Subdomain gets different IP

[turnon]

How good or bad is it for google (my most important friend on the internet , but i like you too guys) if the subdomain gets a total different IP adress

lets say main domian start with 213.xx.xxx and subdomain starts with 83.xx.xxxx

Thanx in advance

[DanDeceuster]

Ask yourself why you are using a domain and if you can accomplish the exact same thing by simply making a subdirectory. If you can, drop the subdomain. Always use subdirectories.

Google treats sub domains as separate websites, so having a different IP address doesn't matter, just makes it more separate I guess. That's why I wouldn't bother. Why separate your content?

[Tompt]

Whilst I do agree with Daniel Deceuster, subfolders are historically much nicer than subdomains. You're not going to get in trouble for having one on a different IP address. We use a subdomain for our members section (decision was made before my time), customers like that mental partition, and it's not done us any harm.

[turnon]

We like to use it for a Qand A section as descripted in

http://www.seomoz.org/blog/6-reasons-why-qa-sites-can-boost-your-seo-in-2011-despite-googles-farmer-update-12160

A main reason is also technical we run a magento website and the domain is a folder in the magento installation and for qanda i like to use a joomla extension

[Tompt]

It's a good idea but I would suggest that you really want that as part of your main domain rather than a subdomain. Any links pointing at it wouldn't be helping the main domain.

Now I don't know enough to suggest a fix, but a quick google found me this:

http://www.google.com/support/forum/p/Webmasters/thread?tid=5e5e79427977d86a&hl=en

I've never used mod_proxy, but apparently you can use it to have a different ip address for a subfolder. I believe it's ProxyPass Directive that you're after.

Hope that helps.