My Postfix in Ubuntu

With postfix, you'll be able to receive emails from your localhost. Here's how I go about it.

Installing

sudo apt-get install postfix

For me, the option to "General type of configuration", I choose "Satellite system".

Settings

I'm going to use Google mail server here. You need to change the relayhost if you're not using gmail.

sudo vim /etc/postfix/main.cf

relayhost = [smtp.gmail.com]:587
smtp_use_tls = yes
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options = noanonymous
smtp_tls_CAfile = /etc/postfix/cacert.pem

Copy the certificate, it's optional but better we do it.

cat /etc/ssl/certs/Thawte_Premium_Server_CA.pem | sudo tee -a /etc/postfix/cacert.pem

Set the credential to Google mail server.

sudo vim /etc/postfix/sasl_passwd

[smtp.gmail.com]:587 [username]@gmail.com:[password]

sudo postmap /etc/postfix/sasl_passwd

Securing your password

sudo chmod 400 sasl_passwd.db

Finally, restart Postfix.

sudo service postfix restart

Testing

Install mailutils if you have not.

sudo apt-get install mailutils

Your choice of using mail or mailx.

echo "this is a test mail." | mail -s "test" your@email.com

echo 'It works!' | mailx -s 'hello world' your@email.com

Checking the log to see if anything goes wrong

tail -f /var/log/mail.log

Troubleshooting

Must issue a STARTTLS command first.

You're missing smtp_use_tls = yes in main.cf.