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To mention my work detailly, on GNS3, I have one c7200 cisco router as NAS(for administration access to router only, not to provide an internet connection) and a freeradius server on ubuntu server 14.04. I configured my NAS to send accounting update per one minute. In /var/log/freeradius/radacct/(ip of the nas)/detail-(date), I can read a txt file where some accounting infos are written but when I issue "radwho" command, I can not see anything but the titles for non-written accounting details.

Read the debug output, and look for the “radutmp” module.  What does it say when the server receives an  Accounting-Request?

Unfortunately I saw no output by radutmp module. I only saw auth_log outputs that prompting outputs into a txt file (I tried some configurations on detail.log). I think that I may have not noticed a useful information but I have no idea about what it is. However, because I configured my NAS to request accounting logouts, my server send accounting reply when any user log off on the NAS.

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I also issued freeradius -X command and got "ready to process request", my server can properly process authentication requests also.

The point is to read the output *after* it says “Ready to process requests”.  That tells you what it’s doing when it processes

requests.

I read each row after receiving a request. I couldn't see any radutmp module output as I said above. At least I know what I need to focus on now.

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However, I'm not completely unsuccessful to get any output from radwho. I had done some configurations on freeradius and managed to get proper outputs with radwho on the same topology and system. Unfortunately, my server got disfunctioned when I had tried to configure it for active directory authentication. I could only recovered it by re-installing then I lost and forgot what I did to use radwho.

You should use “git” for revision control on the raddb directory.  It helps a lot.

I should have learned this function before. Due to malfunctions on my computer, I lost whole topology and virtual machines but I will remember this advice in future thank you a lot.

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I can't remember what I did to get radwho output before I lost whole configuration and what I can't notice now.

If you send Accounting packets which have useful session data in them, radwho will “just work”.  

After reading this, I read my accounting configuration on the NAS. I suspected of a forgotten accounting command. Then I issued some accounting commands to apply "trial&error". Unfortunately, radwho didn't work again. I will continue to search for any missing accounting commands. In general, those details were all caused from the previous topology which I lost completely recently. I will build it up again in a few days. After a short process of adding clients and users, I will read debug details as you recommend and share results. Thanks for your help. -- Mert Uzun Elektrik Mühendisliği Bölümü-2. Sınıf Öğrencisi