Replacing sendmail with PostFix

The following are the steps used to replace sendmail with postfix for outbound mail. Many people find postfix easier to configure especially if you have to do smtp authentication.

The following commands will remove sendmail and install postfix:

rpm -e --nodeps sendmail
yum install postfix

Next you want to edit the main configuration file by using the following command:

nano /etc/postfix/main.cf

When all of your edits are done reload postfix with:

service postfix reload

To enable SMTP authentication, add the following lines to the main.cf file:

smtp_sasl_password_maps = hash:/etc/postfix/saslpasswd
broken_sasl_auth_clients = yes
smtpd_sasl_auth_enable = no
smtp_always_send_ehlo = yes
smtp_sasl_auth_enable = yes
smtp_sasl_security_options =

Next edit the password file with the following command:

nano /etc/postfix/saslpasswd

The format of this file is: mailserver login:password
For example:

my.mailserver.com mylogin:mypassword

You then need to create the password database file with the following command:

postmap hash:/etc/postfix/saslpasswd