Sadly I didn't find a solution for this. It was only in my lab so I just sacked it off. I don't know if a newer version of the VM would help. I'm also not sure if it's worth banging the VMware one in to see if it's an "image thing" or a problem with my PC and its configuration.
If you get anywhere with it then please let me know.
Being most of these seemed to happen after daylight savings kicked in, check the times on both your host and the 40gate and confirm they are the same. The 40gate will kick you out after x minutes of inactivity and if daylight savings is on the 40gate and your system is an hour behind, hello kick out!
Hello, i've managed to solve the problem. I mean it solved itself
It may not be able to help you but, i restarted the fortigate via console but it doesn't solve the issue and then i leave it for a couple day i guess, and it went back to normal. I don't know what exactly why. But i was taking a guess that the device is penetrated by someone by bruteforce. It's because i put an ip public to the wan interface and expose the fortigate web administration portal which is running on port 80. And then before the restart, i modified the web portal to port other than 80.
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