Here is quick guide on how I configured Exim 4 to let a Debian Squeeze server send mails through a GMail account. This article is just a rip-off of a tutorial I found on the web, which is itself an updated version of a Debian’s Wiki page.
Debian come with Exim (v4.72) pre-installed: it’s the default MTA on this distribution. There is absolutely no need to install extra packages. Let’s start right away by calling Exim’s configuration wizard:
1 $ dpkg-reconfigure exim4-config
Here are the options I choose in each step of the wizard:
Choose Mail sent by smarthost; received via SMTP or fetchmail.
System mail name: server.deldycke.com.
IP addresses to listen on for incoming SMTP connections: 127.0.0.1 ; ::1 (which is the default proposed value).
Other destinations for which mail is accepted: leave blank.
Machines to relay mail for: leave blank.
Machine handling outgoing mail for this host (smarthost): smtp.gmail.com::587.
Hide local mail name in outgoing mail: No.
Keep number of DNS-queries minimal (Dial-on-Demand): No.
Mailboxes format: mbox.
Split configuration into small files: No.
All these parameters you just answered are saved in the /etc/exim4/update-exim4.conf.conf:
# /etc/exim4/update-exim4.conf.conf
#
# Edit this file and /etc/mailname by hand and execute update-exim4.conf
# yourself or use 'dpkg-reconfigure exim4-config'
#
# Please note that this is _not_ a dpkg-conffile and that automatic changes
# to this file might happen. The code handling this will honor your local
# changes, so this is usually fine, but will break local schemes that mess
# around with multiple versions of the file.
#
# update-exim4.conf uses this file to determine variable values to generate
# exim configuration macros for the configuration file.
#
# Most settings found in here do have corresponding questions in the
# Debconf configuration, but not all of them.
#
# This is a Debian specific file
dc_eximconfig_configtype='smarthost'
dc_other_hostnames=''
dc_local_interfaces='127.0.0.1 ; ::1'
dc_readhost=''
dc_relay_domains=''
dc_minimaldns='false'
dc_relay_nets=''
dc_smarthost='smtp.gmail.com:587'
CFILEMODE='644'
dc_use_split_config='false'
dc_hide_mailname='false'
dc_mailname_in_oh='true'
dc_localdelivery='mail_spool'Then I updated the /etc/exim4/exim4.conf.template to add proper handling of GMail SMTP server. Here are the differences between the untouched original exim4.conf.template file and my version:
--- /etc/exim4/exim4.conf.template-orig 2011-05-03 10:49:43.207938577 +0200
+++ /etc/exim4/exim4.conf.template 2011-05-03 10:52:26.235438776 +0200
@@ -1077,15 +1077,11 @@
# domains, you'll need to copy the dnslookup_relay_to_domains router
# here so that mail to relay_domains is handled separately.
-smarthost:
- debug_print = "R: smarthost for $local_part@$domain"
- driver = manualroute
- domains = ! +local_domains
- transport = remote_smtp_smarthost
- route_list = * DCsmarthost byname
- host_find_failed = defer
- same_domain_copy_routing = yes
- no_more
+send_via_gmail:
+ driver = manualroute
+ domains = ! +local_domains
+ transport = gmail_smtp
+ route_list = * smtp.gmail.com
.endif
@@ -1632,6 +1628,12 @@
# to a smarthost. The local host tries to authenticate.
# This transport is used for smarthost and satellite configurations.
+gmail_smtp:
+ driver = smtp
+ port = 587
+ hosts_require_auth = $host_address
+ hosts_require_tls = $host_address
+
remote_smtp_smarthost:
debug_print = "T: remote_smtp_smarthost for $local_part@$domain"
driver = smtp
@@ -1759,6 +1761,11 @@
begin authenticators
+gmail_login:
+ driver = plaintext
+ public_name = LOGIN
+ client_send = : [email protected] : XXXXXXXXX
+
#####################################################
### end auth/00_exim4-config_header
@@ -1999,27 +2006,27 @@
^${sg{PASSWDLINE}{\\N([^:]+:)(.*)\\N}{\\$2}}"
.endif
-login:
- driver = plaintext
- public_name = LOGIN
-.ifndef AUTH_CLIENT_ALLOW_NOTLS_PASSWORDS
- # Return empty string if not non-TLS AND looking up $host in passwd-file
- # yields a non-empty string; fail otherwise.
- client_send = "<; ${if and{\
- {!eq{$tls_cipher}{}}\
- {!eq{PASSWDLINE}{}}\
- }\
- {}fail}\
- ; ${extract{1}{::}{PASSWDLINE}}\
- ; ${sg{PASSWDLINE}{\\N([^:]+:)(.*)\\N}{\\$2}}"
-.else
- # Return empty string if looking up $host in passwd-file yields a
- # non-empty string; fail otherwise.
- client_send = "<; ${if !eq{PASSWDLINE}{}\
- {}fail}\
- ; ${extract{1}{::}{PASSWDLINE}}\
- ; ${sg{PASSWDLINE}{\\N([^:]+:)(.*)\\N}{\\$2}}"
-.endif
+#login:
+# driver = plaintext
+# public_name = LOGIN
+#.ifndef AUTH_CLIENT_ALLOW_NOTLS_PASSWORDS
+# # Return empty string if not non-TLS AND looking up $host in passwd-file
+# # yields a non-empty string; fail otherwise.
+# client_send = "<; ${if and{\
+# {!eq{$tls_cipher}{}}\
+# {!eq{PASSWDLINE}{}}\
+# }\
+# {}fail}\
+# ; ${extract{1}{::}{PASSWDLINE}}\
+# ; ${sg{PASSWDLINE}{\\N([^:]+:)(.*)\\N}{\\$2}}"
+#.else
+# # Return empty string if looking up $host in passwd-file yields a
+# # non-empty string; fail otherwise.
+# client_send = "<; ${if !eq{PASSWDLINE}{}\
+# {}fail}\
+# ; ${extract{1}{::}{PASSWDLINE}}\
+# ; ${sg{PASSWDLINE}{\\N([^:]+:)(.*)\\N}{\\$2}}"
+#.endif
#####################################################
### end auth/30_exim4-config_examples
#####################################################Now all we have to do is to regenerate Exim’s configuration and restart the mail server:
1$ update-exim4.conf2$ /etc/init.d/exim4 restart
You can then send a dummy email to test your mail system:
1$ mail [email protected]2Subject: This is an exim test3.4Cc:5Null message body; hope that's ok
And check in the log that everything’s fine:
1$ tail -F /var/log/exim4/mainlog22011-05-03 10:56:32 1QHBPE-0000ne-CW <= [email protected] U=root P=local S=36232011-05-03 10:56:36 1QHBPE-0000ne-CW => [email protected] R=send_via_gmail T=gmail_smtp H=gmail-smtp-msa.l.google.com [209.85.227.109] X=TLS1.0:RSA_ARCFOUR_SHA1:16 DN="C=US,ST=California,L=Mountain View,O=Google Inc,CN=smtp.gmail.com"42011-05-03 10:56:36 1QHBPE-0000ne-CW Completed