Diagnosing Problems · Topic 1 of 6
Troubleshooting Methods and Help Desk Practice
Learn a step by step troubleshooting method, how help desk ticketing and documentation work, and how to gather information and prioritise problems.
- 4 min
- Troubleshooting follows steps: identify, theory, test, act, verify, document.
- Gather information before changing anything, and find out what changed.
- Top down, bottom up and divide and conquer are three ways to approach a problem.
What it is
Troubleshooting is a structured way of finding and fixing the cause of a problem.
A good technician does not guess. They follow steps, collect facts, test one idea at a time, and write down what they find.
The help desk is the first point of contact for users with problems. It records each problem in a ticket, and works through the ticket until it is solved.
How it works
A method keeps the work calm and repeatable, and good records mean the next person does not start from scratch.
A troubleshooting method
A common method has six steps.
- Identify the problem. Ask questions, gather information and find out what changed.
- Establish a theory of the probable cause. Start with the simplest and most likely.
- Test the theory. If it is wrong, form a new one. If you cannot confirm it, ask for help.
- Plan and act. Make a plan to fix the problem and carry it out.
- Verify. Check that the whole system works and that users are happy. Add steps to stop it recurring.
- Document what you found, what you did and the result.
Ways to approach the network
You can also decide where to look first.
| Approach | How it works |
|---|---|
| Top down | Start at the application layer and work down |
| Bottom up | Start at the physical layer, such as cables and lights, and work up |
| Divide and conquer | Start in the middle, such as with a ping, and move up or down from there |
Bottom up suits a case where nothing works at all. Top down suits a case where one program fails.
Information gathering
Collect the facts before you change anything. Useful questions are:
- What exactly is wrong, and what error is shown?
- When did it start, and did anything change before then?
- Who is affected, one user or many?
- Has it worked before, and is it still happening?
Look at the device itself. Check lights, cables, IP settings and the results of simple tests. Try to reproduce the problem.
Ticketing and prioritisation
A ticket normally holds the user's details, a description, the date and time, a priority, the status and the person it is assigned to. It also holds a record of every action and a closing note.
Not every problem can be fixed at once, so tickets are given a priority. Priority depends on how many people are affected, how serious the effect is, and how urgent the need is. A fault that stops a whole office comes before a slow printer for one user.
Help desks are often arranged in levels. Level 1 handles simple and common problems. Escalation passes a ticket to a more specialised team when it needs more skill or access.
Documentation, policies and procedures
Organisations have policies, which say what is allowed, and procedures, which give the steps to follow. A technician follows them, for example when resetting a password or handling a security problem.
Good documentation is accurate and complete. It states what the problem was, the steps tried, the fix, and any changes to the network. It also helps spot repeated faults and trains new staff.
What to remember for the exam
Seven facts cover most questions on this topic.
- Troubleshooting follows steps: identify, theory, test, act, verify, document.
- Gather information before changing anything, and find out what changed.
- Top down, bottom up and divide and conquer are three ways to approach a problem.
- A ticket records the problem, the actions and the result.
- Priority depends on the number of users affected and the seriousness of the effect.
- Escalate a ticket when it needs more skill or access.
- Accurate and complete documentation is part of the job.
Change one thing at a time. If you change several, you cannot tell which one fixed the problem.
Common mistakes
These four errors appear again and again.
Guessing and changing settings at once. Gather the facts and test one theory at a time.
Skipping the documentation. The next technician repeats the work if the notes are missing.
Setting priority by who shouts loudest. Use the number of people affected and the seriousness.
Closing a ticket before checking with the user. Verify that the fix works first.
Follow the organisation's policies, such as security rules, even when a shortcut seems faster.
Check yourself
Work through these three questions.
What should you do before changing any settings?
Gather information, such as what is wrong, when it started and what changed.
Which problem should get the higher priority, one printer or a whole office with no network?
The whole office, because more users are affected and the effect is more serious.
Why is documentation part of troubleshooting?
It records what was found and done, so others can learn from it and avoid repeating the work.
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