[Dovecot] Change to Maildir format (Was:Corrupted Mail?)

[Patrick De Zordo]

> -----Ursprüngliche Nachricht-----
> Von: dovecot [mailto:dovecot-bounces at dovecot.org] Im Auftrag von Arthur
> Dent
> Gesendet: Mittwoch, 28. Mai 2014 11:43
> An: dovecot at dovecot.org
> Betreff: [Dovecot] Change to Maildir format (Was:Corrupted Mail?)
> 
> I am seriously considering the change to Maildir format. I am however more
> than a little concerned that this could all go horribly wrong. This is what I am
> planning. Does it look sane?
> 
> Checklist
> 
> 1) Stop the mail queue (essentially stop fetchmail)
> 2) Stop Dovecot
> 3) Backup all mbox files
> 4) Edit all procmail recipes (actually I will probably do this first - working with
> copies - because this will be time-consuming) See below.
> 5) Convert mbox files to maildir using either mb2md or dsync (to be
> decided)
> 6) Change Dovecot config
> 	Actually - As far as I can tell no configuration change is required.
> Dovecot should just recognise the directories as maildirs. Is this right?
> 7) Restart Dovecot
> 8) Restart Fetchmail
> 

This would be nice, yes, BUT never ever go to script this and let it run without manual assisting!

Since you are doing this the first time,
I would prefer to test this steps a) on a different server or at least b) with a testaccount.

Then you have to test all scripts and other special settings with this mailbox, till you can be sure it all went well.
Then "one-by-one" could be migrated.. (again, just 2-3 users..)
Recheck again..


> Have I missed anything?
> 
> Procmail scripts:
> =================
> 
> I am quite concerned about this. I have a directory structure such as:
> 
> Home Inbox <-mbox
> Work Inbox <-mbox
> HobbyFile <-mbox
> Malware <-directory
>  L> Spam <-mbox
>  L> Virus <-mbox
> MLists <-directory
>  L> Fedora <-mbox
>  L> Dovecot <-mbox
>  L> Spamassassin <-mbox
>  L> ...etc...
> 
> My current procmail recipe for one example look like this:
> 	:0:
> 	* ^List-Id:.*users.lists.fedoraproject.org
> 	$DESTDIR/MLists/Fedora
> 
> I'm guessing it would need to change to:
> 	:0
> 	* ^List-Id:.*users.lists.fedoraproject.org
> 	$DESTDIR/.MLists.Fedora/
> 
> Is that right???
> (Note: remove locking colon ":" and use of "." and trailing "/" in path)

I'm not using procmail, but it seems that procmail is pasting the messages directly in to the maildirectory; this is *VERY* bad,
since every message should (or better have to) be delivered by dovecot himself into the maildirectory. (for example for indexing purpose, caching, ..)
Something like:
---8<-----------------------------------------------------------------------
	:0 w
  	| /location/of/dovecot-lda -d $USER
---8<-----------------------------------------------------------------------


> 
> Please advise - I am rather nervous of making a rather big mess here!
> 
> Thanks
> 
> Mark