This is the default example configuration of smtpd.conf provided by Postfix. This config file was generated by Postfix running on CentOS 6.
It is located under: /etc/sasl2/smtpd.conf
pwcheck_method: saslauthd
mech_list: plain login
Download the raw file with wget or curl
wget -O smtpd.conf.example http://exampleconfig.com/static/raw/postfix/centos6/etc/sasl2/smtpd.conf
curl http://exampleconfig.com/static/raw/postfix/centos6/etc/sasl2/smtpd.conf > smtpd.conf.example
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