[Dovecot] IMAP/POP3 server with proxy feature

[Christian Froemmel]

On Sat, 3 Feb 2007, Chris Wakelin wrote:

Hi,

> I don't think you need that particular feature. As far as I know just
> use a passdb with extra-fields and have "proxy=y" defined for the users
> you want to proxy. I think this is pretty stable.

We use the proxy-feature currently to migrate from one server to another.  
Works (mostly) like a charm. The only thing (for which I start a new
thread) is a crash in the pop3-proxy, when courier (as the real
imap-server) just drops the connection. (The thing I didn't thought of was
the MAXPERIP-limit (defaults to 4) in courier-imap. But with proxying
EVERY connection comes from one IP, and then courier just drops the
connection - which leads to the crash I will report.)

Everything else is rock-stable and _fast_. So my next migration is to drop
courier-imap for dovecot.

We have the following auth-section in the dovecot.conf

auth default {
        mechanisms = plain
        userdb static {
                args = static uid=5000 gid=5000 home=/dev/null
        }
        passdb sql {
                args = /usr/local/dovecot/etc/sql.conf
        }
        user = root
        count = 2
}

the userdb-section (I think it was suggested in the wiki) is purely
fictional, the uid/gid doesn't even exist.

In the sql.conf we have "static" SQL-Lookup (derivated from a former
requirement) for the password-query:

SELECT NULL AS password, '111.222.111.222' as host, NULL AS destuser, 'Y' 
AS nologin, 'Y' AS nodelay, 'Y' AS proxy

For this query you even don't have to have a filled table, just a db-login
is required. I am not brave enough to test further if there is a database
needed (we have a dummy-db configured) as it is in heavy use.

regards,
Christian
-- 
SYSTEM CONCEPT GmbH