Mail header Received: from (unknown [xx.xx.xx.xx]) - server has rDNS


I got a problem with one of my servers. The server has reverse DNS points to The server uses this as hostname, and same goes for postfix.
I’ve compared settings with one of my other servers, can’t find any that should explain why I got “unknown” instead of my hostname in my mailheader.

Also a spam test sending mails triggers RDNS_NONE with spamassassin, so it seems to be an issue I need resolved.

When I verify settings in postfix, hostname is indeed there and correct.

Do you guys have any idea about what could be the issue?


Added smtp_bind_address to postfix conf as I’m using a failover ip. Seems to have resolved the issue. Not sure why I needed this on one server, and not on another that is also using same setup with a failover ip.