[Dovecot] Maildir configuration vs ZFS and snapshots...

[Mike Brudenell]

Greetings -

I'm intrigued by your suggestion of providing read-only access to  
mail folders in the snapshots...

On 3 Jul 2007, at 15:20, Peter Eriksson wrote:

> Now,I can access the normal Maildir INBOX and folders nicely via
> Dovecot/IMAP. The thing is I'd like to be able to access the
> snapshot too via Dovecot/IMAP somehow. My first idea was to use
> Dovecots namespace feature like this in the config file:
>
> 	namespace private {
> 	  separator = /
> 		  prefix = snapshot/
> 		  location = maildir:~/.zfs/snapshot/2007-06-18/ 
> Maildir:CONTROL=~/.dovecot/control:INDEX=~/.dovecot/index
> 	}
>
> This works great for the mail folders inside the Maildir - but not  
> for the INBOX which isn't displayed at all... (Ie, under the  
> "snapshot" prefix I only see "Trash" etc when looking at the folder  
> from an IMAP client).

We are switching from the UW IMAP server with local disks to Dovecot  
using a NetApp filer.  The filer provides snapshots too, although  
with a slightly different layout as the ".snapshot" directory appears  
in each and every directory with its files and folders.  For example:

     ~/Maildir/.snapshot/nightly.0/...
     ~/Maildir/.snapshot/nightly.1/...
     ~/Maildir/.snapshot/nightly.2/...
         etc

where the ".0" suffixed directory is the most recent etc.

In your example your snapshots seem to be in directories named after  
a specific date (when the snapshot was taken?).  I was wondering if  
you had some clever way of providing access to these; in your example  
above you hard-code the names into the Dovecot configuration file,  
which doesn't seem practical for a live system?

Basically I'm trying to mimic your setup and was wondering if you had  
already solved the problem of getting down from your "snapshot"  
directory through the intermediate level to the Maildir itself.

In passing, would I need to use a separate CONTROL and INDEX storage  
area for these, or will the files for the snapshot folders live  
happily alongside those for the live area?  (I'm not too sure how the  
organisation of these storage areas works when namespaces and  
prefixes are concerned!)

Cheers,
Mike B-)

-- 
The Computing Service, University of York, Heslington, York Yo10 5DD, UK
Tel:+44-1904-433811  FAX:+44-1904-433740

* Unsolicited commercial e-mail is NOT welcome at this e-mail address. *