C9800 - Radioactive tracing

 

What is it?

This is a specific debug or conditional debug enabled on the WLC for the wireless clients; very useful to use when you have to figure out a specific behavior of one session among thousands or for one feature against many. So, as you might already figure, the condition can be set for a feature or for an identity, were the identity could be a MAC address, IP address, an interface, a session ID, etc.

You might be wondering, we already have the debug client, why would I need another tool as the radioactive trace, well is quite simple, the radioactive trace is already set up to give you all the insight on the whole session process from a wireless client, the association, authentication, IP learn, etc.  And everything is done “behind the scenes” with you only having to set it up and not worrying about keeping the session open or login the output.

How to enable

Now that we know what it is and the benefits of it, what’s next is how to make it work. There are two ways to enable the trace:

CLI

So, the first and to my opinion the simpler one is with a few CLI commands.

• #Debug platform condition feature wireless mac xxxx.xxxx.xxxx
•  #Debug platform condition start

Or

• #Debug wireless mac xxxx.xxxx.xxxx

The difference between the two is that the second will activate automatically for 30 minutes and the first will keep running until is stopped with the command #debug platform condition stop.

Now to check that it is ready we can use the commands #show platform condition and #show debug.

Finally, how to read it. Here the way I normally do it and I recommend is to create a text file and then export it to my PC to read on a more friendly tool, to do so you can use the command #show logging profile wireless start last 6 minutes to-file bootflash:trace.txt. This will export a text file with the logs which you can download to your computer with a simple transfer, or a copy command and setting a TFTP server on your computer; if you are more daring and want to simply read the logs directly on the CLI you can always use a #more bootfash:trace.txt

You also can always mix it up and download the file you create it from the GUI, you only need to the File Manager under the Administration menu, and it is pretty intuitive from there, just select the bootflash: unit and look for your file, make a right click and download it.

 

GUI

The GUI can be a little slower but is far simpler and highly recommended for users that want to take advantage of the automated tools from it. The steps are actually pretty simple

• Open the GUI
• Go to Troubleshooting -> Radioactive Trace

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•  Once it loads click on Add

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•  Set the MAC address or IP address to be debug and apply it.

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•  Click on Start to enable the commands.

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• Once you capture the condition you wanted click Stop

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• Click Generate

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• Set the interval you want to capture.

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• Be patient!
• Once completed Download the Logs.

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You can also view the logs directly on the GUI clicking on the View Logs button, but I would suggest downloading the information to your computer for a faster analysis.

 

What do I do with this?

 

Well this information is fairly useful for the TAC so you want to make sure to upload it to your case or in case you want to interpret it I will be posting a how to read post soon for you guys!

 

Reference articule: Cisco employee, "Cisco Catalyst 9800 Series Wireless Controller Software Configuration Guide, Cisco IOS XE Gibraltar 16.10.x", from cisco.com,  January 8, 2019

 

Thanks for reading!

Dan Lopez