On Thu, 2009-11-12 at 16:04 -0800, Jordan Tardif wrote:
Heres a litle bit of background on what we are doing and maybe if you have time you can let me know what you think the best way of doing this would be. When we move users to dovecot servers, we first create a new user on the destination machine, then do a rsync from the old user (that contains all the courier* files) to the new one, and then run the migration script found in the dovecot wiki to convert the courier* files to dovecot*. 6 Hours later we rsync from the old user to the new one again to make sure that any emails that have been delived to the old user while dns updates make it to the new users account. Then we run the migration script again with --overwrite so it creates the new courier* files. Would you also reccomend removing any dovecot.index.cache files at this time as well? Can you think of another way to do this move so that dovecot would not have this problem with duplicates?
When do the imap/pop3 sessions actually start using the new machine? Does that depend on DNS also? Running migration script multiple times isn't a good idea. It can change IMAP UIDs and cause trouble with clients that use a local cache. It could even lose messages since client doesn't realize that there's a new message with an existing one's UID..
Yes that depends on DNS updating. So is there not way to avoid this Duplication problem if you need to do an rsync 2x?
-- Jordan Tardif DreamHost