As far as i know ISPConfig sends admin mails with the admin email address in the FROM Header. Let's assume it's [email protected] example.com.
If there's an...
Ok, i've secured my server with Lets Encrypt SSL
I have copied that SSL cert for Postfix and other services....
slightly updated version of https://www.howtoforge.com/postfix_spf
debian 9, works aswell on 8
Note that you can handle SPF with...
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