.
Change ports with 'switchport mode vntag' to 'switchport mode access'.
switch(config)#

Related Commands

Command

Description

interface vethernet

Configures a virtual Ethernet interface.

port-profile

Configures a port profile.

show feature

Displays whether or not Adapter-FEX is enabled on the switch.

switchport mode

Configures the interface as a nontrunking nontagged single-VLAN Ethernet interface.

feature lldp

The Link Layer Discovery Protocol (LLDP), which is a neighbor discovery protocol that is used for network devices to advertise information about themselves to other devices on the network, is enabled on the switch by default.

feature lldp

no feature lldp

Syntax Description

This command has no arguments or keywords.

Command Default

Enabled

Command Modes

Global configuration mode

Command History

Release

Modification

4.0(0)N1(1a)

This feature was introduced.

Usage Guidelines

You cannot enable or disable LLDP on a Cisco Nexus 5000 Series switch. LLDP is enabled on the switch by default. However, the feature lldp command shows as part of the running configuration on the switch, as shown below: 

switch# show running-config
 
!Command: show running-config
!Time: Tue Feb 10 12:36:03 2009
version 5.0(3)N1(1)
feature telnet
feature lldp
username admin password 5 $1$d8lkfqC8$4VfRuOoZTKvCtTq8VAKbq/  role network-admin
no password strength-check
ip domain-lookup
hostname switch
class-map type qos class-fcoe
class-map type qos match-all c1
  match cos 1
<--Output truncated-->
switch#

Beginning with Cisco NX-OS Release 4.0(0)N1(1a) and up to Release 5.0(2)N1(1), the Book Title included the feature lldp command.

The Cisco Discovery Protocol (CDP) is a device discovery protocol that runs over Layer 2 (the data link layer) on all Cisco-manufactured devices (routers, bridges, access servers, and switches). CDP allows network management applications to automatically discover and learn about other Cisco devices connected to the network.

To support non-Cisco devices and to allow for interoperability between other devices, the switch supports the Link Layer Discovery Protocol (LLDP). LLDP is a neighbor discovery protocol that is used for network devices to advertise information about themselves to other devices on the network. This protocol runs over the data-link layer, which allows two systems running different network layer protocols to learn about each other.

Examples

This example shows how to enable LLDP on the switch: 

switch(config)# feature lldp
 
switch(config)#

This example shows how to disable LLDP on the switch: 

switch(config)# no feature lldp
 
switch(config)#

Related Commands

Command

Description

lldp

Configures the global LLDP options on the switch.

lldp (Interface)

Configures the LLDP feature on an interface.

show feature

Displays that LLDP is enabled on the switch.

feature poe

To enable Power over Ethernet (PoE), use the feature poe command. To disable PoE, use the no form of this command.

feature poe

no feature poe

Syntax Description

This command has no keywords or arguments.

Command Default

Disabled

Command Modes

Global configuration mode

Command History

Release

Modification

5.0(3)N2(1)

This command was introduced.

Examples

This example shows how to enable PoE on the switch: 

switch(config)# feature poe

Related Commands

Command

Description

power inline

Configures the power usage for interfaces.

show feature

Displays the status of features enabled or disabled on the switch.

feature udld

To enable the Cisco-proprietary Unidirectional Link Detection (UDLD) protocol, which allows ports that are connected through fiber optics or copper Ethernet cables to monitor the physical configuration of the cables and detect when a unidirectional link exists, use the feature udld command. To disable UDLD on the switch, use the no form of this command.

feature udld

no feature udld

Syntax Description

This command has no arguments or keywords.

Command Default

UDLD is disabled.

Command Modes

Global configuration mode

Command History

Release

Modification

4.0(1a)N1(1)

This command was introduced.

Examples

This example shows how to enable UDLD on the switch: 

switch(config)# feature udld

Related Commands

Command

Description

show udld

Displays the administrative and operational UDLD status.

show feature

Displays whether or not UDLD is enabled on the switch.