GUI CLI - "Connection lost. Press Enter to start a new session"

Just a couple of ideas:

- when you start a new session, do you also change the port to the new 4433 in the browser?

https://fortigateIP:4433

- did you check if port 4433 is not mapped to an internal host (a VIP), or maybe SSLVPN (show full | grep 4433 -f)

I have the same problem. When I access the Web for the HA IP of FortiGate and then click the CLI icon, I get this message. When I access the management IP for any one of them, it works well. The HA and management IP addresses are in same subnet.

The problem with the HA FortiGate that does not has a management IP on the interface.

I found the solution.

https://community.fortinet.com/t5/FortiGate/Technical-Tip-Fix-CLI-console-from-FortiGate-GUI/ta-p/226238

I did check and found the SSL port is already changed. The solution worked. But I don't know the port 443 is used by what..

Use Chrome