Additionally we use strato as our primary mail-service in the open wild and have the OX connected to it. So far so good. The only problem is, strato doesn’t support the sieve protocol for external services, so we are not able to use mailfilters (think: autoresponder when you are on holiday).
So, my idea is, to set up an own mailserver, which fetches from strato through imap, serves imap locally via dovecot and uses dovecot-sieve, to enable sieve rules in OX. It could look like this:
I am going to write an update as soon as I’ve figured out, how that all sticks together, especially how I am going to handle the synchronisation and user setup (think: we have 100+ employees)