1978

sasldb2

# saslpasswd2 -c -u mail.example.com USERNAME
XXXXXXXXXXXXXXX

# sasldblistusers2
USERNAME@mail.example.com: userPassword

There are too many authentication mechanism against cyrus sasl

mech_list: PLAIN LOGIN CRAM-MD5 DIGEST-MD5 NTLM

Search your package repositories for more info.
In centos 6 you need to install an extra package for every auth mechanism.

## PLAIN and LOGIN authentication support for Cyrus SASL

yum -y install cyrus-sasl-plain

or

## CRAM-MD5 and DIGEST-MD5 authentication support for Cyrus SASL

yum -y install cyrus-sasl-md5

choosing encrypted password

/etc/sasl2/smtpd.conf

# ebal, Sat, 04 Oct 2014 19:11:31 +0300
# pwcheck_method: saslauthd
pwcheck_method: auxprop
auxprop_plugin: sasldb
mech_list: CRAM-MD5 DIGEST-MD5
# mech_list: PLAIN LOGIN CRAM-MD5 DIGEST-MD5 NTLM
# log_level: 7

Postfix

Change ownership on the sasl database

chown postfix:postfix /etc/sasldb2

Add SASL to postfix submission

https://balaskas.gr/wiki/postfix/submission/sasl

Add TLS to postfix submission

https://balaskas.gr/wiki/postfix/submission/TLS