Step 1: Create a Loop from the Router to the Network

Purpose

Creating a loop from the router to the network allows the transport-layer engineer to test the router from various points in the network. This helps the engineer isolate where the problem might be located. Figure 10 illustrates a loop from a router to the network.

Figure 10: Loop from the Router to the Network

Action

To create a loop from the router to the network, follow these steps:

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

[edit]

user@host# edit interfaces interface-name (sonet-options | t3-options)

2. Configure the remote loopback:

[edit interfaces interface-name (sonet-options | t3-options)]

user@host# set loopback remote

3. Verify the configuration:

user@host# show

For example:

[edit interfaces t3-1/0/0 t3-options]

user@host# show

loopback remote;

4. Commit the change:

user@host# commit 

For example:

[edit interfaces t3-1/0/0 t3-options]

user@host# commit 

commit complete

What It Means

This command loops any traffic from the network back into the network.