Debian wheezy had a version of exim4 whose number was
4.7x, maybe even as high as 4.79. With a little help, I got exim
to establish a smtps session with the internet service provider
in our area. The recipe was to:
dpkg-reconfigure exim4-config and be sure to select
mail delivered by smarthost and received via fetchmail or
something comparable.
set passwd.client as follows:
*.suddenlink.net:martin.m@???:somePaSsword
It was also necessary to add a line to
/etc/exim4/conf.d/transport/30_exim4-config_remote_smtp_smarthost
in a certain place that indicated protocol=smtps and then the TLS
magic worked for about 3 years until I upgraded to debian
stretch using exim4 version 4.89. Then the magic black box
broke.
In the first place one can not add protocol=smtps to
/etc/exim4/conf.d/transport/30_exim4-config_remote_smtp_smarthost
as this throws an error now that protocol=smtps is not understood.
Okay. When I leave that out, the conf.autogenerated file
generation code is happy and produces a conf.autogenerated that
indicates we are using port 465 which is true and that the
smarthost is smtp.suddenlink.net which is also good but attempts
to communicate with that host now end instantly as in the
following from /var/log/exim4/mainlog
2018-05-28 19:32:15 1fNL0J-0003CQ-70 H=smtp.suddenlink.net [208.180.40.68]: Remote host closed connection in response to initial connection
2018-05-28 19:32:15 1fNL0J-0003CQ-70 == martin@??? R=smarthost T=remote_smtp_smarthost defer (-18) H=smtp.suddenlink.net [208.180.40.68]: Remote host closed connection in response to initial connection
2018-05-28 19:32:26 1fNSVt-0004AS-HE H=smtp.suddenlink.net [208.180.40.68]: Remote host closed connection in response to initial connection
2018-05-28 19:32:26 1fNSVt-0004AS-HE == wb5agz@??? R=smarthost T=remote_smtp_smarthost defer (-18) H=smtp.suddenlink.net [208.180.40.68]: Remote host closed connection in response to initial connection
I looked in exim's archives in the newer messages and
didn't see anything promising. A search box, there for certain
terms such as smtps and version 4.89 would be nice as this would
probably drill right down to where one needs to go to get the
setup right.
You may wonder; How am I sending this message?
I installed a bare-bones application called msmtp which
does TLS connections and I can once again get to the suddenlink
server. It just works but it is not a substitute for getting
exim4 version 4.89 using the same smarthost.
In the first place, msmtp is no good at all at delivering
local mail such as when one of one's carefully-written
cron jobs or other applications gets in to trouble and cries for
help.
Right now, I can compose an email message using nmh and
cat that file to msmtp by creating a link to it called sendmail
and then cat the message to the fake sendmail with the -t flag to
strip off the addresses.
I suspect the suddenlink.net server is fairly average so
if I just knew what exim needs, I can make it happen but that
kind of documentation for the newer versions seems hard to find.
Here is what I had to tell msmtp to make it work:
tls on
# Don't use starttls.
tls_starttls off
tls_trust_file /etc/ssl/certs/ca-certificates.crt
from martin.m@???
protocol smtp
port 465
# The SMTP smarthost.
host smtp.suddenlink.net
user martin.m@???
password ThePassword
I did try exim4 -d -M msgid but the failur message about
the server closing wasn't any more detailed such as; What di I
send and what did the server do after that? These are usually
essential parts of debugging and TLS is a black box that even if
you know basically what it is doing, when it goes wrong it is
like the "Check Engine" light on a car. Thirty-thousand parts
humming along and one of them has gone bad. Go figure!
I would be happy with having enough plain English
instructions to make the black box work again so exim4 can do
it's great jobs of handling both local and external messages.
Many thanks for any and all constructive suggestions.
Martin McCormick