This example covers three mail addresses using two different mail providers (provider1/2).
Configure Postfix
- sudo dpkg-reconfigure postfix
- Set configuration to “Internet with smart host”
main.cf
Add the following lines to /etc/postfix/main.cf:
sender_dependent_relayhost_maps = hash:/etc/postfix/relaymap
smtp_sender_dependent_authentication = yes
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwords
smtp_sasl_security_options = noanonymous
canonical_maps = hash:/etc/postfix/canonical
Configure SMTP relay server from provider
Define the SMTP servers to send mail to. Only one entry for every provider domain is necessary.
Create /etc/postfix/relaymap
@provider1.org smtp-server.provider1.org
@provider2.org smtp-server.provider2.org
Create hash file:
sudo postmap /etc/postfix/relaymap
Configure email adresses sending configuration
Define mail addresses and their passwords to authenticate.
Create /etc/postfix/sasl_passwords
email1@provider1.org email1@provider1.org:PASSWORD
email2@provider1.org email2@provider1.org:PASSWORD
email3@provider2.org email3@provider2.org:PASSWORD
Create hash file:
sudo postmap /etc/postfix/sasl_passwords
Rewrite local addresses to global addresses for sending
Map your local user logins to global mail adresses.
Create /etc/postfix/canonical
root@yourpc.yourlocaldomain.xx email1@provider1.org
anotherlogin@yourpc.yourlocaldomain.xx email2@provider1.org
user3@yourpc.yourlocaldomain.xx email3@provider2.org
Create hash file:
sudo postmap /etc/postfix/canonical
Restart postfix