are lower-level domains hosted on a registered root domain.
For example, if you own the root domain name example.com,
you can host a subdomain, sales,
on your root domain. Users can access the subdomain, by typing the subdomain
URL, sales.example.com, in a
browser just as they do example.com.
You do not need to register the subdomain, since it is based on your registered
root domain name.
3rd level domain
2nd level domain
Top-level domain or 1st level domain
enable you to organize and position Web data and services into distinct
online channels. Supporting business units, separate product lines and
diverse geographies of enterprises can be effectively web-managed as subdomains.
To create subdomains, your service provider must enable subdomains for
your site. You can add subdomains to name-based as well as IP-based sites.
The number of subdomains
you can create is also set by your service provider at the time of creating
Advantages of subdomains
offer the following advantages:
branding and Web presence
enable you to create distinct online service channels for affiliated business
data and services while preserving brand association. This reinforces
brand value and extends your Web presence through alternative channels
management of large domains
Large domains can be split up into separate logical
entities in alignment with your organizational setup and web-managed separately.
Thus, your enterprise can have a separate yet affiliated Web presence
for sales, support, human resources, and other business divisions apart
from your primary Web site.
private online repository of content
Each subdomain has its own private repository of online
content resources. The subdomain folder contains all the content resources
necessary for the subdomain to be accessible from a Web browser. This
segregation averts content or resource violation and ensures secure management
of subdomain content.
at the file system level, are simply subfolders that contain the requisite
Web content for the subdomain.
You can create two types of subdomains:
Regular subdomains can be created using the Add
subdomain option. Regular subdomains can be located anywhere in the
site's file system within the subdomain base
All the regular subdomains for the site are, by default,
placed in the /var/www
directory, also called the base directory. Your service provider sets
the base directory.
For example, if /var/www
is the base directory set by your service provider and you create a subdomain,
then your subdomain will be located at /var/www/mysubdomain
User subdomains can be created using the Add
User option. A user subdomain is a subdomain that has the same name
as its owner. The subdomain will, by default, be located in the home directory
of the user under the public_html
folder. The subdomain directory cannot be changed by the user.
For example, if you enable a user subdomain for the
then the user subdomain will be called myname
and will be located at /home/myname/public_html/
Subdomains inherit the security
level and aliases defined for the root domain.
The security level inherited by the subdomain will determine the operating
environment of the subdomain. You can enable CGI
Support for subdomains to enable users to run CGI scripts.
Aliases are nicknames or alternative web addresses that map
to an existing subdomain. Subdomains inherit the aliases configured for
the root domain. To determine if aliases are available for the subdomain,
see the URL field in the Subdomains
Details form. You will find the subdomain URL along with the list
of aliases (if the root domain has aliases).
You can access subdomains using aliases only if the root domain has aliases
If your root domain, example.com,
is configured to be accessible using the alias, example.net,
then the subdomain, sales,
hosted on the root domain can also be accessed using the alias, sales.example.net.
CGI scripts enable you to capture and process information
dynamically. They can be used to retrieve information from a database,
collect Web statistics and perform searches.
CGI scripts are placed in the cgi-bin directory under the
subdomain folder. Hence, if the subdomain, sales,
is located within the /var/www/sales/
directory, then the CGI scripts for the subdomain will be placed in the
directory in the root domain's file system.
To run a subdomain CGI script, in the Address field of your
Web browser, type the following:
<subdomain_name> is the name of your subdomain
<domain_name> is the domain name of the site on which your
subdomain is hosted
<script_name> is the name of the cgi script
As a Site Administrator, you can:
for a registered domain
current subdomain details
default subdomain settings
Before creating a subdomain, have the following information
of the subdomain - Choose a name for your subdomain.
directory path of the subdomain - The name of the directory where
all the required content resources for the subdomain will be located.
Site Administrator's Help
Published April 16, 2004