I've just come accross a secondary mirrored domain for the site of company I am working for, and just need confirmation that this potentially is having a negative impact on SEO before I tackle the guys who built the site. For a while now, I've been puzzled why the site isn't performing as well as it should in google searches (given regular updates, quantity of quality backlinks, age of domain, niche nature of product etc), and I suspect this mirror might be playing a big detrimental effect, understanding that google penalises duplicate content. In this case, example.com is mirrored by example-supplies.com, both sites look identical, and as soon as any update is made on the primary site example.com, the secondary example-supplies.com automatically mirrors this. When I search site:example-supplies.com in google, it appears as separate entity, and seems to have acquired it's own page ranking. Does anyone have any thoughts why the site builders might have done this? The system they're using is .aspx , which I am unfamiliar with so maybe I've missed something. Am I right in thinking google doesn't look down kindly on mirrors of this nature? And that the split effect of these two domains is waste of link juice etc? Finally, if as I suspect this might be costing us in terms of SEO, I will have to look into 301 redirecting the secondary domain so that only the primary domain generates traffic, any advice here? Would that mean losing the PR/places in search already gained by the secondary domain? Redirecting the homepage should be straight forward enough, but would it ever be possible to do a whole scale redirect so that example-supplies.com/productcategory-productname.aspx is redierected to the relevant page on the primary domain? Help appreciated
it could happened by error, sometimes it is used for dev environment and by mistake it get published with a single link somewhere. you can do the 301 redirects, that is best for SEO.
Not sure if you are global or not, but could've they geo-positioned the 2nd domain for a different latitude and longitude?