> On 22 Sep 2017, at 00:15, Adi Pircalabu <a...@ddns.com.au> wrote: > > Using rsync should be fine, I've done it myself recently several times. What > you need to consider: > 1. The downtime required during the final incremental transfer. > 2. If you're using the same uid/gid on the destination server make sure you > preserve them when transferring the data across. > 3. To avoid duplicate messages in the destination you *must* use --delete > rsync switch for the incremental transfers. > > Important: I'm assuming you're using virtual mailboxes under the same uid/gid. > > Suggested mandatory steps, ymmv: > 1. Configure Dovecot in the destination to use Maildir and test everything: > logging, SSL, authentication, mail delivery and so on. If you have > Courier-IMAP specific configuration, e.g. folders that are being > automatically created/subscribed upon the first login, replicate it and test > it on the Dovecot server as well. > 2. Do the initial data transfer using "-avz --numeric-ids" and see if you're > happy with the result in the destination. > 3. Run several incrementals adding "--delete" switch, followed by > courier-dovecot-migrate.pl *executed as the mail user* to get a ballpark > figure for the estimated outage window. > 4. Test few mailboxes post-migration and compare the results with the source > server. > 5. On Day D, stop Courier-IMAP and Dovecot services on both servers to > prevent any mailbox changes and run the last incremental, sanity checks, IP > reconfiguration if Dovecot is the drop-in replacement, start Dovecot, another > round of sanity checks, check the logs and so on. Here you're already at the > point of no return :)
This is all more or less as I hoped or planned it, although you have mentioned some details that I will now be sure not to overlook. Many thanks. Stroller.
