[CentOS] www.mydomain.org and mydomain.org should resolve to the same IP

On 07/31/2011 05:07 AM, Always Learning wrote:
>
> On Sat, 2011-07-30 at 19:39 -0700, John R Pierce wrote:
>
>> On 07/30/11 6:42 PM, Always Learning wrote:
>>> You can amalgamate that into a single entry .....
>>
>> that doesn't do the redirect.  I *want* it so that if you go to any of
>> these URLs...
>>
>>       http://astro.santa-cruz.ca.us
>>       http://www.astro.santa-cruz.ca.us
>>       http://www.astronomy.santa-cruz.ca.us
>>
>> you get redirected to
>>       http://astronomy.santa-cruz.ca.us
>>
>> try it, you'll see how that works.
>
>
> Instead of being 'redirected' why not go straight to the required web
> site http://astronomy.santa-cruz.ca.us whatever you enter:-
>
>          http://astro.santa-cruz.ca.us
>          http://www.astro.santa-cruz.ca.us
>          http://www.astronomy.santa-cruz.ca.us
>          http://astronomy.santa-cruz.ca.us
>
>
> ?
>
> Why make two moves when one is sufficient ?

Because once people link to the site or bookmark it using all four domains 
you essentially have to maintain all four domains for the rest of the live 
of the site i.e. through redesigns, restructurings, moves, etc.

The better approach is to declare one domain as canonical and redirect all 
other domains to it.

Also Google can reduce your page rank if it find the same content under 
multiple domains because it thinks you are cheating. Nowadays Google is 
supposed to be smart about this and doesn't count www.* vs non-www.* as 
duplicate content but the exact rules how Google determines this are not known.

Regards,
   Dennis