?
Solved

Difference between A record and Subdomain

Posted on 2012-12-26
3
Medium Priority
?
1,216 Views
Last Modified: 2012-12-26
So, I'm curious about the difference between a subdomain and an A record in DNS. I've never had any issues, but I'm curious about how/why "A record" and "Subdomain" seem to be interchangeable for some people.

For example,

example.com (domain)

www.example.com (www is an "A" record within example.com)

server.america.example.com (server is an "A" record within the subdomain of "america.example.com).

This makes sense to me. However, I'm finding some people who argue that in the example "www.example.com", that www is actually a subdomain and not an A record.

Is there actually a difference between the two or is the difference simply in implementation?

Thanks,
Tim
0
Comment
Question by:timmr72
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
3 Comments
 
LVL 27

Assisted Solution

by:davorin
davorin earned 500 total points
ID: 38721827
A record defines FQDN (full qualified domain name) of the host which belongs to a certain domain.
Subdomain does not define a single host (or computer/server). Hosts do part of (sub)domain.
(Sub)domain is just administrative entity.
0
 
LVL 40

Accepted Solution

by:
footech earned 500 total points
ID: 38722278
I don't think there's much to add to the answer, but sometimes restating info in a different way helps understanding.
When you get right down to it, an A record is a specific type of DNS record.  It references a FQDN to an IP.  CNAME records also reference FQDNs, and so do some others.  I think I've actually seen a web host/registrar (might have been 1and1) that when you were creating a record inside a domain it prompted you to specify the subdomain.  IMO, "subdomain" can be used informally in a few scenarios, but it doesn't seem to have a specific definition.  I'd call it more a term for an administrative unit than anything else.  A child domain (which you could also call a subdomain), is a domain in its own right, so denver.co.us.americas.gov could either refer to a (sub)domain or to a specific host - until you add some context to it it isn't clear and probably doesn't matter.
0
 

Author Closing Comment

by:timmr72
ID: 38722290
Thank you both.
0

Featured Post

Free Backup Tool for VMware and Hyper-V

Restore full virtual machine or individual guest files from 19 common file systems directly from the backup file. Schedule VM backups with PowerShell scripts. Set desired time, lean back and let the script to notify you via email upon completion.  

Question has a verified solution.

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

There have been a lot of times when we have seen the need to enter a large number of DNS entries in a forward lookup zone. The standard procedure would be to launch the DNS Manager console, create the Zone and start adding new hosts using the New…
Resolve DNS query failed errors for Exchange
If you’ve ever visited a web page and noticed a cool font that you really liked the look of, but couldn’t figure out which font it was so that you could use it for your own work, then this video is for you! In this Micro Tutorial, you'll learn yo…
Have you created a query with information for a calendar? ... and then, abra-cadabra, the calendar is done?! I am going to show you how to make that happen. Visualize your data!  ... really see it To use the code to create a calendar from a q…

752 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