Technical Tip: The Forticlient on Smartphone getting an error messages 'Opening multiple connections are not permitted'

[duenlim]

Description	This article describes the reason why FortiGate responds to the message 'Opening multiple connections are not permitted' to EMS and FortiClient Android when the 'Limit Users to One SSL VPN Connection at a Time' is enabled on FortiGate and the 'auto-connect' function in FortiClient.
Scope	FortiGate v7.0/v7.2.
Solution	Upon connecting to SSL VPN get prompted with 'Already Logged In' as shown in the picture. Select 'PROCEED' it will continue to connect to SSL VPN and disconnect previous connections. The Smartphone 1st got an IP 203.203.203.203 from the mobile network and connected to SSL VPN. After turning on and off Airplane mode within five minutes (FortiClient auto-connect) it gets error messages as shown above. That is because Smartphones get a difference IP 203.203.203.230 from mobile networks. This can be verified by periodically running the CLI commands : get vpn ssl monitor diagnose vpn ssl list Note: There will be no issue as long as the Smartphone gets the same IP address whenever turns on and off Airplane mode.