/var/log/maillog is flooded because of haproxy health checks. To stop the flood I changed syslog.conf:
$ grep mail /etc/syslog.conf *.err;kern.warning;auth.notice;mail.crit /dev/console *.notice;authpriv.none;kern.debug;lpr.info;mail.crit;news.err /var/log/messages mail.warning;local5.warning /var/log/maillog #mail.*;local5.* /var/log/maillog #mail.*; /var/log/maillog Initially I had `mail.*` activated (local5 is dovecot). Obviously, setting `mail.warning`, on the one hand, reduces the logs i.e., health checks are no longer logged. On the other hand, quite a lot of information also gets missing: not only the connection information from haproxy but also from any other SMTP connection attempt. On FreeBSD, syslog cannot filter according to the log message content. So I'm wondering whether there is something I can do on Postfix's side not to log connection from a specific IP/from haproxy health checks. I have already set smtpd_upstream_proxy_protocol = haproxy Thank you for your help. Niklaas