I have the same problem of you andre.amaro i see theses logs in my fortiGate/Logs/Wifi Events.
You or another one did find the resolution ?
With the support i hide theses logs on my fortiGate to avoid so many entries in my fortianalyzer. But still i think i have problems with my clients in wifi and i think theses logs are the problem.
i believe that it is because for some reason for the WiFi the FortiGate logs the failed DNS requests, it doesn't do this on the LAN side.
looking at your screenshot the main cause is that NTS2000.nts2000.lan host. do your WiFi clients have an internal DNS server configured which should resolve this hostname? or do they have an external one which can't understand this hostname?
Yes all my clients can resolve the domain "nts2000.lan".
But on the example I don't have a machine called "nts2000".nts2000.lan. And this is the case for all other entries in my logs :
None of those above match a device in my group.
Yes all my DNS servers support each device on my LAN. These servers are synchronized between them every 15 minutes.
But in the logs it's indicatated that it's the DNS server which answers domain is non-existent :
Server X.X.X.X replied "non-existing domain".[/ul]
Or then this is the FortiGate / FortiAP misidentifies the devices and sends incorrect data to the DNS server. Maybe that explains the weird name resolutions above.
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