transpot decision based on cyrus mailbox existence

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transpot decision based on cyrus mailbox existence
\ Jack Bates (20 Jul 2007)
. \ mouss (20 Jul 2007)

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5 msg	Postfix + SASL Problem

Subject:	transpot decision based on cyrus mailbox existence
Group:	Postfix-users
From:	Jack Bates
Date:	20 Jul 2007

How can Postfix determine if a Cyrus mailbox exists and deliver with
Procmail if not?

I'm setting up a mail system for a organization where some users want
IMAP mailboxes and others want mail delivered with Procmail
(campcoop.com)

I installed Cyrus IMAP because it's the server with which I'm most
familiar. First I confirmed delivery with Procmail works, then confirmed
delivery to Cyrus with LMTP works. The challenge is using the
appropriate transport depending on whether a Cyrus mailbox exists for
the user.

I've been over documentation for Postfix's numerous transport map
features. I guess if we were using DBMail, for instance, we could use
the MySQL transport map. We maintain user accounts in LDAP, so I tried
at least getting LDAP users' mail delivered to Cyrus and local
/etc/passwd users' mail delivered with Procmail by setting:

fallback_transport = lmtp:unix:/var/run/cyrus/socket/lmtp

However because NSS knows about LDAP users, even LDAP users' mail gets
delivered with Procmail.

Could we maybe use the LDAP transport map to check for the user in LDAP
and deliver to Cyrus if so? Still this is sub-optimal since some LDAP
users don't have Cyrus mailboxes. We could maybe define an LDAP
attribute for the user's transport preference, but then we'd need to set
this preference in addition to creating Cyrus mailboxes. The
organization is quite small and wants maintaining the mail system to be
as simple as possible.

Ideally Postfix would be able to decide whether to deliver to Cyrus
based on whether a Cyrus mailbox existed for the user. Is such thing
possible?

Much thanks! Jack