CBL This IP address is HELO’ing as “localhost.localdomain”


I am pretty lost here, my server somehow got into a blacklist. And I don't know why and how to solve it. Please take a look at the link below.

CBL List – click here

Anyone knows what is going on here? I am not spamming mails, I am just hosting a forum.

I will provide any information needed, just reply.


EDIT: I have gotten this email.

This is the mail system at host

I'm sorry to have to inform you that
your message could not be delivered to
one or more recipients. It's attached

For further assistance, please send
mail to postmaster.

If you do so, please include this
problem report. You can delete your
own text from the attached returned

              The mail system

<********@atlantmail.com>: host
said: 550 5.7.1
: Helo command
rejected: Host not found (in reply to
RCPT TO command)

Final-Recipient: rfc822;
*******@atlantmail.com Action:
failed Status: 5.7.1 Remote-MTA: dns;
Diagnostic-Code: smtp; 550 5.7.1
: Helo command
rejected: Host not found


My postfix settning:

myhostname = yo.atlava.com alias_maps
= hash:/etc/aliases alias_database = hash:/etc/aliases myorigin =
/etc/mailname mydestination =
atlava.com, yo.atlava.com,
localhost.atlava.com, localhost

(none):~# hostname -f
hostname: Unknown host

Best Answer

As the page states, the HELO is not why your server is listed.

IP Address is listed in the CBL. It appears to be infected with a spam sending trojan or proxy.

is why your server is listed. You'll need to figure out why it's being flagged as such and correct it.

Changing how your server identifies itself in the HELO is specific to the SMTP server that you're running. Can you give us a clue?


Ok, got it. You have a couple of problems based on your edit:

  1. CBL thinks you're spamming but offers no details on what exactly they're flagging you on.

  2. It looks like atlantamail.com is rejecting your email because it can't validate the name your SMTP server is giving in the HELO command. You'll need to figure out where in Postfix to set the outgoing FQDN in the HELO and set it to something legitimate, such as hostname.mypublicdomain.com. If you send and receive email on the same server then it's easiest to set the FQDN to match your MX record and then you can create an SPF record that authorizes your MX to send email for your domain. None of these will guaranteee that your email will be accepted but will help.