The troubleshooting process consists of several phases, each responsible for performing different actions. The movement through the phases defines the troubleshooting method, and although all methods will eventually solve the problem in the end, not all of them are equally efficient in all situations.
The image above shows the movement through the phases and the troubleshooting process is as follows:
Define the problem: The first step in troubleshooting is defining the problem. This happens when a user reports that something is not working properly, such as being unable to access an internal server, open web pages, or anything else.
Gather information: After the problem is defined, the diagnostics process starts, and most of the troubleshooting time is spent in this phase. First, you need to gather as much information as possible about the problem. Such information would be when the problem occurred, whether the user did something that might have caused that problem, etc.
Analyze the information: Next, all that information is analyzed to better understand the problem and what might have caused it. The time you spend on this phase depends on the amount of gathered information, and you might come up with several potential causes for the reported problem.
Eliminate potential causes: In this phase, you need to eliminate all potential causes to focus only on the real ones during the rest of the troubleshooting process. However, if you misjudge and eliminate the real cause, you will continue troubleshooting the causes that have not produced the reported problem.
As a result, you will spend a lot of time troubleshooting based on incorrect information, which will not provide any positive feedback. In the end, you will have to go back to the beginning of the troubleshooting process, repeat the same steps, and hopefully not eliminate the real cause again.
Propose a hypothesis: Once all potential causes are eliminated except for the real one, you need to propose a hypothesis that should solve the problem.
Test hypothesis: To verify the hypothesis, you need to test it, and the only way to do it is to apply the solution in practice.
Solving the problem and documenting it: If the hypothesis solves the problem, you need to document it so you or other administrators will have guidance on approaching the same or similar problem in the future without going through the whole process again. However, if the hypothesis is wrong, you have to test another hypothesis.
Note: The time one troubleshooter spends on each phase and how they move from phase to phase can significantly differ from person to person. This is what separates rookies from expert troubleshooters.