On Thu, Jun 17, 2010 at 06:55:33PM +0200, Carlos Velasco wrote:
> > Loop detection is on by default when the destination port is 25.
> > Loop detection matches on either banner hostnames or interfaces
> > or IP addresses found in inet_interfaces or proxy_addresses.
>
> It could be good to have a switch to turn it off for cases like this :)
>
> > Alternatively, you can override "inet_interfaces" for just the
> > smtp(8) delivery agent:
> >
> > smtp unix ... smtp
> > -o inet_interfaces=127.0.0.1
>
> I think I will go with this as this one doesn't need smtpd to listen on
> 127.0.0.1:25.
I think this is a mistake, in the sense that it is a crude work-around.
The right solution is keep the "inet_interfaces" settings of Postfix
instances *disjoint*, and to never forward mail to port 25 *within*
an instance. This keeps things clear and predictable.
- Each instance "owns" a separate pool of IPs
- Internal forwarding is never to port 25, that's
where outside mail comes in, and you never loop
it back-in again.
- Loop detection is not disabled.
Don't fight the system, work within the design.
--
Viktor.
