If you are implementing or maintaining a network, it is almost certain that at some point something will go wrong. This could be a result of human error (for example, a misconfiguration issue), hardware failure, or a software problem. In such circumstances, your troubleshooting skills will be put to the test. The aim of this chapter is to help you develop your troubleshooting skills, by discussing both some common networking problems and the tools that can be used to diagnose them.

The following topics will be covered in this chapter:

• Troubleshooting basics
• pfSense troubleshooting tools