[CentOS] postfix pb with mass emails

Mon Sep 4 08:49:07 UTC 2006
sophana <sophana at zizi.ath.cx>


I'm hosting a forum (phpbb) with more than 3500 users with centos 4.3.
The forum admins would like to send an email to its (3500) users. I
configured phpbb to use smtp (postfix-2.1.5-4.2.RHEL4.mysql.centos4) to
send the email.
I raised the max destination limit from 1000 to 5000, and made a test.
Here the disaster began:
Majority of the users received from 20 to 50 emails.
Looking at the logs, postfix divided the email into several ones with 50
recipient each (as documented). I think the problem was that when one of
the recipients was unreachable, the mail went into defered state, to be
retried later. The problem (bug?) is that the mail was sent again to all
50 recipients, explaining why so many users received lot of mails.
Anyone had a similar problem?
Any suggestion for that?