PostFix Sender-based Routing
If you want to use a more fine-grained model you can choose to relay the outgoing traffic for domains over separate users. This allows you to apply different settings per domain, but also provides the end user access to their own logfiles.
- Create a
sasl_passwd
file for the individual outgoing user(s) containing the following data, filled in with the user credentials: - Create a
sender_relay
file containing the following data, filled in with the domain and smarthost details: - Postmap both files:
- Add the following information to the
main.cf
file, ensuring this is populated with the appropriate smarthost: - Restart PostFix
@demo-domain.invalid outgoing@demo-domain.invalid:THEPASSWORD
@demo-domain.invalid [SMARTHOST1]:587
@domain-alias.invalid [SMARTHOST2]:587
postmap /etc/postfix/sasl_passwd
postmap /etc/postfix/sender_relay
relayhost = [SMARTHOST]:587
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options =
smtp_sender_dependent_authentication = yes
sender_dependent_relayhost_maps = hash:/etc/postfix/sender_relay
The above extract also configures server-wide, to also filter those that are not added on the sender_relay
file. If you do not want this and only want to filter specific domains remove the relayhost
line from above