[Dovecot] LMTP revisited

[Glenn Leavell]

On Sat, Jun 17, 2006 at 02:14:27PM +0300, Timo Sirainen wrote:

> On Fri, 2006-06-16 at 21:26 -0400, Glenn Leavell wrote:
> > I'd like to put in a vote for LMTP, and I'm wondering if anyone else has a
> > need for it.  Specifically, I'd love an LMTP-enabled LDA that uses hard
> > links when when delivering the same message to multiple recipients (I'm
> > thinking Maildir files), as it would be a nice way to facilitate so-called
> > Single Instance Storage.
> 
> This doesn't require LMTP. It could be implemented just as well with the
> current Dovecot LDA.

I think I'm probably showing my ignorance here:  My understanding is that
Dovecot's LDA gets called once per recipient, so that it wouldn't know
whether any given message is a duplicate.  Or is the idea that Dovecot's
LDA would be able to easily detect duplicates based on its own index
information?  If that's the case, would you start to include inode data in
Dovecot's index/metadata in order to perform the Maildir linking?

The reason I was thinking along the lines of LMTP is that it inherently
accepts multiple recipients for a single message, and I wasn't thinking
about the possibility of Dovecot's LDA being able to pick up on them in
some other way.

> The one thing that disturbs me with this kind of hardlinking is that
> then there are no Delivered-To headers (and others?) which are normally
> added to mails.

Yes, I guess we'd have to take that into account when deciding whether to
use single instance storage.
 
> I'm not planning to implement LMTP server anytime soon, but single
> instance storage is planned for dbox format. Maildir-hardlinking in LDA
> could probably implemented while doing it.

Thank you!

Glenn