I need some advice. I have a ISPconfig email server (with remote API user) that automatically creates a new user after a 3rd party site (www.mail.fish) makes the purchase and sends the confirmation of email account creation with password. I want to start expanding that email server for redundancy and security but mostly to support different "family name email domains". Now all the family name domains and users are in one server. By delivering mail to different IP's I can "spread" the load to different servers. I wan't to start migrating @mattila.eu domain to it's own LXC container and @lee.ski domain to it's own LXC container while keeping all the user account management in the "Master" API node. In effect I wan't to minimize disruptions on the Primary node while providing redundancy with the help of the slave nodes. Master ISPconfig server with remote API -domain1.eu slave server -domain2.eu slave server etc. I have examined many different strategies like syncing the vmail folder with different 3rd party tools but I would like to stick with ISPconfig as much as possible to keep future compatibility. What do you think? What would be the best way to go about this?