Joseph Tam
On Tue, 5 Jul 2011, list <at> airstreamcomm.net wrote:
I didn't do anything special other than to use
pop3_reuse_xuidl = yes
so that clients don't re-download all their messages.
Did you convert the mbox emails to maildir format as well, or just put dovecot in front of the mbox files and run with the config setting you described above?
No, I left the mailboxes as mbox and did not convert to maildir. I had all sorts of mail clients and some use direct file access to their mailbox, so it requires a lot more deep-think before I can contemplate moving to maildir.
Many people on this list have successfuly migrated to maildir so I don't think you'll have too much trouble.
You'll appreciate that dovecot avoids some of the problems I had with qpopper:
- qpopper made temp copies of a user's INBOX, and if you didn't put the drop copy on another filesytem, you essentially halved a user's quota.
- because of the above, qpopper eats I/O like candy.
- multiple client qoppper access will trouncing/locking user INBOXs.
Joseph Tam
We recently completed the migration in our company from qpopper/mbox to dovecot/mbox using only pop3_reuse_xuidl = yes and while everything went much easier than we feared we came across an interesting problem that you might want to pay attention to.
We use dovecot to provide both pop3 and imap (directly and via webmail) access to our client's mailboxes and we noticed that when a client moves a mail to a different folder and then back into INBOX (say he deleted it by mistake and moves it back), dovecot inserts the same X-UIDL into it's cache, thus creating duplicate entries.
When a pop3 client sees this (at least outlook in our case) it think's that there's something wrong with the server's X-UIDL handling and re-downloads the duplicate messages. EVERY time the user checks his mails.
We're still in the middle of troubleshooting this, but I believe deleting dovecot's cache would solve the problem for a particular mailbox, but I can't think of anything that would solve it permenately.
Dimos Alevizos