Configure a Local Loopback

Action

To configure a local loopback, follow these steps:

1. In configuration mode, go to the following hierarchy level, depending on whether you are configuring a full T3 or T1 interface:

[edit]

user@host# edit interfaces interface-name (t3-options | t1-options)

2. Configure the local loopback:

[edit interfaces interface-name (t3-options | t1-options)]

user@host# set loopback local

The following is an example of the name for a T1 channel 0, group 0, on a Multichannel DS-3 port for a channelized DS-3 to DS-0 interface:

[edit interfaces ds-2/1/0:0:0 t3-options]

   
NOTE: In order to configure T3 options on the Multichannel DS-3, you configure the first logical interfaces: ds-2/1/0:0:0 t3-options.


 

The following is an example of the name for a T1 channel on a Multichannel DS-3 port for a channelized DS-3 to DS-1 interface:

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

3. Verify the configuration:

user@host# show

For example:

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

user@host# show   

loopback local;

4. Commit the configuration:

user@host# commit

For example:

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

user@host# commit 

commit complete

What It Means

When you create a local loopback, you create an internal loop on the interface being tested. A local loopback loops the traffic internally on that PIC. A local loopback tests the interconnection of the PIC but does not test the transmit and receive ports.

NOTE: Remember to delete the loopback statement after completing the test.