Hardware manual

loopback dte
Interface Commands IR-143
loopback dte
To loop packets back to the DTE from the CSU/DSU, when the device supports this feature, use the
loopback interface configuration command. To remove the loop, use the no form of this command.
loopback dte
no loopback dte
Syntax Description
This command has no arguments or keywords.
Default
Disabled
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
This command is useful for testing the DTE-to-DCE cable.
This command is used to test the performance of the integrated CSU/DSU. Packets are looped from
within the CSU/DSU back to the serial interface of the router. Send a test ping to see if the packets
successfully looped back. To cancel the loopback test, use the no loopback dte command.
When using the 4-wire 56/64-kbps CSU/DSU module, an out-of-service signal is transmitted to the
remote CSU/DSU.
To show interfaces currently in loopback operation, use the show interfaces loopback EXEC
command.
Example
The following example configures the loopback test on the DTE interface:
router(config)# interface serial 0
router(config-if)# loopback dte
router(config-if)#
Related Commands
You can use the master indexes or search online to find documentation of related commands.
show interfaces loopback