In addition to POST, Fabric OS includes diagnostic tests to help you troubleshoot the hardware and firmware. This includes tests of internal connections and circuitry, fixed media, and the transceivers and cables in use. The tests are implemented by command, either through a Telnet session or through a terminal set up for a serial connection to the Extension Switch. Some tests require the ports to be connected by external cables, to allow diagnostics to verify the serializer/deserializer interface, transceiver, and cable. Some tests require loop back plugs.
Diagnostic tests are run at link speeds of 1-Gbps, 2-Gbps, 4-Gbps, and 8-Gbps. For information about specific diagnostic tests, see the Brocade Fabric OS Administration Guide.