I currently have 5 ISPConfig3 servers setup under the multi server configuration. I have to change the IP addresses of all 5 servers. How do I do this so that ISPConfig3 knows where to find the new servers and syncronize correctly. I am using Ubuntu 16.04 and changing the IP addresses in the OS is not an issue. Update the /etc/network/interfaces, /etc/hosts and reboot. But that will break synchronization for ISPConfig3 I believe due to the multi server setup.