That amount of clashes is nothing to worry about I'd say. On the LB-vdom I mentioned earlier the log shows 6-digit amounts of clashes. The clash counter is reset at reboot btw, and is not related to the current amount of sessions. It is just an ongoing counter.
To my knowledge, all restarts of applications with restart option 11 (segmentation fault) in FortiOS is seen as a crash. It doesn't have to mean anything bad per se. The OS recycles processes all the time using option 15 (graceful restart). When that doesn't work, it moves on to try to restart with option 11 wich will generate a log entry in the syslog. The recycle process continues all the time, buffers needs to be cleared etc etc. However, a constant restarting of the same application can also mean various problems - Memory leaks, buffer overflows etc.
I checked your log, but I can't see anything else then the PID and some weird ASCII-signs as application name. It does look kinda odd.
Check your logs and keep track of if the application crash log entries correlates with odd behaviour in the firewall, we're talking sudden reboots, functions and features stopping/not working.
What does "diagnose debug crashlog read" say?
Also, do a "diagnose sys top", a few times during the day. Do you have processes in Z or D state?
I agree with bartman10: Fortinet may not ship the Wifi-models with a massive bug like this. I got an interim-build now - there the bug's fixed - but this build should be public as soon as it is fixed ... the support didn't help this guy 'till now - that's not okay ... although there IS a working build they didn't even offer him ...
Going with 5.4.0 seems to me like playing lottery ... at the moment ...
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