From 7ccd6e1348321491ebcb2c6afec7be1de395e926 Mon Sep 17 00:00:00 2001 From: Julien Rabier Date: Mon, 11 May 2020 21:37:17 +0000 Subject: [PATCH] fix destination concurrency Hi, Postfix has this very peculiar behavior where the target of some config keys changes depending on the value. Here, if `smtp_destination_concurrency_limit` is set to 1, then according to http://www.postfix.org/postconf.5.html#default_destination_concurrency_limit it doesn't mean "1 concurrent mail per domain, but per recipiend address". So, if set to 1, it means we can send any volume of e-mails concurrently (with a 5s delay) if all recipient addresses are different. In order to avoid this, we should increase the value to restore the expected behavior (concurrency per domain, not per recipient). --- data/templates/postfix/main.cf | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/data/templates/postfix/main.cf b/data/templates/postfix/main.cf index 61cbfa2e6..18e457a76 100644 --- a/data/templates/postfix/main.cf +++ b/data/templates/postfix/main.cf @@ -170,7 +170,7 @@ smtpd_milters = inet:localhost:11332 milter_default_action = accept # Avoid to send simultaneously too many emails -smtp_destination_concurrency_limit = 1 +smtp_destination_concurrency_limit = 2 default_destination_rate_delay = 5s # Avoid email adress scanning