On Tue, Jul 06, 2010 at 11:22:47PM +0200, Fran Garcia wrote:
> >> - Allow multidomain
> >
> > I don't know what this means.
>
> Hi Viktor, thanks for your reply.
>
> This means "be able to hold several virtual domains as destination".
> Think of an ISP configuring a shared email platform for several
> domains / customers. Ideally those domains would be held in LDAP as
> well. (I've seen the qmail.schema and apparently is only ready fo one
> single domain).
Postfix supports multiple domains not via pre-fab LDAP schemas,
but via decisions about local and virtual users as described in
http://www.postfix.org/VIRTUAL_README.html
you can implement "virtual alias" or "virtual mailbox" users in as many
domains as you wish, via any LDAP schema that contains the required
address -> value (either address of mailbox path) mappings.
> >> - Host transports for each defined account / email address.
> >
> > This is not a good idea. Avoid using LDAP for transport lookups.
> > Instead:
> >
> > ? ?- rewrite envelope recipients to an appropriate destination
> > ? ? ?domain via virtual(5) (i.e. virtual_alias_maps).
> >
> > ? ?- explicitly set virtual_alias_domains (even if empty).
> >
> > ? ?- Map each destination domain to a suitable transport via
> > ? ? ?an indexed file (Berkeley DB hash or btree, CDB, ...)
>
> The rationale for requesting this was "how do I grow if I have say
> 100k accounts in a single domain and I want to spread the load on
> several backend servers". As per your description, that would be
> handled like : us...@example.org ->
> us...@internal_backendx.example.org ?
Yes.
> >> - Integrate with dovecot and/or cyrus-imapd.
> >
> > Postfix will happily use any schema in which lookup keys
> > (typically email addresses) can be mapped to a result
> > value (or list of values which are transformed to a comma-separated
> > result string) by a query as explained in:
> >
> > ? ?http://www.postfix.org/ldap_table.5.html
> > ? ?http://www.postfix.org/LDAP_README.html
> >
> > Postfix has no preferred LDAP schemas, it operates at a higher level of
> > abstraction, i.e. virtual_alias_maps, transport_maps, ... ?which can be
> > implemented via LDAP if you so choose. The mapping between an actual
> > LDAP dataset and the conceptual Postfix key/value table is up to you.
>
> Thanks for the links :-) . I already came across the "postfix adapts
> to any ldap schema" but, since I'm starting with ldap and not very
> familiar with all the concepts, I wanted to get some reall ife
> examples of actual schemas people are using.
Design the Postfix configuration first, and the LDAP schema second.
--
Viktor.
