Friday, July 31, 2009

HOWTO :'s Relay Mail Server with Postfix on Ubuntu 9.04 Server

Your Internet Services Provider (ISP) may block SMTP port (Port 25) if you are not using a business plan (like in Hong Kong). However, you can still send email with reverse lookup of your domain name when your domain registrar is

Step 1 :

Create and enable your free email account at when you have a domain name there. Set the password accordingly. Your username of the account may be look like this : yourname@yourdomain.

Incoming Mail Server Type : POP3
Incoming Mail Server :
Incoming Mail Server Port : 110

Outgoing Mail Server :
Outgoing Mail Server Port : 25, 80, 587 or 3535

Step 2 :

Create a file namely "sasl_passwd".

sudo nano /etc/postfix/sasl/sasl_passwd

Add the following line. username:password

Step 2a :

Save and quit. Issue the following commands.

chown root:root /etc/postfix/sasl/sasl_passwd
chmod 600 /etc/postfix/sasl/sasl_passwd
postmap /etc/postfix/sasl/sasl_passwd

Step 3 :

Go to your mail server (Postfix).

sudo nano /etc/postfix/

Edit or/and add the following lines.

relayhost = []
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl/sasl_passwd
smtp_sasl_security_options = noanonymous
mynetworks =, [::ffff:]/104 [::1]/128

*If your network is, otherwise; change it accordingly.

Step 4 :

Restart the Postfix to make it work.

sudo /etc/init.d/postfix restart

Step 5 :

Now, you can send email with reverse lookup via's relay mail server. Your email will not be blocked or redirected to "Junk Mail" folder by Gmail, Yahoo Mail or others.

Be keep in mind that you have 250 quota every day. Or, you are required to purchase more quota.

Point to your email server on other servers that will send email.

That's all. See you!