Running diagnostic tests

In addition to the POST, switch firmware includes diagnostic tests to help you troubleshoot the hardware and firmware. These diagnostics test the internal connections and circuitry, the fixed media, and the transceivers and cables in use.

The tests are implemented by command, either through an SSH session or through a terminal setup for a serial connection to the device. Some tests require that the ports be connected by external cables to allow diagnostics to verify the serializer or deserializer interface, transceiver, and cable. Some tests require loopback plugs.

Diagnostic tests are run at supported link speeds depending on the speed of the link being tested and the type of port.