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Cisco IOS in a Nutshell, 2nd Edition
book

Cisco IOS in a Nutshell, 2nd Edition

by James Boney
August 2005
Intermediate to advanced content levelIntermediate to advanced
798 pages
31h 12m
English
O'Reilly Media, Inc.
Content preview from Cisco IOS in a Nutshell, 2nd Edition

Name

down-when-looped — interface

Synopsis

down-when-looped
no down-when-looped

Configures

Loopback detection

Default

Disabled

Description

This command tells the interface to go down when a loopback is detected. The default behavior is for the interface to remain up when the device is placed in loopback, so you can place a DCE device such as a CSU/DSU in loopback and ping the interface. This allows you to test the cable between the router and the DCE device.

Use the no form of this command to disable this behavior. If this command is given, the interface shuts down when the DCE device (CSU/DSU) is placed in loopback mode.

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Publisher Resources

ISBN: 0596008694Errata