Hi Patrick, You can use the proxy in combination with a database to return a fixed backend host per user, but be aware of the fact that if one host goes down, all mailboxes on this host will also be down (if there is no replica).
The director uses a hash function instead and can only be used when all backend nodes can serve the same set of users. The director uses the proxy feature to forward the connection to the backend host, but the backend is selected by the hash function depending on the username. In short: use the proxy not the director, but keep copies/replica of your mailboxes somewhere in case one host goes down. Regards Daniel
