|  | 7.3 | Troubleshooting Networks
| 7.3.1 | Problem solving
Problems happen! Even when the network is monitored, the equipment is reliable, and the users are careful, things may go wrong. The test of a good network administrator is the ability to analyze, troubleshoot, and correct problems under pressure of a network failure that causes company downtime. Good network administration techniques were described in Semester 3. The suggestions below review those techniques as well as offer other tools for troubleshooting a network. Here is a review of previous and some additional techniques for troubleshooting a network. These techniques as stated before can be the best tools in curing network problems. The first and most important thing is to use your engineering journal and take notes. Note taking can define a clear path to diagnosing a problem. It can tell you what you have already tried and what effect it had on the problem. This can be extremely valuable to the troubleshooter so those previous attempts at resolving the problem won't be needlessly repeated as time goes on. Taking notes is also very valuable if the problem is handed off to another technician to prevent them from having to redo all of the work that was already done. A copy of these notes should be included with the resolution of the problem when the trouble ticket on this job is completed. This can provide a reference for any similar problems that might happen related to this particular problem. Another essential element of preemptive troubleshooting is labeling. Label everything, including both ends of a horizontal cable run. This label should include not only the number of the cable but also where the other end is located and the usage of the cable, for example, voice, data or video. This type of label can be even more valuable than a wiring cut sheet when it comes to troubleshooting, because it is located right where the unit is and not stuck in a drawer somewhere. Along with the wire labels, labeling each port on a hub, switch or router as to location, purpose, and point of connection will greatly improve the ease with which problems can be solved. Finally, all other components attached to the network should also be labeled as to their location and purpose. With this type of labeling, all components can be located and their purpose on the network easily defined. Proper labeling, used with the network documentation created when the network was built and updated, will give a complete picture of the network and its relationships. One other important reminder from the previous semester is that the documentation is only useful if it is current. All changes made to the network must be documented both on the devices or wire that is changed and the paper documentation used to define the complete network. The first step in network troubleshooting is the definition of the problem. This definition can be a consolidation of many different sources. One of the sources could be a trouble ticket or help desk report, which initially identifies a problem. Another might be a phone conversation with the user having the problem to gather more information about the problem. Network monitoring tools may provide a more complete idea about the specific problem to be resolved. Other users and your own observations will provide information. Evaluating all of this information may give the troubleshooter a much clearer starting place to resolve the problem, rather than by working from any one of the sources alone.