A better understanding of the the whitelist and mail filter.

Jacky Li

Member
Jan 15, 2019
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Hi,

I have this user with problem with DNS record problem as below. I have setup proxmox to block unknown clients. I created a whitelist on the mail filter and add the iitm.ac.in domain as a regrex expression. However, emails are still getting rejected. Am I suppose to put it in the Mail Proxy - Whitelist section? On the same topic, I want to bypass check on helo or SPF on some domain, where should I put the entries? In the documentation on Whitelist, it said "All SMTP checks are disabled for those entries (e. g. Greylisting, SPF, RBL, …) " Does it also mean unknown clients/senders, and HELO checks? What if I want to disable spam/virus checks for a specific receiver, I guess I have to create the mail filter rules for the specific receiver right? Thank you very much.

Mar 9 07:15:15 pmx01postfix/smtpd[3930]: warning: hostname acharya.iitm.ac.in does not resolve to address 203.199.213.14: Name or service not known
Mar 9 07:15:15 pmx01 postfix/smtpd[3930]: connect from unknown[203.199.213.14]
Mar 9 07:15:16 pmx01postfix/smtpd[3930]: Anonymous TLS connection established from unknown[203.199.213.14]: TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)
Mar 9 07:15:17 pmx01 postfix/smtpd[3930]: NOQUEUE: reject: RCPT from unknown[203.199.213.14]: 450 4.7.25 Client host rejected: cannot find your hostname, [203.199.213.14]; from=<sender1@iitm.ac.in> to=<receiver1@entity.hi.edu> proto=ESMTP helo=<mailx4.iitm.ac.in>
Mar 9 07:15:17 pmx01 postfix/smtpd[3930]: disconnect from unknown[203.199.213.14] ehlo=2 starttls=1 mail=1 rcpt=0/1 quit=1 commands=5/6
 
Try adding the IP to the mail proxy whitelist - the reject happens on the first postfix - and the mailproxy whitelist should prevent this.


helo or SPF on some domain,
That should be the mailproxy whitelist

What if I want to disable spam/virus checks for a specific receiver, I guess I have to create the mail filter rules for the specific receiver right? Thank you very much.
Yes that sounds correct!

I hope this helps!