Wireless Troubleshooting

What this chapter covers

This chapter teaches you how to find and fix wireless problems in a structured way.

It covers the method for working out why a client cannot connect, the numbers that describe link quality, and the RouterOS tools that show the air and the link. Together they let you move from a vague complaint to a specific cause.

The pages use the legacy wireless menus for most commands and note where the wifi driver differs.

How the topics fit together

The three topics are three steps of one investigation.

The first page gives you the method and the registration table, which tells you whether the client reached the access point at all. The second page explains the metrics that tell you how good the link is. The third page covers the tools that confirm the cause, such as scan, snooper, sniffer and the bandwidth test.

• Client troubleshooting and the registration table shows how to sort a symptom and use the table and the log.
• Signal quality metrics explains signal, noise floor, SNR, CCQ and data rates.
• Diagnostic tools explains what each wireless tool shows and when to use it.

How to use these pages

Each topic page has the same shape, so you can skim for what you need.

• What it is: the idea in plain words.
• How it works: the mechanism, with diagrams and example commands.
• What to remember for the exam: the facts to memorise.
• Common mistakes: the classic traps.
• Check yourself: three questions to test your understanding.

Read the pages in order, because the method on the first page uses the numbers on the second page and the tools on the third.

Practise the SNR calculation until it is automatic. Then pick a symptom, such as a client that joins but is slow, and say aloud which numbers and tools you would check and in which order.