postfix

Using a relay host

These are the basic steps to set up Postfix to use SMTP Authentication to send mail through a relay host.

Set up a password maps file (/etc/postfix/sasl_passwd) as follows:

mail.ispserver.com    username:password
# chown root:root /etc/postfix/sasl_passwd
# chmod 600 /etc/postfix/sasl_passwd
# postmap /etc/postfix/sasl_passwd

Append the following lines to /etc/postfix/main.cf:

relayhost = mail.ispserver.com
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options =

Finally reload postfix:

# postfix reload

That should do it!