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lehadi 9th May 2006 14:27

Postfix smtpd_banner
I have a probleme with my POSTFIX server installed in Redhat Entrprise Linux 3.
The Postfix server is in DMZ protected by a PIX515E. It is NATed from private IP adress to a public IP adresse by the PIX. The recpetion and send a message is working. But, the probleme is the greeting message of POSTFIX. When I do a test from the LAN (Inside) with TELNET in port 25, the greeting message configured in postfix whith de smtpd_banner parametre in chown correctely :
220 - ESMTP Postfix

When I do a test from Internet the greetin message is :
220 - *********************



falko 9th May 2006 17:59

Do you forward port 25 from your router to the correct mail server? Maybe another mail server from your LAN is answering when you try to connect from the internet.

lehadi 9th May 2006 18:41

Send and recpetion of mail is working
Hello falko,
the send and recpetion of mail is working, my probleme is just de greeting message. In the PIX, I permit connexion from internet to my SMTP server and my SMTP server go to Internet to send message.


falko 10th May 2006 00:06

Yes, but did you forward port 25 from your router to the correct mail server?

lehadi 14th May 2006 11:07

Permission ACCESS-LIST
the command ACCESS-LIST in the CISCO-PIX515E allow (permit) a connexion from Internet to my mailserver. I receive mail from internet (yahoo, gmail,etc) and I can send e-mail to Internet. So the transmission of email throw the SMTP port is correct.


falko 14th May 2006 17:06

And you are absolutely sure you forward port 25 to the correct mail server in your LAN? How many mail servers do you have in your LAN?
What's in /etc/postfix/
Can you tell me your real domain?

lehadi 15th May 2006 16:41

Solved !

The probleme was in the PIX515E. The PIX are doing a filtring in th application level. (The command wich cause the probleme is: fixup protocol smtp 25). So, certainly it bloque the HELO message of SMTP protocol.


lehadi 15th May 2006 18:14

Some lines CISCO-PIX manual

Some lines from CISCO-PIX515E wich explain the fixup command :
" ....
The fixup protocol smtp command enables the Mail Guard feature. This restricts mail servers to receiving the seven minimal commands defined in RFC 821, section 4.5.1 (HELO, MAIL, RCPT, DATA, RSET, NOOP, and QUIT). All other commands are rejected.
As of version 5.1 and higher, the fixup protocol smtp command changes the characters in the server SMTP banner to asterisks except for the "2", "0", "0" characters.

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