Sender Rewriting Scheme (SRS) is a scheme for rewriting the envelope sender address of an email message, in view of remailing it. This function (re)allow you to forward email on a server with SPF enabled. SPF ensure that the server who sends an email is allowed to send it from this domain. If you forward a mail, SPF will fail as your server is not allowed to send email from the domain of the forwarded email. SRS solve this issue. (more…)
Before starting this post I want to thanks Ilija from matoski.com as this post is based on his work on SPF / DKIM for Debian. Click here to see the original post.
Let’s start with a very short description of DKIM. DomainKeys Identified Mail is a mechanism designated to detect email spoofing (i.e. be sure that the original email content is the same as the received). It works with signatures. The public key is available on a DNS entry of the sender domain zone and the private key used to generate this signature is stored on the mail server.
This post will show how to configure DKIM on a Debian server with Postfix and automatize the configuration with Plesk. I assume you have sufficient permission to run these commands. (more…)