I have been loosely following discussions dsync replication, but I am wondering if this tool still in a testing phase or has it been committed as a production part of Dovecot? I would like to do some testing with the protocol to see if it's capable of handling the change rate our mail service generates, which has about 23,000 active users. We are trying to find solutions for a two site setup where mail processing is either being done at the primary data center A and fails over to a hot standby cluster at the secondary data center B, or where both data centers are doing active processing. I have been unable to find documentation on dsync replication on the wiki, so if there is any documentation available on how to setup dsync replication I would appreciate a nudge in the right direction.