On 02/10/2011 12:04 AM, Timo Sirainen wrote:

On Wed, 2011-02-09 at 07:12 +0100, Frank Bonnet wrote:

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We actually use MBOX format on our mailhub but this does not permit to create IMAP subfolders. It does, although it's less obvious how to do that with most clients.

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My problem is to choose the format that will permit imap subfolders creation. Even mbox supports it, although the filesystem becomes a bit ugly: http://wiki2.dovecot.org/MboxChildFolders

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Maildir is not my favorite format and I wonder about MDBOX.

Does it permit imap subfolders creation ? Sure.

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It is possible to convert from MBOX to MDBOX in one shot ? You can run dsync one user at a time, and of course you can run it for as many users as you want. I'd suggest switching a few users first to make sure everything will work nicely.

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Is it stable / mature enoug for a production server ( 4000 users ) ? I hope so. :)

Hello

dsync has worked well in converting all my imap folders which are accessibles from Tbird

but it does not convert my INBOX ... which seems empty

the command was

dsync -u bonnetf mirror mbox:/user/bonnetf/mail:INBOX=/var/mail/bonnetf

What did I missed ?

On 09/02/2011 23:04, Timo Sirainen wrote:

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It is possible to convert from MBOX to MDBOX in one shot ? You can run dsync one user at a time, and of course you can run it for as many users as you want. I'd suggest switching a few users first to make sure everything will work nicely.

Just to highlight the marvellous "Proxy" feature in Dovecot...

If you are migrating users then you can set your main dovecot instance to proxy to a test instance based on various criteria. In this way it's possible to do a near live migration one user at a time without changing any user visible server options. This feature is also great for moving machines between IPs or other similar changes

I'm sure all the big installations already thought about this, but it's just something that the "smaller" installations might not have given some thought to. I fall into the "smaller" category, but very early on I put a field in our user db showing which server the user lives on.
Now with a small extra addition to the transport routing, postfix automatically delivers to the correct final server (no matter which server mail is injected into) and dovecot also proxies to the correct destination server (again no matter which you initially connect to).
This is extremely helpful when you move stuff around!!

Good luck - very interested to hear how performance of mdbox works out?

Ed W