We have quite a few Nortel Ethernet Routing Switch 5500s deployed throughout our organization. There’s a great new benefit in using the new hardware to help us test the cable plant remotely.
Here’s the text from the Nortel manual;
Testing cables with the Time Domain Reflectometer
With Release 5.0 software, the Nortel Ethernet Routing Switch 5500 Series is equipped with a Time Domain Reflectometer (TDR). The TDR provides a diagnostic capability to test connected cables for defects (such as short pin and pin open). You can obtain TDR test results from the CLI or the JDM. The cable diagnostic tests only apply to Ethernet copper ports; fiber ports cannot be tested. You can initiate a test on multiple ports at the same time. When you test a cable with the TDR, if the cable has a 10/100 MB/s link, the link is broken during the test and restored only when the test is complete. Use of the TDR does not affect 1 GB/s links.
Note: The accuracy margin of cable length diagnosis is between three to five meters. Nortel suggests the shortest cable for length information be five meters long.
Unfortunately this feature is ONLY available on the 5510, 5520 and 5530 switches.
Using Device Manager you’ll find the option on the port settings (a tab to the right labeled “TDR”). You can also use the following CLI commands;
tdr test <portlist> show tdr <portlist>