incoming mails rejected


Jan 29, 2020
please help me.
A lot of incoming emails (almost all of them) are rejected by PMG with following error message :
May 20 06:12:09 pmg postfix/smtpd[15595]: connect from unknown[]
May 20 06:12:15 pmg postfix/smtpd[15595]: NOQUEUE: reject: RCPT from unknown[]: 554 5.7.1 <>: Recipient address rejected: Rejected by SPF: is not a designated mailserver for (context mfrom, on pmg.ns.lan); from=<> to=<> proto=ESMTP helo=<>
May 20 06:12:21 pmg postfix/smtpd[15595]: disconnect from unknown[] ehlo=1 mail=1 rcpt=0/1 rset=1 quit=1 commands=4/
IP is router in local LAN mikrotik.
Thank you very much in advance
Please ASAP

Stoiko Ivanov

Proxmox Staff Member
Staff member
May 2, 2018
I'd guess that the issue is that your router configuration is problematic:
* the mails look as if they come from the mikrotik IP ( and not from the public internet

I assume that the mikrotik is the device which has the public IP and is doing the NAT for the network and PMG

you need to configure the Mikrotik to forward connections on port 25 to PMG without NATing the source (only the destination)

I don't have experience with Mikrotik - so cannot help you how to achieve that - but look for Port-forwarding ... DMZ, exposed host...

I hope this helps!


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