The transport file can't handle multiple result values.

Per the Postfix author on December 9, 2005:

I am revising the SMTP client connection management code, and it
is so ridiculously complicated that there will not be multi-nexthop
support in the forseeable future.

Wietse

Sure would be nice though.

--
Greg



Adam wrote:
> I'm trying to set up a mail gateway with postfix, which will sit in our
> DMZ and just forward all mail through to our internal servers.
>
> I'm putting the domain name in relay_domains and then the internal
> server name in the transport file, specified by transport_maps. The
> problem I have is that I want postfix to use more than one destination
> for relaying, to guard against failure of one of the internal machines.
> The syntax:
>
> example.com smtp:[internal_mail.example.com]
>
> only allows me to give one server.
>
> Is there a way of giving multiple servers here, and having postfix
> either 'load balance' between them or use the second if the first
> fails?
>
> I realise that I could omit the '[]' and using MX lookups, but this
> would mean getting custom MX records to the gateway machine, which I'm
> not keen on.
>
> Thanks for any help
>