#Loopback plug to test an ethernet port series

On Total Access Units and NetVanta 6000 Units, these ports are built in by default. Slots are numbered left to right and the ports are numbered left to right on the individual NIMs in each slot. Note: If you do not know the and numbers in the above command, examine the back of your unit. In this example, this would need to be set back to line after the completion of the test. Notice in the above output, the clock source is set to line. If this is not done, the T1 interface could take errors from clock-slips or clock mismatching between the separate ends of the T1 connection. This may need to be changed during the loopback test so it is important to take note of the setting before starting the test as to make sure it is set back correctly afterward. If you have multiple T1s linked together in the same PPP or Frame-relay bundle, this will just result in loss in the bandwidth of the individual T1 you are testing and not your entire network connection.īefore beginning the test, use the show run interface t1 command to view the current clock setting on the interface. To run the T1 loopback test, you will need to unplug the T1 connection from the network, meaning that any services that use it will be down for the entirety of the testing. For help accessing the AOS unit's CLI, please see the. However, it is considered beginner level as it only requires a few simple commands. The T1 Loopback test can only be administered using the CLI. If this is not possible, you can contact ADTRAN Technical Support and a loopback plug can be provided. One can be made from a piece of Ethernet cable using the document. To perform this test, a T1 'loopback plug' is required. Please see the for products that support a NIM interface or built in T1 modules.Ī loopback test is performed by sending a quasi-random test pattern from the router and looping it physically back to its own receive lines.

#Loopback plug to test an ethernet port series

The T1 Loopback test is only relevant to units utilizing a T1 or E1 interface that has been inserted into a Network Interface Module (NIM) slot or a built in T1 interface on a Total Access or NetVanta 6000 Series unit. Resetting the Unit Back to Normal Operation.Important Considerations Before Running the Test.Performing the Loopback Test Using the CLI However, this document does also apply to the E1 as well provided you substitute the 'T1' in the commands given with 'E1'.Įquipment Needed to Perform Loopback Test Note: The E1 is a international equivalent of the T1 interface with some slight differences. If you would like to a video demonstrating the troubleshooting steps in this document, please see. If provisioning a T1 connection for the first time, please see the Useful Links section of this document to find the proper document to verify your configuration. It is recommended that prior to using this document, you read the document to make sure you understand what types of problems with a T1 warrant consideration of the ADTRAN hardware as a possible issue. By running a quasi-random pattern through the T1 interface, a user can see with certainty if the unit is functioning properly while segmented from the rest of the T1 connection from the provider. When a T1 connection does not seem to be working properly, the most efficient way to troubleshoot the router's physical T1 interface is to run a T1 Loopback Test. A T1 interface provides guaranteed bandwidth and does not have the distance limitations of other protocols making it ideal for certain networks. While high-speed, efficient, and low price Ethernet and fiber lengths have started to become more of the norm in modern networks, the T1 link is still commonplace at many businesses because of its advantages over Ethernet.