Configuring Postfix to use SASL Authentication

Description:

Mstar.net requires mail clients to use authentication in order to send mail.
This document details how to configure a Linux machine to send mail through
mail.mstar2.net using postfix and SASL authentication (also known as SMTP
AUTH).

Assumptions:

1. Computer is running the postfix mail program (a secure sendmail replacement)
2. postfix was compiled with SASL authentication support. The postfix that
   comes with Red Hat 8.0 has SASL enabled.
3. You are using an account on the home Linux machine that is the same name as
   the account that you have with Mstar.

Steps:

A. Edit postfix configuration files and add the following:

  /etc/postfix/main.cf:

    relayhost = mail.mstar2.net
    myorigin = mstar2.net
    enable_sasl_authentication = yes
    smtp_sasl_auth_enable = yes
    smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
    smtp_sasl_security_option =
  
  /etc/postfix/sasl_passwd:

    mail.mstar2.net	my_ISP_username:my_ISP_password

B. Run the following commands:
  chmod o-r /etc/postfix/sasl_passwd
  postfix check
  postmap /etc/postfix/sasl_passwd
  postfix reload
  tail /var/log/maillog  # use this to see error messages

Helpful postfix SASL links:
  http://sdb.suse.de/en/sdb/html/rsimai_imap_smtp_auth.html
  http://www.postfix.org/smtpd.8.html

RFC links:
  SASL:           ftp://ftp.isi.edu/in-notes/rfc2222.txt
  SMTP AUTH:      ftp://ftp.isi.edu/in-notes/rfc2554.txt
  Anonymous SASL: http://www.faqs.org/rfcs/rfc2245.html