This is something I noticed while giving a remote demonstration of a system to a customer. I added their public IP address to our firewall to let it through, then also added it to the Gateway: Allowed Addresses field in System Properties in the Gateway Configurator.
This worked fine and they could launch the system. When I finished the demo I removed their IP address from the Allowed Addresses field and restarted the FactoryPMI server using the Restart button at the top of the Configurator page. I noticed continual activity on the web link - when I checked with Wireshark, their client (still running) was still asking for and being sent data. I then shut down FactorySQL, FactoryPMI and MySQL. The client was still asking for data but not getting a reply. When I restarted the software, it immediately started sending data back to the client! The only was I could stop it was to block the address in our firewall.
Can you confirm this behaviour? I thought restarting FactoryPMI would immediately block a removed address.