Jozsef Kadlecsik:
> Hello,
>
> We plan to add the possibility for our users to choose that messages
> categorized as spam are put on the hold queue instead of the default
> reject. Thus it'll be possible to release the false positives, which
> can make life easier for them.
>
> Currently I can see two ways to accomplish it, both have got pros and
> cons.
>
> a. Single postfix instance with large enough queue partition. Easier,
> simpler, however if the queue partition becomes full, the normal
> traffic is blocked as well.
>
> b. Two postfix instances, the first one sends the messages to be held
> to the second one via a selected transport. (Two policy daemons are
> required as well.) The first instance handles all the good traffic
> and diverts the bad one to the second instance, which has the single
> job to put messages onto its hold queue and release from there.
> That way the hold queue can be separated and moved to a second
> partition. Still, if the second instance stops working for whatever
> reason, the messages to be held will stuck at the first instance.
>
> How could one achieve that the held messages are separated from the normal
> traffic (i.e. hold queue on another partition), but if the messages cannot
> be held, then those gets rejected instead of queued?
Given Postfix's architecture, a loosely-coupled pipeline without
global feedback, there is no obvious way to build global feedback
into Postfix itself.
I suggest that you run an email monitoring system. When the secondary
system stops accepting mail for more than some minimum amount of
time (allowing enough time for the system to reboot), update the
configuration on the primary system.
Wietse
