> On Jan 3, 2019, at 5:23 AM, Lorenzo Milesi <max...@lorenzomilesi.it> wrote:
>
> I need to limit the maximum number of outgoing SMTP connections done by
> Postfix for delivering messages.
> Our VPS provider is limiting to 5 conns/s, so I need Postfix not to open more
> than 5 connections to remote SMTP servers.
You're asking for a Postfix feature that does not exist. For your
use-case to work, the Postfix queue manager would need to put all
mail in a single in memory queue, regardless of the destination
nexthop. With:
mumble_destination_recipient_limit = 1
Postfix create fragments the queue by (nexthop, recipient) rather
than just the nexthop. You're looking for a feature that ignores
both the nexthop and the recipient aggregates all nexthops into a
single unified transport-wide queue. No code for that exists.
Frankly, running a bulk mail MTA from a service that only allows
5 connections/sec is probably in violation of the service terms,
and in any case much too tight a straightjacket for Postfix,
which is written to be secure *and* performant. There's only so
much support for extreme measures to make Postfix slow.
So for now my best advice is: https://dilbert.com/strip/1995-06-24
--
Viktor.
