On 2025-02-10 12:57:24 +0000 (+0000), Alain D D Williams wrote:
Exim tells me "no immediate delivery: more than 30 messages received in one connection"
The emails then sit in the exim queue until a queue runner kicks in - which happens once every 30 minutes. The result is considerable delays which makes list email conversations bouncy.
Question: how do I tell MM3 to send no more than 30 emails in one connection to exim (via SMTP to localhost port 25) ? [...]
There are corresponding configuration options in Mailman and Exim, where you need to make sure that the batch size used by the former is less than the limit set for the latter.
In your mailman configuration (we use a mailman-extra.cfg in our
deployment to selectively extend the default mailman.cfg) add a
[mta] section with a max_recipients: some_integer_value line.
This value needs to be explicitly less than the
smtp_accept_queue_per_connection global setting in your exim4.conf
file.
It seems to me that the config option in Exim is poorly named and
documented, as I've observed that batches of exactly
smtp_accept_queue_per_connection result in queued processing
rather than immediate delivery, which is why mta.max_recipients
must be strictly less, not set equal to it.
Hope that helps!
Jeremy Stanley