I had a client recently ask me about a blog that was using TypePad’s domain mapping feature and it was causing duplicate homepage URLs for the blog. The first was to http://blog.clientsite.com and the second was to http://blog.clientsite.com/blog/. They were concerted that their Technorati rank and linking efforts were being compromised. And, of course, they wanted a fix.
I did some digging around it and it turns out that it’s the way the domain mapping was setup in TypePad that was causing the issue. It can be fixed, but there are consequences.
In the client’s TypePad account there are actually two blogs, each with a unique URL.
Out of the two blogs above, #1 is set up as the ‘home blog’ meaning that it can be accessed via the main URL (http://blog.clientsite.com/) and the unique URL (http://blog.clientsite.com/blog/).
When the domain mapping was setup, the entire account was mapped to blog.clientsite.com, thus the home and unique blog URLs were included.
If just #1 was mapped to blog.clientsite.com, then no /blog/ folder would have show up.
However, fixing the domain mapping wasn’t going to be easy. The first option was to change domain mapping settings. This would result in all blog URLs changing and the old URLs becoming invalid. The only way to fix the duplicate URL issue, and not break any existing URLs, would be to move the blog to a different sub domain, like weblog.clientsite.com, then setup blog.clientsite.com as a valid hosting account and create 301 redirects for all old URLs to the new URLs. The downside here is that Google may temporarily penalize the new sub domain as it doesn’t have any history.
The issue with duplicate homepages are all in how TypePad’s domain mapping is set up. I really wish TypePad would just 301 redirect the home blog URL to the unique blog URL or vice versa. However, that’s not an option that I saw.
The client decided to just leave things as they are for now. They are planning on moving away from TypePad so any work now would just be short-term. Later this year, we’ll probably move them to a local WordPress install and ensure that there is only one blog URL.
If you have TypePad, and are considering using domain mapping, ensure that you just map the specific blog to your site to avoid duplicate homepages. Granted, if you want to map multiple blogs or other TypePad features to one sub domain, than you can’t avoid the issue and will have to map the whole TypePad account.