[Dovecot] Staged migration from mbox to maildir

[Sebastian Kayser]

* Stewart Dean <sdean at bard.edu> wrote:
> So much changes in this migration that the ideal way to do it would be 
> to begin with a few users or a department, then migrate the users 
> affinity group by affinity group: first an institute or so, then the 
> faculty, then the staff, then the students, moving to bigger and bigger 
> groupings as the bugs work out of the migration and the move becomes 
> more assured.
> 
> We use sendmail and procmail.  There's no problem there, as the 
> ~./procmailrc can be changed to over-ride the mbox default until all 
> groups are done and it become the default.
> The problem comes with IMAP.  While dovecot can tell if a folder is mbox 
> or maildir, it has to be pointed to the right place (by namespace 
> definitions in the client, IIRC), and the default of putting the inbox 
> under ~/mail is one I'd like to embrace for various reason...but given 
> that that means moved inbox folders and *that* means either making a 
> global change (there goes staged migration) OR changing the namespace 
> definitions on each PC.  I can get to the early few and change the 
> namespaces definition, but there doesn't appear to any equivalent 
> (enlighten me, if I'm missing something) to ~/.procmailrc for imap, so 
> that I don't have to get on the client machine.

I don't know whether i fully understand what you are trying to achieve,
but dovecot can work with a per user mail_location (passed via userdb)
[1] that might help in your situation. Furthermore you can get _very_
flexible in determining the mail location (or even doing a lot of other
things) by using a wrapper script to mail_executable [2].

Sebastian

[1] http://wiki.dovecot.org/MailLocation
[2] http://wiki.dovecot.org/PostLoginScripting