Use GMail as an SMTP relay using SSMTP

On some of your home workstations, and especially on a laptop, setting up a full-blown SMTP server such as Postfix, Sendmail, or Exim might be overkill.  Follow the jump to learn how to setup the lightweight ssmtp to relay all outbound mail through your GMail account by using Gmail as a smarthost.

SSMTP is meant to be a no-frills, secure, and lightweight replacement for a full-blown MTA. Personally, I feel it's best use is on a laptop where you're moving around between networks a lot, and need to send outbound emails from cron or other shell scripts.

By setting up SSMTP, it doesn't matter where you are, sending mail will be sent out over encrypted SMTP to Google's gmail servers. After handing it off, Google's servers do all the routing for you.

Setting up SSMTP is quick and easy - let's get to it. On Ubuntu, run:

sudo apt-get install ssmtp mailx

Now, we just need to configure SSMTP. Open up /etc/ssmtp/ssmtp.conf in your favorite editor, and add or update the following lines:

#The following line redirects mail to root to your gmail account
root=myemail@gmail.com
mailhub=smtp.gmail.com:587
UseSTARTTLS=yes
UseTLS=yes
AuthUser=myemail@gmail.com
AuthPass=mypassword

That's it! Now, let's try testing it:

echo "This is a test message." | mailx -s 'Test Message' myemail@gmail.com

You should now be all setup and ready to go!