Connectrix B-Series ClearLink Diagnostic Port

Wondering if anyone has used the ClearLink Diagnostic Port on their Connectrix B-Series switches.  Any success stories  or experiences that you can share???

Clearlink Diagnostic Port (D_Port) mode allows you to convert a Fibre Channel port into a diagnostic port for testing link traffic and running electrical loopback and optical loopback tests.  The test results can be very useful in diagnosing a variety of port and link problems.