Is there any SEO disadvantage in using a subdomain to host a blog on Wordpress or Blogger? I don't want to go to the trouble of creating a blog module for my site - I'd rather just set up a CNAME entry and point a subdomain to a free Wordpress or Blogger account. Will Google punish me for doing this by claiming that I have "duplicate content" - i.e. the intro text for each blog entry will be on my main site and the full details will be visible on Wordpress/Blogger? Is it better to incorporate the blog functionality into my main site? Are there any other potential disadvantages to this subdomain/external hosting approach using a free blog host?
There are a lot of advantages to self-hosting your blog.
- You can do whatever you want with your own self-hosted blog. On Wordpress you could get banned and lose all of your content.
- You can host ads or and do other commercial stuff not possible on Wordpress. (The free wordpress blog doesn't allow any advertisements other than their own ads).
- Better ranking opportunity in search engines by using your own top-level domain.
- You can modify your functionality at will.
- It looks more professional and gives you bragging rights.
- On Wordpress you may run up against bandwidth restrictions if your blog gets really popular - you won't be able to do anything about it.
Willem Obst answer makes some excellent points, but two serious accusations that are not correct. I know these are incorrect because I am part of the WordPress.com team.
Num 1. If there is a ToS issue, we work with our customers to resolve the issue. In the rare case, where a blog is suspended, the customer is still assisted with exporting their content.
Num 6.We have no bandwidth limits and never have.
Many companies use free WordPress.com for their blog. Here are some examples http://wordpress.org/showcase/flavor/wordpresscom/
WordPress.com is also is a blogging community which gives you access to a large audience and the community features like the global tag pages.
It's a great way to get a blog going, and there is no lock in. Here is an example of a blog by some friends that started on WordPress.com and since moved to host it themselves to gain the additional flexibility Willem describes so well: http://blog.bootuplabs.com/
Finally to the original question. It's a mixed bag.
The nay sayers to using a subdomain will focus on Google and other search engines generally treating the subdomain as it's own domain with it's own authority.
The pro subdomainers will focus on it being another opportunity for a result in Google and the search engines. As is the case for the "bootup labs" example. (Although, Google's Matt Cutts over a year ago promised this was changing.)
Unrelated to SEO, many teams use a subdomain or separate domain all together for web security reasons. You may notice that http://blog.flickr.net/ is on flickr.net instead of flickr.com primarily -- I understand -- for this reason.
In answer to the question.... NO.
The question you asked is also a little ambiguous. Are you wanting to host your own blog ie run it on your own server under a subdomain, or are you wanting to add a CNAME entry that links to your blog.
There are benefits to both:
Running your own - Advantages:
- You can control every aspect of it
- You can change the design/layout as much as your coding ability can handle
- If you have a fast server, your blog will be served to viewers extremely well
- You can advertise on your own blog - Google Adwords/Adsense etc...
- You can setup advanced analysis of traffic and see every little detail about everyone who visits your blog
- You can tweak the SEO of your blog to the 'n'th degree
Running your own - Disdvantages:
- Hosting a blog (especially a popular one) requires a pretty powerful web server
- You have to maintain the blog and security of the blog eg. users and permissions
- Dedicated Server hosting can be expensive
- Hosting blogs use a lot of bandwidth
Using a third party blog - Advantages:
- Generally free
- No strain on your server/bandwidth
- Security and permissions management is limited but managed by the host
- Generally hosted blogs have an extremely user-friendly GUI
Using a third party blog - Disvantages:
- Sometimes include advertising that benefits the host not your company/blog
- Very limited ability to customise/edit the design of the blog
- Limited control over the security and user management
- Other hosts can choose to stop offering a blog hosting service
In regards to SEO and blogs:
Your blog is not going to suffer or be penalised by GOogle/Yahoo/Other search engines if you use a CNAME redirection to another host.
You will not get penalised by a search engine for duplicate content if the content is not completely duplicated on, for example if your main domain uses the title and summary of what is on your blog hosted on the subdomain.
If you adhere to the main SEO principles there is no reason why your blog would suffer on a subdomain:
- Using relevant addressing methods eg. yourblog.yourdomain.com/title-of-blog-article.html
- Use W3C compliant/correct XHTML/HTML/CSS code
- Use appropriate and relevant META data (keywords, descriptions, titles) for the blog and the articles.
- Relative linking instead of absolute linking
Hope this helped. If you have any other questions feel free to ask