Virtual Hosting DNS Question

[Jay Nugent]

Greetings,

On Mon, 23 Feb 2004, Chong Yu Meng wrote:

> 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.

   Put simply, you cannot use a CNAME to define your MX host or NS
servers.  Other than that, CNAMES are fine to use elsewhere.


demo.xyzdomain.com     IN   A       xxx.yyy.zzz.hhh
apps.xyzdomain.com     IN   CNAME   demo.xyzdomain.com.
www.xyzdomain.com      IN   CNAME   demo.xyzdomain.com.

   --- or ---

demo.xyzdomain.com     IN   A       xxx.yyy.zzz.hhh
apps.xyzdomain.com     IN   CNAME   xxx.yyy.zzz.hhh
www.xyzdomain.com      IN   CNAME   xxx.yyy.zzz.hhh

   Yes.  It is absolutely okay to point many hosts to the *same* IP 
address.

   Enjoy!
      --- Jay

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