email builder: > > Hello, > > I have two IP addresses on my server and would like to serve a different SSL > (TLS) certificate for each one. I think all the other configuration will not > need to differ between the two, so I think running multiple instances of > postfix would be overkill (?). > > I want to confirm that it would be possible/viable/advisable to simply create > two smtpd processes in master.cf: > > > 1.2.3.4:smtp inet n - n - - smtpd > -o myhostname=mail.domainA.com > -o mydomain=domainA.com > -o smtpd_tls_cert_file=/etc/postfix/domainA.crt > -o smtpd_tls_key_file=/etc/postfix/domainA.key > > 4.3.2.1:smtp inet n - n - - smtpd > -o myhostname=mail.domainB.com > -o mydomain=domainB.com > -o smtpd_tls_cert_file=/etc/postfix/domainB.crt > -o smtpd_tls_key_file=/etc/postfix/domainB.key
The rest of Postfix needs to know where it should deliver mail for mail.domainB.com, domainB.com, mail.domainA.com, and domainA.com. Otherwise, the Postfix SMTP server will reject mail with "relay access denied", and the Postfix SMTP client will reject mail with that "mail loops back to myself". Note that the Postfix SMTP server does not make all decisions by itself. It relies on the trivial-rewrite service to decide how a domain should be handled. There is no official support for multiple domain personalities. Wieste