Cisco Systems 3750E Enabling Udld on an Interface, Resetting an Interface Disabled by Udld, 29-6

Chapter 29 Configuring UDLD

Configuring UDLD

Enabling UDLD on an Interface

Beginning in privileged EXEC mode, follow these steps either to enable UDLD in the aggressive or normal mode or to disable UDLD on a port:

	Command	Purpose
Step 1
	configure terminal	Enter global configuration mode.
Step 2
	interface interface-id	Specify the port to be enabled for UDLD, and enter interface
		configuration mode.
Step 3
	udld port [aggressive]	UDLD is disabled by default.
		Note When a switch joins a switch stack, it retains its
		interface-specific UDLD settings.
		• udld port—Enables UDLD in normal mode on the specified port.
		• udld port aggressive—Enables UDLD in aggressive mode on the
		specified port.
		Note Use the no udld port interface configuration command to
		disable UDLD on a specified fiber-optic port.
		For more information about aggressive and normal modes, see the
		“Modes of Operation” section on page 29-1.
Step 4
	end	Return to privileged EXEC mode.
Step 5
	show udld interface-id	Verify your entries.
Step 6
	copy running-config startup-config	(Optional) Save your entries in the configuration file.

Resetting an Interface Disabled by UDLD

Beginning in privileged EXEC mode, follow these steps to reset all ports disabled by UDLD:

Command

Step 1 udld reset

Step 2 show udld

Purpose

Reset all ports disabled by UDLD.

Verify your entries.

You can also bring up the port by using these commands:

•The shutdown interface configuration command followed by the no shutdown interface configuration command restarts the disabled port.

•The no udld {aggressive enable} global configuration command followed by the udld {aggressive enable} global configuration command re-enables the disabled ports.

•The no udld port interface configuration command followed by the udld port [aggressive] interface configuration command re-enables the disabled fiber-optic port.

•The errdisable recovery cause udld global configuration command enables the timer to automatically recover from the UDLD error-disabled state, and the errdisable recovery interval interval global configuration command specifies the time to recover from the UDLD error-disabled state.

Catalyst 3750-E and 3560-E Switch Software Configuration Guide

29-6 OL-9775-02