2009/12/28

wildcard domains

I have tried configuring wildcard domains for Bind and Apache to work together. In Bind, the syntax of a zone file (example.com) is simple :

*.example.com. 1H IN A 1.2.3.4

As for Apache, the directive for supporting named-based virtual hosting must be enabled:

NameVirtualHost 1.2.3.4

Next comes the ServerAlias to align with the virtualhost:

# comment: this one accepts any subdomain
#
< VirtualHost 1.2.3.4:80>
DocumentRoot /var/www/html/subdomain
ServerName www.example.com
ServerAlias *.example.com
< /virtualhost>

The above configuration is easily understood. Any URL ending with example.com will access www.example.com. The sequence of wildcard entry is worthy of precaution. The wildcard entry must be the last and must come after valid subdomain name because Apache looks at lines and files and uses the first one that has matched.

I can not think of any practical applications of wildcard domains. Some might argue that if the subdomain part is mistyped, users can still reach the correct website.

One question I have in mind is can IIS support wildcard domains?

No comments: