CCNA Discovery 1, Chapter 9

9.1.1: One key to success in troubleshooting is to use proper documentation. A good troubleshooter might document the problem, the steps taken to determine the cause, and the steps to correct the problem. Detailed documentation of successful and unsuccessful troubleshooting can prove a valuable reference for later situations.

9.1.2: When you encounter a network problem, the first step is to gather information. Ask the individual who reported the problem to identify recent actions and symptoms, refer to any existing documentation about the involved equipment, and use any available network monitoring tools to view logs and recent network activity.

9.1.3: The following points outline possible approaches for a troubleshooting process with a layered concept of networking: