Postfix using /usr/sbin/sendmail
to send emails.
postfix can be configured as an SMTP-Client which called smtp-relay
method.
Authenticaiton for smtp-relay
using sasl
and we have to create a username/password file with plain auth information and create a Hash database from it. Postfix is using the hashed datapase:
Create Plain Username/Password File /etc/postfix/sasl_passwd
: