How to create a subdomain

Think of it as a subordinate space of your domain.

Let's say that you have a simple website with Gandi's Simple Hosting service, and publish it at http://www.example.com. In this case, your site is hosted on the www subdomain.

But what if you want to have a blog too? One that does not interfere with the website? Easy: simply set up your blog on a different subdomain, such as blog. Visitors can then access your blog at http://blog.example.com and your website still at http://www.example.com.

Do you want to publish your photo album that you made with Sitemaker too? No problem: put it on another subdomain, such as photos. Your album will be visible at http://photos.example.com, and your other sites will not be affected in the slightest.

Anything else? Perhaps a wiki that you host on a VPS? Again, just add another subdomain….

The first thing that you need to to is to add a line in your DNS zone file.

The purpose of this zone file entry is to tell the name servers:

1. that a subdomain exists, and
2. where to find the website associated with that subdomain.

Let's say you want to “point” www.example.com to a Gandi Simple Hosting server. To do this, you'll need to add an entry in your DNS zone file similar to this one ¹⁾:

www 10800 IN CNAME gpaas1.dc0.gandi.net.

(Don't forget the dot at the end of the CNAME entry or it will not work!!!)

And perhaps you have a mobile phone website hosted by Wix and you need a ”m” subdomain, then you just add a line like:

m 10800 IN A 216.139.213.144 

etc.

Your host will tell you whether or not you need to add an IP address or a subdomain. If it is an IP address that you need to use, then you'll create an A record. If you are given a domain name (like web.me.com, ghs.google.com, etc.) then you need to make a CNAME record.

The changes to the zone file can only be done with the company that manages your DNS.

• If you are using Gandi's DNS, you can see how to add your CNAME or A records in order to create your subdomain at the below pages:
  • How to add or change an A record
  • How to add or change a CNAME record

Allow around 3 hours for changes to your zone file to propagate across the internet.

• The www subdomain