Sami is correct. imapsync loses data. Source -> imapsync -> destination : the mailboxes are different to an IMAP client Source -> dsync -> destination (running Dovecot w/doveadm): the mailboxes are the same
You may not care that your users w/100,000 message mailboxes that have been cached on their client now have to invalidate that entire cache (and most likely re-download all of those messages). So there is zero argument that, due to IMAP metadata loss, this is something that doesn't happen if dsync (or rsync) is used. michael > On September 4, 2018 at 9:45 AM Rick Romero <r...@havokmon.com> wrote: > > > Quoting Robert Schetterer <r...@sys4.de mailto:r...@sys4.de >: > > > > > > Am 04.09.2018 um 17:18 schrieb Sami Ketola: > > > > > > > > > > > > > > > > > > On 4 Sep 2018, at 18.00, Robert Schetterer > > > > <r...@sys4.de mailto:r...@sys4.de > wrote: > > > > > > > > Am 04.09.2018 um 16:52 schrieb Sami Ketola: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > On 4 Sep 2018, at 17.47, Robert Schetterer > > > > > > <r...@sys4.de mailto:r...@sys4.de > wrote: > > > > > > > > > > > > Am 04.09.2018 um 09:41 schrieb Sami Ketola: > > > > > > > > > > > > > > > > > > > > > > > > > > imapsync always loses data > > > > > > > > > > > > > > > > > > > > never saw this, be carefull > > > > > > > by anounce such myths > > > > > > > > > > > > > > > > > It is a fact. Imapsync works over > > > > > > IMAP only and IMAP protocol does not even support transferring all > > > > > > data. At most at least UID numbering will be lost and end users > > > > > > need to invalidate their local caches. > > > > > > > > > > > > > > but using "looses data" might others think it > > > > > also may fail with imap, > > > > so be more detailed next time > > > > > > > > > > > UID number is also data that is saved on the IMAP > > > > backend. If that is lost then it's "lost data". > > > > > > Sami > > > > > > > > Sorry i migrated terrabytes of mail with imapsync and never > > > had a > > problem, it works as designed, also with maildir rsync did a good > > job, > > what never worked as it should was dsync ,cause of bugs ,that may > > changed now > > > > so this is my answer to topic > > > > "Best way to move mail from one server to another" > > > > > > > > https://imapsync.lamiral.info/FAQ.d/FAQ.Duplicates.txt > > Seems to use UIDs so that 'data' isn't lost. > >
