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Bug with SMTP banner - urgent

FirstPoint

Basic Pleskian
Hello,

Sorry for mentionning "urgent" in the topic title, but it actually is, since we are progressively migrating domains from one server to the new one.

On the new one, we configured Plesk to use the IP of the domain for SMTP, aswell as SMTP banner.

This seems correct when we check master.cf. For each domain, we have one line like this:

domain.tld-IP.IP.IP.IP- unix - n n - - smtp -o smtp_bind_address=IP.IP.IP.IP -o smtp_bind_address6= -o smtp_address_preference=ipv4 -o smtp_helo_name=DOMAIN
Expected result would be that when we telnet to the IP of the domain, we get an SMTP banner with the related domain. But this does not work. We always get the FQDN of the server.

This is a serious problem as it is causing mail listed as spam at various providers. Please can you tell us how to resolve this ? Thanks.
 
Did you set the rDNS of the IP address to the respective domain name? Do this as the first step to resolving the SPAM problem.
 
Hello. Yes each rDNS is set to the respective domain. But the SMTP banner doesn't answer with the domain name, but with the main FQDN of the server
 
Hello. On plesk 12 this feature is actually covered. But it doesn't work as expected.

Here is an example.
Plesk on our server (FQDN = server.tld), is configured to send e-mails with the domain's IP address and the domain name in the SMTP banner.
domain1.tld is hosted on 123.456.78.9
user@doman1.tld sends an e-mail to test@gmail.com
In the header of the e-mail (checked within gmail), here is the result:
Received: from webmail.domain1.tld (localhost.localdomain [127.0.0.1])
by server.tld (Postfix) with ESMTPSA id 2BABA216076D
for <test@gmail.com>; Thu, 5 Feb 2015 20:09:13 +0100 (CET)

We would expect having domain1.tld in the banner.

Also, when I telnet to the IP 123.456.78.9, either on port 25 or 587, the server replies:
220 server.tld ESMTP Postfix
Here we would expect having the domain name, no ?

In /etc/postfix/main.cf, I see that Plesk however generated one of these lines for each domain
plesk-domain1.tld-123.456.78.9- unix - n n - - smtp -o smtp_bind_address=123.456.78.9 -o smtp_bind_address6= -o smtp_address_preference=ipv4 -o smtp_helo_name=domain1.tld
But it doesn't seem to use it.

We would really appreciate any help. Thanks !
 
Also, when I telnet to the IP 123.456.78.9, either on port 25 or 587, the server replies:
220 server.tld ESMTP Postfix
Here we would expect having the domain name, no ?
No.
You are talking of two different things.
It's Server SMTP Banner and it has nothing to deal with how Plesk configured to send outgoing mails.
Do not mix SMTP greeting and SMTP banner.
 
http://download1.parallels.com/Ples...inistrator-guide/index.htm?fileName=59430.htm
  1. In Plesk for Linux with the Postfix mail server, you can change the IP address used for sending mail. Also, if your server sends mail from domain IP addresses, you can specify which name will be used as the host name in SMTP greetings.
    Choose from the three options:
    • Send from domain IP addresses. By default, mail from each domain is sent using the domain's IP address. The host name used in the SMTP greeting is defined by the configuration of the mail server.
    • Send from domain IP addresses and use domain names in SMTP greeting. If selected, Plesk changes the mail server configuration so that the SMTP greeting will contain the name of the domain from which an email message is sent.
      This option helps to prevent the sender's IP address from being added to public black lists, such as the Spamhaus or OpenBL lists. This might happen if the mail server host name is used in the SMTP greeting for the messages sent from domain IP addresses. Some recipient servers consider such messages as spam.

      We recommend that you use this option if you host less than 100 domains. If there are a large number of domains, using this option significantly increases the load on the server.

    • Send from the specified IP address. You might want to use certain IPv4 and IPv6 addresses for all outgoing mail. Sending all mail from the specified address might be useful, for example, if the IP address of the mail server was added to a public black list, such as the Spamhaus or OpenBL lists. If you select None, outgoing mail will not be sent.
 
In our Plesk version, in french, it says "et utiliser les noms de domaines dans la bannière SMTP", which means "and use the domain name in the SMTP banner"... What am I mixing ?

And I don't see where you're trying to lead the conversation ? Since except dicussing my wording, you still can't explain why the SMTP banner, hostname, or HELO don't display the correct domain ?
 
In our Plesk version, in french, it says "et utiliser les noms de domaines dans la bannière SMTP", which means "and use the domain name in the SMTP banner"... What am I mixing ?

And I don't see where you're trying to lead the conversation ? Since except dicussing my wording, you still can't explain why the SMTP banner, hostname, or HELO don't display the correct domain ?

Hm... than that's serious mistake in french locale. It definitely should be reported to Plesk team.
Originally, plesk mailserver screen have no option to manage SMTP banner, but you can manage there SMTP greeting which plesk mailserver will use as a HELO with connection to destination server.
 
Anyways... why the HELO doesn't work correctly then ?

Received: from webmail.domain1.tld (localhost.localdomain [127.0.0.1])
by server.tld (Postfix) with ESMTPSA id 2BABA216076D
for <test@gmail.com>; Thu, 5 Feb 2015 20:09:13 +0100 (CET)

This "Received" section describes the path of your letter from webmail to plesk mailserver (postfix). i.e.:
your postfix mailserver received this letter from your webmail.
So, why do you think Plesk mailserver helo does not work properly?
Check "Received" on plesk->gmail stage. there you should see correct IP address and HELO with the domain name.
 
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