One of the techniques that is used the least is baselining the network. Yet, it is one of the most useful techniques. Baselining is recording data based on the "normal" performance of the network. By knowing how the network performs when users are satisfied, you have a point of comparison when problems are reported. Have the level of broadcasts gone up? Are there new protocols on the network? Is utilization higher? Is the ERP application response time slower? Questions like these are impossible to answer without the corresponding data gathered under normal operating circumstances. This information is rarely provided by network equipment manufacturers. So, network managers need to find time in their schedules to record it when they aren't under pressure.
Selecting the right tools can be more challenging than it appears. The more theoretically oriented engineer often wants a protocol analyzer as their only tool. While it allows them to do a deep analysis of the network in some circumstances, finding a failing fiber optic cable or a network interface card that is out of specification, may be nearly impossible. Yet, the engineer that wants to avoid theory altogether might simply swap out components until the problem disappears. This can take too much time and lead to many discarded, expensive but perfectly functional network components. Here are some points that may be helpful as you approach a troubleshooting problem:
- Analyze the network as a whole.
- Follow a logical sequence of steps.
- Zero-in on the root source of the problem and make one adjustment or change one part to eliminate the problem.
- Don't focus on completely understanding the problem until after the network is functioning properly.
- Provide feedback and training to the user. It's good diplomacy and may eliminate user generated problems in the future.