> This is an old issue I have and would like to get feedback on.
>
> several months ago , I have seen error "more than 10 messages received in
> one connection". Upon investigation , I increased it to 200 by adding
> "smtp_accept_queue_per_connection=200" to config file.
>
> Every now and then , I see same error on log file with new count "more than
> 200 messages received in one connection" , some of emails get delivered 30
> minutes later.
>
> What are options I have to remediate this issue and get mail delivered
> immediately ?
Well, one obvious solution is to increase
smtp_accept_queue_per_connection to a very large number, since clearly
some of the servers connecting to you are delivering more than 200
messages in a single connection.
However, your mention of a 30 minute delay suggests that you may also
want to configure your system to perform an Exim queue run more than
once every 30 minutes. How this is done is system dependent, because
it is an Exim command line argument; on Debian and Ubuntu systems, for
example, you change /etc/default/exim4 to adjust the 'QUEUEINTERVAL'
setting. We use:
QUEUEINTERVAL='5m'
People who want very fast (re)delivery at all costs can lower this
even further, although be aware of potential adverse impacts if you
ever have a large queue full of messages that are frequently retried.
(By this I mean 'you might wind up with so many active queue runner
processes that your system explodes'. You will want to look into various
potential limits here; see the Exim documentation.)
- cks
