dovecot - Mar 2009 - Staged migration from mbox to maildir

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.

Is this correct or am I (hopefully) wrong and there *is* a way to change 
things on the server that allows for staged migration?  Oh, I would so 
like to be wrong!
IMAP should have an rc file.............
-- 
"Eppur si muove." (But Still it moves) Galileo, leaving the
Inquisition,
after buckling under the threat of torture and excommunication and 
recanting from his proof that the heavens do not revolve around the 
earth --
Stewart Dean, Unix System Admin, Henderson Computer Center, Bard 
College, Annandale, New York 12504 sdean at bard.edu voice: 845-758-7475, 
fax: 845-758-7035

Hi,

I'm working with a an IMAP client for a S60 (Nokia) phone and we are having
a
small problem (not in Dovecot!) but somewhere deep in our own system which has 
to do with certificates that are self signed.

Somehow in some circumstance if you accept a self-signed certificate as an
exception then the client will send a strange command to the imap-login which 
it doesn't recognize. We are quite sure this is a problem in our own system 
and not with Dovecot

Since we have no access to the certificate (SSL/TLS) handling code we are a 
bit at loss here and have to "proof" to "the other" guys in
Finland that it's
there fault :-)

The type of errors that show up in Dovecot in these circumstances are (with 
the real username and IP address removed)

------------
imap-login: Disconnected (no auth attempts): rip=some.ip.address 
user_name=192.168.0.2, TLS handshaking: SSL_accept() failed: 
error:140943F2:SSL routines:SSL3_READ_BYTES:sslv3 alert unexpectedmessage
------------

Is there some more debugging we could enable to see exactly the type of wrong 
command the SSL/certificate handling are send in the handshake procedure ?

(We have all the debug and/or the auth_* flags in dovecot.conf enabled 
already)

Any idea?

Johan

Words by Stewart Dean [Wed, Mar 18, 2009 at 02:10:53PM
-0400]:
> 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.
>
Tell me about it, we have to plan the migration of 6 million accounts
(many tens of TB) from Maildir to dbox in the near time :)

-- 
Jose Celestino | http://japc.uncovering.org/files/japc-pgpkey.asc
----------------------------------------------------------------
"One man?s theology is another man?s belly laugh." -- Robert A.
Heinlein

* 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

On Mar 18, 2009, at 2:10 PM, Stewart Dean wrote:
> 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.
By namespace definitions you probably mean the IMAP clients' "imap  
folder prefix" or whatever they happen to call them in different  
clients? You can create namespaces for backwards compatibility, you  
probably want similar namespaces to what is described here under UW- 
IMAP examples: http://wiki.dovecot.org/Namespaces

You could do that kind of a change already with mbox users to make  
sure everything works. Then have your users use one of the two  
mail_locations (by returning "mail" extra field from userdb):

  * mail_location = mbox:~/mail
  * mail_location = maildir:~/Maildir