Cisco Nexus 6000 Series NX-OS Interfaces Command Reference
U Commands
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U Commands

Table Of Contents

U Commands

udld (Ethernet)

U Commands

This chapter describes the Cisco NX-OS interface commands that begin with U.

udld (Ethernet)

To enable and configure the Unidirectional Link Detection (UDLD) protocol on an Ethernet interface, use the udld command. To disable UDLD, use the no form of this command.

udld {aggressive | disable | enable}

no udld {aggressive | disable | enable}

Syntax Description


Enables UDLD in aggressive mode on the interface.


Disables UDLD on the interface.


Enables UDLD in normal mode on the interface.

Command Default


Command Modes

Interface configuration mode

Command History



This command was introduced.

Usage Guidelines

You can configure normal or aggressive UDLD modes for an Ethernet interface. Before you can enable a UDLD mode for an interface, you must make sure that UDLD is enabled on the switch. UDLD must also be enabled on the other linked interface and its device.

To use the normal UDLD mode on a link, you must configure one of the ports for normal mode and configure the port on the other end for the normal or aggressive mode. To use the aggressive UDLD mode, you must configure both ends of the link for aggressive mode.


This example shows how to enable the normal UDLD mode for an Ethernet port:

switch# configure terminal
switch(config)# interface ethernet 1/1
switch(config-if)# udld enable

This example shows how to enable the aggressive UDLD mode for an Ethernet port:

switch(config-if)# udld aggressive

This example shows how to disable UDLD for an Ethernet port:

switch(config-if)# udld disable

Related Commands


show udld

Displays the administrative and operational UDLD status.