Have you added the IP to the spamdyke allowed IP list? /etc/spamdyke/whitelist_ip
From: Todor Petrov <tpet...@vmobile.eu> Reply-To: <qmailtoaster-list@qmailtoaster.com> Date: Thursday, May 25, 2017 at 9:44 AM To: <qmailtoaster-list@qmailtoaster.com> Subject: [qmailtoaster] rdns Hi Eric / all, I have the following problem: I need to open the mailserver for a reporting system from SAP. That system cant use authentication or ssl connection - just a plain communication over 25 - but from inside (protected) network. Of course the traffic is blocked by the spamdyke. I tried to exclude the ip from being checked in the file tcp.smtp, but the error remains. Can anybody please help me to solve this problem? The error message: May 25 16:03:17 mail spamdyke[25033]: DENIED_RDNS_MISSING from: x...@xxx.xxx to: yy...@yyyy.yyy origin_ip: 10.10.10.10 origin_rdns: (unknown) auth: (unknown) encryption: (none) reason: (empty) My tcp.smtp settings for that ip are: 10.10.10.10:allow,RELAYCLIENT="",RBLSMTPD="",SENDER_NOCHECK="1" Best regards, Todor