Loop a Particular T1 Channel towards the Network

Purpose

Creating a loop from a particular T1 interface to the network allows the transport-layer engineer to test the T1 interface from various points in the network and isolate the problem.

Action

To create a loop from a particular T1 interface to the network, follow these steps:

1. In configuration mode, go to the following hierarchy level:

[edit]

user@host# edit interfaces interface-name t1-options

2. Configure the loopback:

[edit interfaces interface-name t1-options]

user@host# set loopback remote

3. Verify the configuration:

user@host# show

For example:

[edit interfaces ds-2/1/1:0:0 t1-options]

user@host# show 

loopback remote;

4. Commit the configuration:

user@host# commit

What It Means

This command loops any traffic from the network back into the network. The interface name is one of the following:

• Channel group 0 for the particular T1 channel on the Multichannel DS-3 port for a channelized DS-3 to DS-3 interface (for example, ds-2/1/1:2:0)
• Particular T1 channel on the Multichannel DS-3 port for a channelized DS-3 to DS-1 interface (for example, t1-2/1/1:3)