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CISCO IOS in a Nutshell
book

CISCO IOS in a Nutshell

by James Boney
December 2001
Intermediate to advanced
608 pages
25h 14m
English
O'Reilly Media, Inc.
Content preview from CISCO IOS in a Nutshell

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: 156592942XCatalog PageErrata