Performing Troubleshooting and Diagnostic Tests7-12Group 2 and Group 3 Test SetupTo run the Group 2 and Group 3 diagnostic tests, you need:n The EtherDisk diskette.n Loopback plug for the Group 2 test. If you are testingthe 3C509, 3C509-COMBO, or 3C579 adapter, youcan use a coax loopback plug or connect to an inactivenetwork. The plug can be ordered from 3Com. Thereare no loopback tests for TP adapters.n A second computer set up as an echo server for theGroup 3 test.CAUTION: Do not use an active network to run theGroup 2 or Group 3 tests.Group 2 TestThe Group 2 test is called the Network Loopback Test.It tests the adapter’s ability to transmit and receive dataover the network. This test requires installation of aloopback plug at the adapter’s transceiver connection.Or, you can run the test on an inactive network.Connecting a Loopback PlugFollow these steps:1. Connect the loopback plug to the round BNCconnector on the back of the 3C509,3C509-COMBO, or 3C579 adapter.2. Enable the Group 2 test from the Test Setupdialog box. Highlight and press [Enter].3. Go to the Run dialog box to start the tests.
