[Dovecot] Director and backend on the same server

[Timo Sirainen]

On Tue, 2012-05-08 at 12:55 -0600, James Devine wrote:
> I have setup director and a backend dovecot service on the same machine
> using different ports.  The backend service is listening on the default 24,
> 110 and 143 for lmtp, pop3 and imap respectively.  Director is listening on
> 10024, 10110 and 10143 for the same respective services.

I'd make director listen on 24/110/143, so you don't accidentally
connect there when you intended to connect to director, and end up
accessing mails via wrong server.

> I can get this setup to work if I have one backend server on a different IP
> listening on 10024, it seems director tries to use the same port it is
> listening on when making backend connections.
> 
> If I point it to the local backend server, it tries to connect to itself
> which fails.  Is there a way to specify the backend ports that director
> tries to connect to?  I see there is a way to specify the port
> in director_servers but I'm not sure how I would specify the different
> ports for the different backend services, if this is even possible.

The passdb lookup can return which port to connect to. Director only
sets the destination IP, everything else happens the same as with
non-director proxying:
http://wiki2.dovecot.org/PasswordDatabase/ExtraFields/Proxy