I want to confirm to SPF and DKIM, this requires me to send email using the IP written in the DNS record of the domain
I have two domains example1.com and example2.com with two IPs 100.0.0.1 and 100.0.0.2 respectively.
How can I configure postfix to always use IP 100.0.0.1 when the send from address is [email protected] and the same to be true for the other domain.
When connecting to the SMTP transport I am using localhost, I know I can configure two postfix instances for each IP and then just connect to the right IP when sending depending on the domain, I would like to see if this can be avoided.
How can this be done?
include:otherdomain.tld
? DKIM has nothing to do with the IP address afaik.Return-Path
sender address given, but not on a 'match' for the latter one on rDNS. That would break all ways of doing mail relay by a 3rd party (e.g. Amazon SES).