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I am seeing a lot of email bouncing from my server... the bounce messages indicate that the IP does not have reverse DNS set up, but I can see valid rDNS records when I query it on my local machine. I know I set the rDNS records at least four days ago, so I am sure any TTLs would have expired. What could be causing this and how can I troubleshoot?

The server's IP is:

Here is a sample bounce message, with email addresses removed:
  SMTP error from remote mail server after initial connection:
  host []:
  554 5.7.1 - Connection refused. IP name lookup failed for

------ This is a copy of the message, including all the headers. ------
------ The body of the message is 3307201 characters long; only the first
------ 106496 or so are included here.

Received: from ([])
      by with esmtpsa (TLSv1:RC4-SHA:128)
      (Exim 4.69)
      (envelope-from )
      id 1Q1dLe-0004yE-VA
      for; Mon, 21 Mar 2011 07:32:36 -0400
Received: by pxi15 with SMTP id 15so1073240pxi.5
      for ; Mon, 21 Mar 2011 04:32:36 -0700 (PDT)
MIME-Version: 1.0
Received: by with SMTP id x5mr2803872wfh.440.
1300707156399; Mon,
21 Mar 2011 04:32:36 -0700 (PDT)
Received: by with HTTP; Mon, 21 Mar 2011 04:32:36 -0700 (PDT)
Date: Mon, 21 Mar 2011 07:32:36 -0400
Subject: invoice for reprint/final proof
From: aaaa bbbbbb 
Content-Type: multipart/mixed; boundary=001636ed678203ac8b049efc7ca1

Sent from my iPad
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It would help to see the contents of the SMTP transaction between your mail server and the rejecting mail server. – chuckx Mar 21 '11 at 16:16

Your PTR address works. If it didn't, RR would return a 421 error instead of a 554. Your DNS seems fine to me (Report here)

I believe that the 554 error means that your email server needs to correctly identify itself as the hostname in question ( when connecting. For example, it should greet the RR server with "EHLO"

More info here:

share|improve this answer
I just had this same issue, and fixed it by matching my mail server banner with the PTR record - as hyppy describes. – charnley Mar 21 '11 at 16:06
This seems like a very likely cause, but I believe my mail server is identifying itself as I'll view a tcpdump to be sure. – Josh Mar 21 '11 at 17:12

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