I've set up a domain mapping multisite successfully with sub-domain install. I originally thought that a subdomain install would be more seo friendly to the main network site because a sub-dir install would basically show duplicate content (on networksite.com/sub and on sub.com). In retrospect i guess a sub domain would also show duplicate, but it doesn’t ...it seems with domain mapping (as i have it with sub domains) its going to sub.networksite.com and will redirect to networksite.com and says 'open registration is not allowed'.
Im wondering if it will act the same with sub dir install, and otherwise how can i hide the contents of the sub dir? (htaccess noindex or something?) This seems like a better way to go because my host (dreamhost shared) doesn’t allow wildcard DNS.
Of course its all virtual so is there actually any difference with a sub-domain vs sub-dir install??
Furthermore, ive read so far its hard to change from sub-domain to sub-dir, any quick tips on that appreciated!
also, does anyone have any thoughts on what or where there might be duplicate content?? this whole domain mapping thing seems strange and im worried about repercussions or penalties from google.