Configuring exim4 in Ubuntu to use GMail for SMTP

Update:

Please read the comments especially if you run into problems. They contain some valuable information which I can't integrate into the guide because of lack of time to test it. Also GMail has limit of 100 messages/day/account when you use SMTP. Keep this in mind :)

This blog runs on wordpress and the "comment notifications by email" never worked. Initially I thought it was a wordpress problem and trawled through forum posts looking for a solution. Unable to find one I did something which I should have tried right at the beginning. I tried sending a mail from the server using the 'mail' command. Oops !. Exim log(/var/log/exim4/mainlog) give the wonderfully worded message R=nonlocal: Mailing to remote domains not supported

Also I wanted to route the mail through GMail SMTP servers since that would improve reliability. Turns out there is an indeed a way to make exim, the default MTA in debain/ubuntu to route all mail through GMail SMTP servers. Second round of trawling the interwebs started I managed to get a working setup without much trouble. But I had to piece together the content from separate sources. Here is how I did it.

Step 1

Run dpkg-reconfigure exim4-config

Choose mail sent by smarthost; received via SMTP or fetchmail
Type System Mail Name: e.g. company.com
Type IP Adresses to listen on for incoming SMTP connections: 127.0.0.1
Leave Other destinations for which mail is accepted blank
Leave Machines to relay mail for: blank
Type Machine handling outgoing mail for this host (smarthost): smtp.gmail.com::587
Choose NO, don't hide local mail name in outgoing mail.
Chose NO, don't keep number of DNS-queries minimal (Dial-on-Demand).
Choose mbox
Choose NO, split configuration into small files
Mail for postmaster. Leaving blank will not cause any problems though it is not recommended

Step 2

Open the file /etc/exim4/exim4.conf.template
Find the line .ifdef DCconfig_smarthost DCconfig_satellite and add the following in that section
```
   send_via_gmail:
       driver = manualroute
       domains = ! +local_domains
       transport = gmail_smtp
       route_list = * smtp.gmail.com
```
If you have any other smarthost defined with "domains = ! +local_domains" remove that smarthost.
Find the "begin authenticators". In that section add the following
```
   gmail_login:
       driver = plaintext
       public_name = LOGIN
       client_send = : yourname@gmail.com : YourGmailPassword
```
Make sure you have no other authenticators with the same public_name (LOGIN). Comment them out if needed (Thanks Jakub for reminding me)

Find the comment "transport/30_exim4-config_remote_smtp_smarthost". In that section add

   gmail_smtp:
       driver = smtp
       port = 587
       hosts_require_auth = $host_address
       hosts_require_tls = $host_address

Step 3

Run update-exim4.conf
Do /etc/init.d/exim4 restart

That should be it. You can test by using the command line mail client.

Run mail user@example.com
Give a subject and press enter
Type something and press enter
Type a single . (dot) and press enter
Press enter for a blank CC:

This was on an Ubuntu server. I believe that this instructions will also work on Debain without any need for modifications.

Configuring exim4 in Ubuntu to use GMail for SMTP

Update:

Step 1

Step 2

Step 3

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