Solved

Reverse PTR record on a shared box

Posted on 2007-04-04
5
221 Views
Last Modified: 2010-04-10
Hello,
  I have a dedicated hosting box with a hosting company.  People were complaining that they would try to send me an email and it would say user mailbox does not exist.  My hosting company said they need to create a reverse PTR record for me.  This seems to have fixed the problem for me but what about for my clients.  If someone tries to send an email to someone@AnotherDomainOnMyHost.com won't they need their own reverse PTR record since when they do a reverse dns lookup it will say mail.MyDomain.com?
0
Comment
Question by:rickBergami
  • 3
  • 2
5 Comments
 
LVL 70

Expert Comment

by:Chris Dent
ID: 18853682

Not exactly.

The Reverse Lookup Record is there as a quick check to point out unofficial mail servers.

When your server sends out mail it should do so as mail.yourdomain.com. That won't change when you're sending mail for a different domain it's part of the SMTP servers configuration.

All the PTR record has to do is match that single mail.yourdomain.com entry.

Hope that makes sense.

Chris
0
 

Author Comment

by:rickBergami
ID: 18853804
Thanks very much for your help.  So you are saying when one of my clients sends from mail.TheirDomain.com it just needs to be authenticated against mail.MyDomain.com (or mail.AnyDomain.com for that matter)?
0
 
LVL 70

Expert Comment

by:Chris Dent
ID: 18854019

If your server is sending their mail then it doesn't really matter much what domain they're sending from. Your server will send out as it's name, never anything else.

That still applies even if they access your mail server as mail.TheirDomain.com. It's not what they see, but what your server believes itself to be.

I hope that makes sense! :)

Chris
0
 

Author Comment

by:rickBergami
ID: 18854139
Thanks Chis.  This has been very insightful.  The reason this started is because I had a friend of my contact me that some people were unable to email them and got a message saying this user did not exist.  I thought it might be because they do not have a reverse PTR record on their server.  Their host is godaddy.  I would think that a big company like godaddy would have this set up?  I contacted them and they said they do not support this feature but wouldn't they have something set up like mail.godaddy.com?
0
 
LVL 70

Accepted Solution

by:
Chris Dent earned 500 total points
ID: 18854275

For e-mail sent to a user it's unlikely that reverse DNS is responsible. That's where the Recipients server (yours in this case) checks that the Sending server is telling the truth about it's name - it's not something that happens by default, you'd have to configure it.

For the User does not exist type messages you must try and reproduce the problem when sending mail into your server. Generally we'd do this using Telnet. MS have a little article on how to do that:

http://support.microsoft.com/kb/153119

If you've tested that you can indeed receive messages for that user you should do a quick check of the MX Records for that domain. If you go to www.dnsreport.com and put the domain in it will show you a report on the MX Record configuration as well as a lot of other information.

Check that any entries in the MX Record are able to receive mail for the address concerned.

Chris
0

Featured Post

Enabling OSINT in Activity Based Intelligence

Activity based intelligence (ABI) requires access to all available sources of data. Recorded Future allows analysts to observe structured data on the open, deep, and dark web.

Join & Write a Comment

Suggested Solutions

This is an article about my experiences with remote access to my clients (so that I may serve them) and eventually to my home office system via Radmin Remote Control. I have been using remote access for over 10 years and have been improving my metho…
ADCs have gained traction within the last decade, largely due to increased demand for legacy load balancing appliances to handle more advanced application delivery requirements and improve application performance.
Viewers will learn how to connect to a wireless network using the network security key. They will also learn how to access the IP address and DNS server for connections that must be done manually. After setting up a router, find the network security…
In this tutorial you'll learn about bandwidth monitoring with flows and packet sniffing with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're interested in additional methods for monitoring bandwidt…

759 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

20 Experts available now in Live!

Get 1:1 Help Now