Virtual Hosting DNS Question

[Chong Yu Meng]

Hi All,

I need to install and configure a server for virtual hosting. Because of 
a shortage of IP addresses, I need to use name-based virtual hosting. 
Now, for Apache, this is easily done, but I don't know how to add the 
records for the DNS. My scenario is as follows:

The server will have 3 virtual hosts sharing 1 IP address:

demo.xyzdomain.com
apps.xyzdomain.com
www.xyzdomain.com

What entries must I make into the DNS ? I understand that you can use 
CNAME, but that practice is discouraged -- I don't know why, though.

Any help would be greatly appreciated !

Regards,
pascal chong