Want to protect your cyber security and still get fast solutions? Ask a secure question today.Go Premium

x
?
Solved

Reverse DNS

Posted on 2007-08-01
6
Medium Priority
?
469 Views
Last Modified: 2008-02-01
Can you explain reverse DNS to me?
0
Comment
Question by:cpqt
5 Comments
 
LVL 28

Accepted Solution

by:
peakpeak earned 100 total points
ID: 19610067
Normal DNS lookup translates a domain name like hotmail.com to an IP address (1.2.3.4)
Reverse DNS does just the opposite, translates the IP address to the domain name (1.2.3.4 -> hotmail.com)
Not that widely used but many email servers are set up to do a reverse DNS lookup to check that the sending domain indeed has the IP address it claims.
Not all domain names have a corresponding reverse DNS record
0
 
LVL 3

Assisted Solution

by:fetch_
fetch_ earned 100 total points
ID: 19610089
RDNS is just like what it sounds-  a DNS entry points a name (www.experts-exchange.com) to an IP address, well a reverse will say that 64.156.132.140 points to www.expers-exchange.com.  It's often use to verify mail is from who it says it's from on the message header.  

see also: http://www.webopedia.com/TERM/R/rDNS.html
http://www.crucialp.com/resources/tutorials/web-hosting/how-reverse-dns-works-rdns.php
0
 

Expert Comment

by:LibbyJax
ID: 19610093
Reverse DNS allows you to provide an IP address and determine which hostnames are attached to that IP.  The zone file is typically in the format of 1.168.192.in-addr.arpa.  The 1.168.192 is the address in reverse of the subnet that you are using Reverse DNS for.

A typical entry would look like:
192.168.1.10     PTR     somehostname

If you reverse DNS lookup on 192.168.1.10 it will return somehostname.
0
 
LVL 3

Expert Comment

by:fetch_
ID: 19611584
We all agree then.
0
 
LVL 1

Expert Comment

by:Computer101
ID: 20075454
Forced accept.

Computer101
EE Admin
0

Featured Post

Concerto's Cloud Advisory Services

Want to avoid the missteps to gaining all the benefits of the cloud? Learn more about the different assessment options from our Cloud Advisory team.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article is intended as an extension of a blog on Aging and Scavenging by the MS Enterprise Networking Team. In brief, Scavenging is used as follows: Each record in a zone which has been dynamically registered with an MS DNS Server will have…
Occasionally you run into the website or two that will not resolve properly using your own DNS servers.  Some people simply set up global forwarders for their DNS server.  I don’t recommend doing this because it can cause problems resolving addresse…
When cloud platforms entered the scene, users and companies jumped on board to take advantage of the many benefits, like the ability to work and connect with company information from various locations. What many didn't foresee was the increased risk…
How can you see what you are working on when you want to see it while you to save a copy? Add a "Save As" icon to the Quick Access Toolbar, or QAT. That way, when you save a copy of a query, form, report, or other object you are modifying, you…
Suggested Courses

576 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