2 - Raspberry PI Community Projects

Note that the SASL database was created in Postfix's directory. In order to ensure consistency,
we also turn /etc/sasldb2 into a symbolic link pointing at the database used by Postfix, with
the ln -sf /var/spool/postfix/etc/sasldb2 /etc/sasldb2 command.
Now we need to configure Postfix to use SASL. First the postfix user needs to be added to the sasl
group, so that it can access the SASL account database. A few new parameters are also needed to
enable SASL, and the smtpd_recipient_restrictions parameter needs to be configured to allow
SASL-authenticated clients to send emails freely.
# Enable SASL authentication
smtpd_sasl_auth_enable = yes
# Define the SASL authentication domain to use
smtpd_sasl_local_domain = $myhostname
[...]
# Adding permit_sasl_authenticated before reject_unauth_destination
# allows relaying mail sent by SASL-authenticated users
smtpd_recipient_restrictions = permit_mynetworks,
permit_sasl_authenticated,
reject_unauth_destination,
[...]
Example 11.15
Enabling SASL in /etc/postfix/main.cf
EXTRA
Authenticated SMTP client
Most email clients are able to authenticate to an SMTP server before sending
outgoing messages, and using that feature is a simple maer of configuring
the appropriate parameters. If the client in use does not provide that feature,
the workaround is to use a local Postfix server and configure it to relay email
via the remote SMTP server. In this case, the local Postfix itself will be the
client that authenticates with SASL. Here are the required parameters:
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
relay_host = [mail.falcot.com]
The /etc/postfix/sasl_passwd file needs to contain the username and password
to use for authenticating on the smtp.falcot.com server. Here's an example:
[mail.falcot.com]
joe:LyinIsji
As for all Postfix maps, this file must be turned into /etc/postfix/sasl_
passwd.db with the postmap command.
Chapter 11 — Network Services: Postfix, Apache, NFS, Samba, Squid, LDAP
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