Dovecot mail_location

Thanks, but a bit tricky as my email system is down while I work it all out.

As per my other post, I upgraded the server from Leopard to Snow L. Email doesn't work, seems that Mail and Dovecot are not playing well with my (legacy) settings that worked ok for Cyrus. So I'm looking into manipulating the mail storage at both tends to try and effect a cure. In the meantime, I'd like to use LAYOUT-fs so Dovecot will store messages in a folder hierarchy instead of the default single flat level. Ok, I can do that by adding it to dovecot.conf, but Server Admin controls dovecot.conf and if I add :LAYOUT=fs to the end of the mail_location string, it then adds /%u onto the end in dovecot.conf, but which is hidden by Server Admin. In any case, this is of course wrong as :LAYOUT=fs has to follow the path.

Then I could not actually remember seeing %u at the end of the original mail_location string in dovecot.conf. was it there all along?

I then became puzzled by the fact that %u represents the username, but the actual user's folders within the main path specified in mail_location did not have the name of the user. Instead their name is the GUID of the user (owned by that user so you can still see whose folder it is) and this is as described in Apple's server docs for 10.6 Mail Service.

So on the one hand we have the location being specified with the username, but the folders get created as the GUID and I just don't see how or why. Is there another setting somewhere that states %u should be the GUID and not the name? If so, I haven't found it.

It also leaves me with the problem that you CANNOT customise the mail_location setting in dovecot.conf, because Server Admin just stupidly rewrites it and gets it wrong. But why is Apple's dovecot using GUID and not the username?

The problem was that the IMAP prefix was originally set to "~". This was from when I was using a linux server and wanted mail stored in the home folder. Cyrus however seems to deal with the "~" differently, but was happy to work with it as just a regular character, so mail was no longer in the user's home folder, which now suited me better so I didn't look into it any further.

However, upgrading to Snow Leopard Server and Dovecot meant that all the mail folders were stored by Dovecot as ".~.whatever.thefolder.nameis", including e.g. ".~.Drafts". On first starting Mail on the client after the upgrade, the mail all appeared to be there, but there was obviously a problem and I concluded was that although Cyrus could deal with the "~", Dovecot could not.

So, I moved all the local mail up one level out of the "~" folder and threw that folder away. Then I renamed all the Dovecot mail folders to remove the ".~" at the beginning. Reset the client's Mail IMAP path to empty and started the Mail Service on the server. After some activity all the mail is there and accessible, so it basically worked and I'm no longer stuck with that spurious "~" IMAP path prefix. However, many messages are now showing as unread, although not all which is bizarre, but relatively easy to fix, if a bit tedious.

So all I'm left with now is the %u - GUID puzzle.

I understand what the GUID is and that they might want to use that instead of the username, but what I cannot understand is that the dovecot.conf file explicitly states mail_location as /var/spool/imap/dovecot/mail/%u, but the actual folders it creates and uses are /var/spool/imap/dovecot/mail/GUID. So what is telling it to do something different from its own conf file? Where is the configuration parameter that says "use GUID and NOT the username"? That's what I don't get.

See, even this forum cannot handle the tilde character normally. I was trying to explain about the '.~' prefix, but using double quotes throws out the formatting. It's better with single quotes.

Indeed, unless you're using LAYOUT=fs, but it seems to be impossible in Apple's implementation. But that's not the problem.

What I am still trying to understand is that the dovecot.conf file specifies using %u (which is the username according to all the docs I've found), but the folders get created named as the GUID. So where is the configuration that says use GUID and NOT the username?