We recently added an option for the display of a system policy file at the
SMTP greeting.
The logic is to first display the standard SMTP greeting line:
220-hostdomain [product info] Server Ready
followed by admin's system policy file (if found) as extra 220 response
lines. The last line, of course, does not contain the dash. For example:
220-winserver.com Wildcat! ESMTP Server v5.7.450.9b13 ready
220-************** WARNING: FOR AUTHORIZED USE ONLY! **********************
220-* THIS SYSTEM DO NOT AUTHORIZE THE USE OF ITS PROPRIETARY COMPUTERS *
220-* AND COMPUTER NETWORKS TO ACCEPT, TRANSMIT, OR DISTRIBUTE UNSOLICITED *
220-* BULK E-MAIL SENT FROM THE INTERNET. THIS SYSTEM WILL RESTRICT ACCESS *
220-* TO CAN-SPAM (US S. 877) COMPLIANT CLIENTS ONLY. *
220 ************************************************************************
We got a question from a customer saying DNSREPORT.COM
(http://www.dnsreport.com) is reporting a warning abort a host name
mismatch in the greeting. DNSREPORT.COM is a popular SMTP compliancy
testing site.
Checking it out for myself against my system, it reports:
WARNING: One or more of your mailservers may be claiming to be a
host other than what
it really is (the SMTP greeting should be a 3-digit code, followed
by a space or a dash, then the
host name). This probably won't cause any harm, but may be a
technical violation of RFC821 4.3.
mail.winserver.com claims to be host **************.
It seems DNSREPORT.COM is only looking at the last line to get the
information it expects.
I tested this theory by manually adding a simulated SMTP greeting line that
looks like the top line to the bottom of the system policy:
220-winserver.com Wildcat! ESMTP Server v5.7.450.9b13 ready
220-************** WARNING: FOR AUTHORIZED USE ONLY! **********************
220-* THIS SYSTEM DO NOT AUTHORIZE THE USE OF ITS PROPRIETARY COMPUTERS *
220-* AND COMPUTER NETWORKS TO ACCEPT, TRANSMIT, OR DISTRIBUTE UNSOLICITED *
220-* BULK E-MAIL SENT FROM THE INTERNET. THIS SYSTEM WILL RESTRICT ACCESS *
220-* TO CAN-SPAM (US S. 877) COMPLIANT CLIENTS ONLY. *
220-************************************************************************
220 winserver.com Wildcat! ESMTP Server v5.7.450.9b13 ready
and this time it got pass this particular SMTP greeting/hostname test.
The question I have is what is the correct logic?
Where should the offical SMTP greeting line be in a multi-line greeting
display? Top or Bottom? Both maybe for compatibility? Unless I missed
it, RFC 2821 does not touch on this particular subject item.
Thanks in advance
--
Hector Santos, Santronics Software, Inc.
http://www.santronics.com