About subdomains

Subdomains are lower-level domains hosted on a registered root domain. If subdomains are enabled for your site, you can add subdomains to name-based as well as IP-based domains.

For example, if you own the root domain name yourdomain.com, WEBppliance enables you to create subdomains such as sales.yourdomain.com. You do not need to register the subdomain sales.yourdomain.com, since it is based on your registered root domain name. Users can access it, however, by typing the subdomain URL in a browser just as they do yourdomain.com.
 

Subdomains 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.

Apart from creating subdomains for a site, you can also create subdomains for users when you add a user to the site. In this case, the subdomain assumes the name of the user.
For example, if you are adding a user, Bob, to your site, mysite.com, then a subdomain 'bob' will be created. The subdomain can be accessed as http://bob.mysite.com.

Advantages of subdomains

Subdomains offer the following advantages:

1. Reinforce branding and Web presence

Subdomains 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 of service.

2. Simplify 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.

3. Independent 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.

The subdomain environment

Subdomains, at the file system level, are simply subfolders that contain the requisite Web content for the subdomain. All subdomains for the site are, by default, placed in the /var/www directory. For user subdomains, the subdomain directory (where content for the subdomain is uploaded) defaults to the public_html directory of the user, /home/<user name>/public_html/ where <user name> is the name of the user for which the subdomain is created.

You can enable a subdomain with the following capabilities:

• Aliases

• CGI Support

• CGI script aliases

Aliases

Aliases are nicknames or alternative Web addresses that map to an existing subdomain. They are alternative access URLs that point to your subdomain. Subdomains inherit alias definitions from the parent domain.

For example, if the parent domain, www.yourdomain.com, with the associated alias, www.yourdomain.org, has a subdomain, http://sales.yourdomain.com, then if enabled to inherit aliases, this subdomain can also be accessed using the alias, http://sales.yourdomain.org.

CGI support

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 a repository called the CGI-BIN directory. The CGI-BIN directory, by default, resides as a folder outside the subdomain folder, /cgi-bin/, or can be relocated (aliased)  to a special directory located in the protective environment of the parent file system, /usr/web/cgi-bin/.  

CGI scriptaliases

CGI scriptaliases allow you to run CGI scripts from within the protected environment of the local file system of the domain. A scriptalias is a feature that enables you to secure the integrity of script resources from other hosts on the server.

For example, if the cgi scripts for a subdomain are aliased or relocated to /usr/web/cgi-bin/, instead of the default /cgi-bin/, then a request for http://myscript/cgi-bin/search will run the script from /usr/web/cgi-bin/search instead of /cgi-bin/search.

As a Site Administrator, you can:

• Create subdomains for a registered domain

• View current subdomain details

• Change subdomain configuration

• Set subdomain defaults

• Delete subdomains

Before creating a subdomain

Before creating a subdomain, have the following information ready.

• Note: You can create subdomains for a site only if your site has been enabled to host subdomains by your service provider. The number of subdomains you can create is set by your service provider at the time of creating your site.

• Name of the subdomain - Choose a name for your subdomain.
  For example, if you have a root domain, www.yourdomain.com, then the URL of your subdomain, say sales, will be http://sales.yourdomain.com.

• Full directory path of the subdomain - The absolute path to the subdomain directory where all the required content resources for the subdomain will be located.

• Important: The directory path must be specified as an absolute path. For example, you must specify /var/<mysubdomain> not <mysubdomain>, where mysubdomain is the name of your subdomain directory.