I have a website and its domain has been used for several years. Now I want to use an additional new name for the site, so I got a new domain. There are four valid addresses now:
http://www.new.com, and they all show the same site; they are synonyms (no re-direction).
I am using Google Webmaster Service. So far my sitemap contained lines for
http://www.old.com (and I always wondered whether I should have
http://old.com in there, too, thus listing each page twice). <- This would be my first question: should I or not? Would it be good or bad or wouldn't it matter at all?
Now the same site can also be called via
http://www.new.com. What to do now? Add this as a new website in Google Webmaster Service? This seems ridiculous, as it is the same site (with another name). And I would even fear that Google might feel betrayed and punish my site with a low rank for the duplicate post.
However, the new addresses do exist. So where to tell Google that this is the case? How to make Google know that
And: How to write the sitemap that I submit to Google? Shall it contain one domain only or both? The Website is registered with Google as
www.old.com. Would I even be allowed to have
www.new.com in the same sitemap? Would it do good or bad?
I already read on https://support.google.com/webmasters, but didn't find answers to my (rather basic?) questions. I don't use Google Analytics.