So I have several servers all set up to send and receive mails from multiple domains, this all works perfectly fine.
However a few people have complained that within the mail headers you still see the name of the server being used, we'll call it "mail1.example.com". They can send and receive mail fine, it's showing their email addresses, using the right DKIM reports etc but they don't like having to have SPF records within their DNS specifically for my server or the headers.
Is it possible in any way with Postfix to "virtualise" the usage of "myhostname" so that it can pic/choose which server name to use?