Switch diagnostic chart Use the following chart (page 2) to record/diagnose faulty ports on a switch. This chart is intended for IT professionals who work hands-on with server/networking equipment in a corporate environment, though its use is not limited to the aforementioned scenario. As the creator of this resource, I recommend printing it out for quick reference while on-the-job, but this is of course optional. Recommended use: use a highlighter to fill in the square corresponding to a given port if the port is confirmed functional. Use a different colored pen/Sharpie to fill in the squares for faulty ports.