how to resolve the problem of reverse DNS
 

Hi all,

I have the following problems when our colleagues try to send out emails to their receiptents. It is also reported from the reciptent that there's a reverse DNS problem, is it our email server needed to be configured with some settings ? Please give me a hand steps by steps as I really new with the server configuration. Now I just change /etc/mail/access and use our ISP provided SMTP for the solution, but it seems not ok.

Thanks
Keith


Problem 1
=====================================
----- Original Message -----
From: "Mail Delivery Subsystem"
To: <xxxx@ivisions.biz>
Sent: Tuesday, September 05, 2006 10:40 AM
Subject: Returned mail: see transcript for details



>> The original message was received at Tue, 5 Sep 2006 10:40:32 +0800
>> from [218.18.189.99]
>>
>> ----- The following addresses had permanent fatal errors -----
>> <xxxxx@cantv.net>
>> (reason: 550 5.7.1 <xxxxx@cantv.net>... 202.155.234.91 does not have

a matching IN PTR Resource Record - See/Vea
http://abuso.cantv.net/faqs/mail-dns)

>>
>> ----- Transcript of session follows -----
>> ... while talking to relay.cantv.net.:
>
>>>>> >>> DATA
>
>> <<< 550 5.7.1 <xxxxx@cantv.net>... 202.155.234.91 does not have a

matching IN PTR Resource Record - See/Vea
http://abuso.cantv.net/faqs/mail-dns

>> 550 5.1.1 <xxxxx@cantv.net>... User unknown
>> <<< 503 5.0.0 Need RCPT (recipient)

Problem 2
=====================================


**********************************************
** THIS IS A WARNING MESSAGE ONLY **
** YOU DO NOT NEED TO RESEND YOUR MESSAGE **
**********************************************



----- Transcript of session follows -----
... while talking to mailin-01.mx.aol.com.:

>>>>>> DATA

<<< 421-: (DNS:NR) http://postmaster.info.aol.com/errors/421dnsnr.html
<<< 421 SERVICE NOT AVAILABLE
... while talking to mailin-02.mx.aol.com.:

>>>>>> DATA

<<< 421-: (DNS:NR) http://postmaster.info.aol.com/errors/421dnsnr.html
<<< 421 SERVICE NOT AVAILABLE
... while talking to mailin-03.mx.aol.com.:

>>>>>> DATA

<<< 421-: (DNS:NR) http://postmaster.info.aol.com/errors/421dnsnr.html
<<< 421 SERVICE NOT AVAILABLE
... while talking to mailin-04.mx.aol.com.:

>>>>>> DATA

<<< 421-: (DNS:NR) http://postmaster.info.aol.com/errors/421dnsnr.html
<<< 421 SERVICE NOT AVAILABLE
<Gloryinter@aol.com>... Deferred: 421-: (DNS:NR) http://postmaster.info.aol.com/errors/421dnsnr.html
Warning: message still undelivered after 4 hours
Will keep trying until message is 5 days old



Reporting-MTA: dns; venus.isofts.biz
Arrival-Date: Thu, 29 Jun 2006 15:07:41 +0800

Final-Recipient: RFC822; xxxxx@aol.com
Action: delayed
Status: 4.0.0
Remote-MTA: DNS; mailin-04.mx.aol.com
Diagnostic-Code: SMTP; 221 SERVICE CLOSING CHANNEL
Last-Attempt-Date: Thu, 29 Jun 2006 19:19:17 +0800
Will-Retry-Until: Tue, 4 Jul 2006 15:07:41 +0800

Doesn't look like a problem of your server but rather of how you're
operating on the big stage. The mail-servers public IP address doesn't
resolve to a name (for these people, at least) and that makes them
unhappy to such extent that they refuse mail from your machine. To
fix that have a nice word to whoever is your internet service provider.
(Or, if you're running this of a home-network type of thing, get a
free DNS provider to point a name to your IP).



Cheers,
Tink