From a88db53786768309e9f88840231e5812506535bf Mon Sep 17 00:00:00 2001 From: Guilhem Moulin Date: Thu, 6 Dec 2018 19:22:10 +0100 Subject: =?UTF-8?q?postfix=20=E2=89=A53.0:=20don't=20advertise=20SMTPUTF8?= =?UTF-8?q?=20support.?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We're relaying messages to our LMTP daemons (Dovecot, Amavisd) and some downstream SMTP servers, not all of which are under our control. Forwarding messages with UTF-8 envelope addresses or RFC 5322 headers yields undeliverable messages, and the bounces make us a potential backscatter source. So it's better to disable SMTPUTF8 at this point. Cf. also http://www.postfix.org/SMTPUTF8_README.html and https://unix.stackexchange.com/questions/320091/configure-postfix-and-dovecot-lmtp-to-receive-mail-via-smtputf8 . See also upstream's comment at https://marc.info/?l=postfix-users&m=149183235529042&w=2 : “Perhaps SMTPUTF8 autodetection could be more granular: UTF8 in the envelope is definitely problematic for a receiver that does not support SMTPUTF8, while UTF8 in a message header is less so.” --- roles/common/templates/etc/postfix/main.cf.j2 | 1 + 1 file changed, 1 insertion(+) diff --git a/roles/common/templates/etc/postfix/main.cf.j2 b/roles/common/templates/etc/postfix/main.cf.j2 index 92a3340..20ef917 100644 --- a/roles/common/templates/etc/postfix/main.cf.j2 +++ b/roles/common/templates/etc/postfix/main.cf.j2 @@ -9,6 +9,7 @@ biff = no readme_directory = no mail_owner = postfix compatibility_level = 2 +smtputf8_enable = no myorigin = /etc/mailname myhostname = {{ ansible_fqdn }} -- cgit v1.2.3