Solved

reverse DNS question

Posted on 2008-10-21
2
220 Views
Last Modified: 2010-04-07
I have installed a Barracuda spam firewall to filter all of my *outbound* email from my mail server.  Because of this, I now have a DNS question.

The public ip address of my email server is 12.34.56.1 and that is associoated with mail.mydomain.com

All outbound email goes from the mail server first to the Barracuda & then out to the internet.  When the Barracuda sends out the mail, the email is identified as coming from 12.34.56.2

Some email messages have been rejected because some recipient's servers attempt a reverse dns lookup on 12.34.56.2 & there is no reverse dns  lookup for that ip.
 
I'm guessing a solution would be to add a "reverse DNS" entry for 12.34.56.2 - mail.mydomain.com

However, I'm worried - I don't want any mail to be sent back to 12.34.56.2 since that is an outbound device only.  I want mail to only come in on 12.34.56.1

Is adding this reverse DNS entry safe?
0
Comment
Question by:brianp111
  • 2
2 Comments
 
LVL 2

Expert Comment

by:MobiNet-ca
ID: 22767215

I would create a reverse DNS record such as "outbound.mydomain.com" and point it at 12.34.56.1 and leave the records for the real mail server alone.
0
 
LVL 2

Accepted Solution

by:
MobiNet-ca earned 500 total points
ID: 22767223
Sorry that should have been the .2 IP

I would create a reverse DNS record such as "outbound.mydomain.com" and point it at 12.34.56.2 and leave the records for the real mail server alone.
0

Featured Post

How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

Join & Write a Comment

This article explains how a domain name may be inadvertently appended to all DNS queries. This exhibits as described below. (CODE)And / Or: (CODE) Cause This issue can occur in either of these two scenarios. EITHER 1. A Primary DNS S…
One of the most often confused topics in the area DNS is the idea of GLUE records. Specifically, what they are, when they are needed, when they are provided, and how they are created. First, WHAT IS GLUE? To understand GLUE, you must first under…
This tutorial demonstrates a quick way of adding group price to multiple Magento products.
You have products, that come in variants and want to set different prices for them? Watch this micro tutorial that describes how to configure prices for Magento super attributes. Assigning simple products to configurable: We assigned simple products…

746 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

10 Experts available now in Live!

Get 1:1 Help Now